mesoarchaean to lower jurassic u-pb and sm-nd ages...

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Geological Survey of Finland, Special Paper 48Mesoarchaean to Lower Jurassic U-Pb and Sm-Nd ages from NW Mozambique

GTK Consortium Geological Surveys in Mozambique 2002–2007,edited by Yrjö Pekkala, Tapio Lehto & Hannu MäkitieGeological Survey of Finland, Special Paper 48, 81–119, 2008

MESOARCHAEAN TO LOWER JURASSIC U-Pb AND Sm-Nd AGES FROM NW MOZAMBIQUE

byIrmeli Mänttäri

Mänttäri, I. 2008. Mesoarchaean to Lower Jurassic U-Pb and Sm-Nd ages from NW Mozambique. Geological Survey of Finland, Special Paper 48, 81–119, five figures, two tables and three appendices.

This paper exclusively presents isotopic ages for 35 rock samples from NW Mozam-bique sampled during the geological mapping of the LOT2 area. Dating methods in-clude SHRIMP and TIMS zircon U-Pb dating and the mafic rocks were dated using Sm-Nd mineral isochrones. The age range of felsic to mafic magmatic rocks varies from 2.91 Ga to 0.18 Ga. Several samples have ~500 Ma low Th/U zircon phases evi-dencing Pan-African metamorphism. Additional thermal event at ~0.8 Ga is indicated by anomalously high lower intercept ages. An indication of the existence of a ~3.1 Ga protolith was found from two samples.

The oldest dated rock sampled from the eastern extension of the Archaean Zim-babwe craton to Mozambique is a tonalite with a zircon U-Pb age of 2907 ± 16 Ma. Four apparently Archaean ages of 2.71–2.50 Ga were dated from other TTG gneisses located in southern to northern parts of the Archaean domain. Additionally, these show Pan-African metamorphism at 520 ± 16 Ma. A ~1.8 Ga dolerite intrudes the Manica greenstones. Within the Archaean domain, Palaeoproterozoic Gairezi Group garnet gneiss cut by a ~1.0 Ga dolerite and Rushinga Group garnet-sillimanite gneiss indicate a maximum sedimentation age of ~2.0 Ga and supplementary Archaean provenanc-es. These sedimentary units suffered metamorphism at 518 ± 6 Ma. The tectonically emplaced Mesoproterozoic Báruè Complex in the core of the southern LOT2 area encloses ~1.1 (-1.3) Ga felsic igneous rocks with ~520 Ma metamorphic monazite. Crystalline rocks in the northern part of the LOT2 area covering the northern part of the Tete Province mainly have Mesoproterozoic ages. A felsic/intermediate volcanic rock from Fíngoè Supergroup yields a zircon U-Pb age of 1327 ± 16 Ma and all the dated granitic rocks are younger than this with ages between 1.2 Ga and 1.04 Ga. A gabbro from the Chipera Massif equivalent to the Tete Suite was dated at 1047 ± 29 Ma (ЄNd of +1.4). The few dated detrital zircon cores from Zámbuè Supergroup metas-andstone indicate a 1.3–1.2 Ga maximum sedimentation age and additional 2.7 Ga, 2.52 Ga, and 2.1 Ga sedimentary provinces. Late Mesoproterozoic Grenville ages were also dated from the Chacocoma granite (~1.05 Ga) located S of the coeval Tete Suite mafic plutonic rocks and from the Mashonaland dolerite (1.1 Ga; ЄNd= -7.3) intruding Umkondo metasediments further to the south from the LOT2 area. Neoproterozoic rocks comprise the ~0.86 Ga aplite granites belonging to Guro Bimodal Igneous Suite close to the northern part of the Archaean terrain. Moreover, Atchiza Suite gabbro, NW of the lake Cahora Bassa and the Matunda Suite gneiss located west of the Atchiza gabbro have ages of ~ 0.86–0.80 Ga. Pan-African metamorphism is evidenced by low Th/U metamorphic zircon domains. Palaeozoic Suites include the ~0.5 Ga Pan-African felsic rocks intruding the Mesoproterozoic rocks of the northern parts of the Tete prov-ince. Mesozoic Jurassic ~180 Ma Karoo event magmatism is evidenced by a syenite from the Gorongosa Intrusive Suite intruding the Mesoproterozoic Báruè Complex, Rukore Suite granite next to Zimbabwe border, and the Moeza dyke north of Tete.

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Geological Survey of Finland, Special Paper 48Irmeli Mänttäri

Key words (GeoRef Thesaurus, AGI): igneous rocks, gneisses, absolute age, U/Pb, Sm/Nd, Archean, Proterozoic, Paleozoic, Mesozoic, Zimbabwe Craton, Mozambique.

GTK - Geological Survey of Finland, P.O.Box 96, FIN-02151 Espoo, Finland

E-mail: [email protected]

The “Mineral Resource Management Capacity Building Project, Republic of Mozambique, Compo-nent 2: Geological Infrastructure Development Pro-gramme, Geological Mapping LOT 2, 2002–2006” produced updated geological maps at the scale 1: 250 000 with explanations, covering the Provinces of Tete, Manica, and Sofala in NW Mozambique. During the bedrock mapping of the LOT 2 area, 37 rock samples were collected for radiometric dat-ing (Table 1) by geologists of a consortium lead by GTK (Geological Survey of Finland). The zir-con TIMS U-Pb and Nd-Sm mineral isochron ages were processed at GTK and the secondary ion mi-croprobe (SHRIMP) zircon U-Pb isotopic data were measured at VSEGEI, St. Petersburg.

For SHRIMP dating, only a limited number of analyses were performed. Therefore, especially in the case of sedimentary rocks, the age results may only be considered as preliminary. Therefore, further U-Pb analyses would be needed for comprehensive understanding of sedimentary provinces and the

INTRODUCTION

maximum sedimentation ages. In general, the zir-con in many Archaean rock samples was strongly altered and therefore TIMS dating yielded highly discordant U-Pb isotopic data. In addition, the very strong effect of the Pan-African metamorphism at ~0.5 Ga and sometimes the Early Pan-African proc-esses at ~0.8 Ga either disturbed the zircon U-Pb system, preferably in metamict grains, or crystal-lized a new zircon phase.

This paper exclusively presents the radiometric age results for 35 rock samples from the LOT 2 area, NW Mozambique. Further geological connec-tions and sample information must be obtained from the original map explanations (GTK Consortium, 2006a-d), from the other papers in this volume (e.g. Koistinen et al. 2008, Mäkitie et al. 2008, West-erhof et al. 2008), and from previous publications (Hunting team 1984, Koistinen et al. 2006, Mäkitie et al. 2006, Mänttäri et al. 2006, Westerhof 2006, and references therein).

ANALYTICAL METHODS

For ID-TIMS U-Pb dating, heavy minerals were separated using heavy liquids (methylenediiodide and Clerici’s solution) and a Frantz magnetic sepa-rator. The final selection of the minerals for U-Pb analysis was carried out by hand picking. The de-composition of selected zircon and monazite and extraction of U and Pb for multigrain ID-TIMS isotopic age determinations mainly followed the procedure described by Krogh (1973, 1982). 235U-208Pb (zircon) and 235U-206Pb (monazite) spiked and unspiked isotopic ratios were measured using a VG Sector 54 thermal ionization multicollector mass spectrometer (TIMS) in the static mode. According to repeated measurements of Pb standard SRM981,

TIMS U-Pb

the measured isotope ratios were corrected for 0.12–0.10 ± 0.05% / a.m.u. mass discrimination. Pb/U ratios were calculated using the PbDAT pro-gram (Ludwig, 1993). Plotting of the U-Pb isotopic data and age calculations were performed using the ISOPLOT/EX 3.00 program (Ludwig 2003). Com-mon lead corrections were carried out using the age-related Stacey’s and Kramers’s (1975) lead isotope compositions (206Pb/204Pb ± 0.2, 208Pb/204Pb ± 0.2, and 207Pb/204Pb ± 0.1). The total procedural blank level was 20–50 pg. All the ages were calculated with 2σ errors and without decay constant errors. In the figures, the data-point error ellipses are at the 2σ level.

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Selected zircon grains were mounted in epoxy resin together with chips of the TEMORA (Mid-dledale Gabbroic Diorite, New South Wales, Aus-tralia) and 91500 (Geostandard zircon; Wieden-beck et al. 1995) reference zircons. The grains were sectioned approximately in half and polished. Back-scattered electron images (BSE) and cathodo luminescence (CL) images were prepared for all zircons. The zircon U-Pb analyses were performed using a SHRIMP-II ion microprobe at Center of Isotopic Research, VSEGEI, St.Petersburg, Russia. Each analysis consisted of 5 scans through the mass range. The spot diameter was ~20 μm, and primary beam current was ~4 nA. The raw data reduction using the SQUID Excel Macro of Ludwig (2000) was done in a similar manner to that described by Williams (1998, and references therein). The Pb/U ratios were normalized relative to a value of 0.0668 for the 206Pb/238U ratio of the TEMORA reference

SHRIMP U-Pb dating

zircon, equivalent to an age of 416.75 Ma (Black et al. 2003). The common lead correction was car-ried out using the measured 204Pb and modern lead isotope composition (Stacey and Kramers 1975). Uncertainties given for individual analyses (App.1) are at the one σ level. The concordia plots and age calculations were performed using ISOPLOT/EX 3 (Ludwig 2003). In a few cases, the concordia ages were calculated using SQUID (Ludwig 2000). All the results are calculated at the 2σ level with the ig-nored decay constant errors. The uncertainties of the means of the Pb/U standard calibrations (see App. 1) are not included in table errors but are included in final concordia age errors: either added to the age calculated by Isoplot, or when calculated using SQUID, they are automatically taken into account in the final ages. In figures, the data-point error el-lipses as well as the error bars are at the 2σ level.

Sm-Nd mineral dating

For Sm-Nd analyses, handpicked mineral concen-trates were washed ultrasonically in warm 6 N HCl for 30 min, and rinsed several times in ultra clean water. The samples (150–200 mg) were dissolved in HF-HNO3 using Savillex® screw cap teflon beakers for 48h. A mixed 149Sm-150Nd spike was added to the sample prior to dissolution. After evaporation of flu-orides the residue was dissolved in 6N HCl. Sm and Nd were separated in two stages using a conventional cation-exchange procedure (7 ml of AG50Wx8 ion exchange resin in a bed of 12 cm length) and a modi-fied version of the Teflon-HDEHP (hydrogen di-ethylhexyl phosphate) method developed by Richard et al. (1976). The measurements were performed in a dynamic mode on a VG SECTOR 54 mass-spec-trometer using Ta-Re triple filaments. The 143Nd/144Nd ratio is normalized to 146Nd/144Nd = 0.7219. The aver-

age value for the La Jolla standard was 143Nd/144Nd = 0.511850 ± 10 (std, 50 measurements since 2002). The Sm/Nd ratio of the spike was calibrated against the Caltech-mixed Sm/Nd standard (Wasserburg et al. 1981). Based on duplicated analyses the er-ror in 147Sm/144Nd was estimated to be 0.4%. Initial 143Nd/144Nd and ε were calculated with the follow-ing parameters: λ147Sm = 6.54x10-12a-1, 147Sm/144Nd = 0.1966 and 143Nd/144Nd = 0.51264 for present CHUR (Jacobsen and Wasserburg 1980). T-DM was calcu-lated according to DePaolo (1981). Measurement on the rock standard BCR-1 provided the following val-ues: Sm = 6.58 ppm, Nd = 28.8 ppm, 147Sm/144Nd = 0.1380, 143Nd/144Nd = 0.51264 ± 0.00002. The blank measured during the analyses was 30–100 pg for Sm and 100–300 pg for Nd. Programs by Ludwig (2003) were used for age calculations.

AGE RESULTS

General information

The sample locations of the 35 dated rock sam-ples are presented in Figure 1. The rock types, cor-responding Suite and Group names, and related coordinates are collected in Table 1. The analyti-cal data are presented in three appendices, namely Appendix 1, Appendix 2, and Appendix 3 for U-Pb SHRIMP, U-Pb TIMS, and Sm-Nd TIMS isotopic

data, respectively. Some selected zircon CL images as well as the U-Pb concordia diagrams and Sm-Nd plots are collected in Figures 2 and 3, 4, respective-ly. For further geological information, please refer to the original map explanations (GTK Consortium 2006a–d).

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Fig. 1. Simplified geological map of the LOT 2 area, NW Mozambique (simplified and modified after the work by the GTK Consortium). Sample numbers and sites of the dated rock samples are marked on map. See Table 1 for further sample information.

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Table 1. Sample information and dating methods.

Zircon separated from Rio Capoche granite is either short to long prismatic with clear crystal faces or the grains are ellipsoidal to quite tabular with smooth crystal faces. Within these transparent and reddish crystals, there are also translucent and more brownish grains. In all, although the shape of the crystals may vary, the population looks quite homogeneous. In CL images (Fig. 2), many grains show CL-paler zoned core domains surrounded by

Mos-1 / 1055-02 Rio Capoche Granite gneiss

CL-darker zones. However, as the magmatic zon-ing continues similarly through the whole crystal these do not show structurally separate core and rim domains. There are also longer zoned zircon grains without CL-pale centre domains and a few are completely CL-black.

A total of 18 zircon domains were dated using SHRIMP (App. 1). Seven of the analyses were rejected due to high common lead proportions.

LAB ID

FIELDNUMBER EASTING NORTHING ROCK-TYPE SUITE/GROUP DATING METHOD

Mos-1 1055-02 468284 8326745 Granite gneiss Rio Capoche granite U/Pb on Zr, SHRIMPMos-2 2253-03 432370 8416395 Monte Dombe granite Cassacatiza Suite U/Pb on Zr, TIMSMos-3 1024-02 527931 8134434 Aplite granite Guro Bimodal Suite U/Pb on Zr, SHRIMPMos-4 1072-02 494386 8126625 Aplite granite Guro Bimodal Suite U/Pb on Zr, TIMSMos-5 1097-03 541966 8202648 Granite Chacocoma granite U/Pb on Zr, SHRIMPMos-6 1170-03 513559 8099375 Massanga gneiss Mudzi Metamorphic Complex U/Pb on Zr, TIMSMos-7 1284-03 5037824 8119250 Gneiss Mudzi Metamorphic Complex U/Pb on Zr, SHRIMPMos-8 2450-03 463512 8369001 Granite Macanga Granite U/Pb on Zr, SHRIMPMos-9 2007-03 431180 8414421 Granite Cassacatiza Suite U/Pb on Zr, TIMSMos-10 2001-02 376147 8323791 Granite Monte Sanja Suite U/Pb on Zr, TIMSMos-11 2297-03 571952 8338810 Desaranhama granite Furancungo Suite U/Pb on Zr,TIMSMos-12 4493-03 316890 8371137 Granite Sinda Suite U/Pb on Zr, SHRIMPMos-13 6034-03 489885 8326199 Granite Castanho Granite U/Pb on Zr,TIMSMos-14 2395-03 279324 8287732 Gabbro Atchiza Suite Sm/Nd mineral isochronMos-15 4241-03 365684 8364734 Granite Cassacatiza Suite U/Pb on Zr, SHRIMPMos-16 13016-03 247659 8287248 Granite gneiss Matunda Suite U/Pb on Zr, SHRIMPMos-17 13014-03 433666 8286298 Gabbro Chipera Massif Sm/Nd mineral isochronMos-18 13032-03 384685 8304453 Granite Monte Capirimpica granite U/Pb on Zr, TIMSMos-19 2638-04 497125 8124948 Aplite granite Guro Bimodal Suite U/Pb on Zr, SHRIMPMos-20 2943-04 491312 8124697 Garnet-sillimanite

gneissRushinga Group U/Pb on Zr, SHRIMP

Mos-21 1519-04 527153 8040960 Fudeze orthogneiss Mudzi Metamorphic Complex U/Pb on Zr, SHRIMPMos-22 2893-04 472183 8158374 Granite Rukore Suite U/Pb on Zr,TIMSMos-23 13625-04 491095 7904308 Tonalite Mavonde Complex U/Pb on Zr, SHRIMPMos-24 15273-04 624078 7964477 Syenite Gorongosa Intrusive Suite U/Pb on Zr, TIMSMos-25 25416-04 481495 7908114 Dolerite Archaean terrain Sm/Nd mineral isochronMos-26 1011-02 512044 8008145 Garnet gneiss Gairezi Group U/Pb on Zr, SHRIMPMos-27 14410-03 503380 8325794 Moeza Dike Rukore Suite Sm/Nd mineral isochronMos-28 19313-04 594472 7857362 Granite Báruè Complex U/Pb on Zr, SHRIMPMos-29 19290-04 599246 7875441 Inchapa granodiorite Báruè Complex U/Pb on Mon and Zr, TIMS

and SHRIMPMos-30 19140-04 509199 7898986 Messeca granodiorite Mavonde Complex U/Pb on Zr, TIMSMos-31 6845-04 547097 7882708 Monte Chissui tonalite Báruè Complex U/Pb on Zr, TIMSMos-32 13888-04 491576 7758265 Dolerite Mashonaland dolerite (post-

Umkondo)Sm/Nd mineral isochron

Mos-33 4158-03 365692 8363637 Metasandstone Zámbuè Supergroup U/Pb on Zr, SHRIMPMos-34 3157-03 376146 8323802 Felsic/intermediate

metavolcanic rockFíngoè Supregroup U/Pb on Zr, SHRIMP

Mos-37 1714-05 515362 7896822 Dolerite Post-Gairezi Sm/Nd mineral isochronZr=zircon; Mon=monazite

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Fig 2

Fig. 2. Selected CL images for SHRIMP U-Pb dated samples. The analysis spot sites and corresponding analysis numbers are indicated (see Table 3). Mos-1 granite gneiss: 2.1 and 3.1 belong to the 1.20 Ga age group; 4.1 has a high common lead content, and 15.1 shows post-crystallization lead loss. MOS-3 aplite granite: Magmatic ~850 Ma zircon. MOS-5 granite: Magmatic ~1.05 Ga zircon (3.1 and 5.1) and a supposedly inherited zircon with a CL-dark, disturbed core and a CL-bright metamorphic rim with a metamorphic age of ~1.05 Ga. Mos-7 gneiss: 6.1 and 9.1 are ~2.7 Ga magmatic zircon; younger and possibly metamorphic CL-dark zircon domains (7.1 and 13.1); CL-pale, low Th/U metamorphic rim 5.1 is ~520 Ma. Mos-8 granite: CL-dark ~470 Ma zircon with visible zoning (1.1 and 2.1); zircon showing a blurry internal structure (no analysis). Mos-12 granite: Zoned and homogeneous ~500 Ma zircon domains. Mos-15 granite: All analysed zircon domains are ~1.1 Ga. Mos-16 granite gneiss: ~800 Ma ages from 8.1, 6.1, 1.2, and 4.2; ~500 Ma from low Th/U domains 5.1, 6.2, 4.1, and 1.1; rounded, completely metamict zircon 4 enclosing a ~750 Ma zoned zircon (recrystallized?). Mos-19 aplite granite: Magmatic 850 Ma zircons (4, 5, and 6); metamorphic 850 Ma ages from rounded metamict zircon (3.2), its CL-pale rim (3.1), and from the CL-dark rim domain of zircon 9, which has a ~500 Ma core. Mos-20 garnet-sillimanite

Mos-3

14.1

4.1

12.1

Mos-1

2.1

15.1

4.1

3.1

6.16.2

3.1

5.1

6.1

Mos-5

Mos-7

13.1

7.1

6.1

9.1

5.1

1.1

Mos-8

2.1

2.22.1

10.2

10.1

1.1

Mos-15

2.1

5.1

3.1

3.2

Mos-16

Mos-121.1

1.2

5.1

4.1

6.1

6.2

8.1

4.2

Mos-19

3.1

3.2

6.1

5.1

4.1

9.1

9.2

9.1

9.21.1

1.2

3.1

12.1

Mos-21

1.1

1.2

2.13.1

12.1

3.1

Mos-23

4.1

5.11.1

Mos-20

Mos-26

12.1

9.1

10.1

15.1

Mos-28

11.1

8.1

12.1

13.1

5.2

5.1

6.1

7.1

Mos-29

10.1

6.1

6.2

8.1

8.2

9.1

3.1

2.1

5.1

Mos-33

1.1

11.1

2.1

Mos-34

100 m

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gneiss: 2.8 Ga zoned zircon (1.2) enveloped by a CL-bright, low Th/U ~500 Ma rim (1.1); zircon core 9.2 plotting on a 1.98 Ga reference line is surrounded by a ~500 Ma CL-dark, low Th/U zircon phase (9.1); zoned core 12.1 plots on the ~2.5 Ga reference line and 3.1 is a ~500 Ma phase. Mos-21 orthogneiss: A > 3 Ga core (1.1) and ~2.60 Ga magmatic zircon phases (1.2, 2.1, and 3.1). Mos-23 tonalite: ~2.9 Ga magmatic zircon grains (1.1, 4.1, and 5.1). Mos-26 garnet gneiss: ~3.1 Ga rounded zircon (9.1); 15.1 is ~2.7 Ga; 10.1 and 12.1 plot on a 2.04 Ga cluster. Mos-28 granite: Zircon 8 is magmatic zircon in the 1119 ± 21 Ma zircon group and 13 and 12 are examples of inherited grains. MOS-29 granodiorite: 5.1, 6.1, and 7.1 magmatic ~1.08 Ga zircon domains; analysis from the CL-dark, low Th/U rim is highly discordant, indicating metamorphism at ~500 Ma. MOS-33 metasandstone: The youngest zoned zircon domain is ~0.83 Ga (2.1); detrital cores give ages of 2.7 Ga (6.2), 2.1 Ga (8.2), and 1.3-1.2 Ga (3.1, 10.1); CL-dark metamorphic rim zircon phases are 1.2 Ga (5.1) and 0.4 Ga (8.1) (analysis 6.1 was rejected due to a high common lead proportion). MOS-34 felsic/intermediate metavolcanic rock: Typical magmatic 1.3 Ga zircon (1.1 and 2.1); younger zircon domain 11.1 must have suffered lead loss.

On the concordia diagram (Fig. 3A), five analyses from zoned zircon domains plot in a cluster yielding a concordia age of 1201 ± 10 Ma. The remaining six concordant analyses plot roughly between 1050 Ma

Mos-2 / 2253-03 Monte Dombe granite, Cassacatiza Suite

Mos-3 / 1024-02 aplogranite gneiss, Guro Suite

and 1150 Ma. The younger data analysed mostly on CL-dark zoned domains probably show minor lead loss and therefore 1201 ± 10 Ma is interpreted as the age for the Rio Capoche granite.

Monte Dombe granite has a rather heterogene-ous zircon population. Zircon can be transparent to translucent, brownish to yellowish and short pris-matic or colourless and tabular with pyramidal edg-es, and the turbid, brownish grains exhibit mostly larger grain sizes.

Four zircon fractions were analysed for their Pb/U ratios using TIMS (App. 2). In general, the 206Pb/204Pb ratios are low and the analyses show a

high degree of discordance. As is normal, the most abraded fraction shows the lowest U content and the highest 206Pb/204Pb ratio. The analysed fractions plot roughly on the same line intercepting the concordia curve at 1102 ± 24 Ma (Fig. 3B). However, as the zircon population of the Monte Dombe granite is fairly heterogeneous and the analyses very discord-ant, it is difficult to judge the factual meaning of the 1102 ± 24 Ma age.

Mos-4 / 1072-02 aplogranite gneiss, Guro Suite

Sample Mos-3 contains abundant zircon with quite a homogeneous outlook. Grains are princi-pally long prismatic (l:w ~3–4), fairly colourless to yellowish-brownish, and transparent to translucent and contain occasional inclusions. Large, turbid, dark, and more formless grains are in the minority. In CL images (Fig. 3), the zircon shows clear mag-matic zoning and only a few show a dark, spotty CL indicating metamictization. A few probable cores were identified and some grains show thin later zir-con growth.

Fifteen zircon spots were dated using SHRIMP II (Appendix 1). As the supposed metamorphic rims were too thin for dating, all the age data come from magmatic domains only. On the concordia diagram (Fig. 4C), the concordant to nearly concordant data scatter between 760 and 920 Ma. The upper inter-cept age and the weighted average of the 207Pb/206Pb ages are equivalent. Thus, the age of the aplogranite gneiss is 852 ± 15 Ma. Later, most probably Pan-African metamorphism is evidenced by the thin zir-con envelopes around the magmatic crystals.

Aplogranite gneiss Mos-4 yielded a large amount of zircon with varying grain-size. It is predominant-ly almost colourless, transparent, and euhedral to subhedral (l:w = 3–5), and frequently contains dark inclusions. In the < 75 μm grain-size fraction, the grains have smooth surfaces. In the coarser grain-size fraction, dark brown and formless, most proba-bly inherited zircon grains also occur. For U-Pb dat-ing only the bright euhedral crystals were selected.

Four zircon fractions were analysed for their Pb/

U ratios using TIMS (App. 2). The zircon fractions have moderate U concentrations and the abraded fractions show the lowest U contents and the high-est 206Pb/204Pb ratios within a grain-size group. In general, the 206Pb/204Pb ratios are high and especially the abraded analyses show only minor discordance. The four analysed zircon fractions plot well on the same discordia line with concordia intercept ages of 867 ± 9 Ma and 389 ± 61 Ma (MSWD = 1; n = 4) (Fig. 3D).

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Mos-5 / 1097-03 Chacocoma granite

Mos-6 / 1170-03 Massanga gneiss, Mudzi Metamorphic Complex

The amount of zircon in Chacocoma granite is large, the population is morphologically homoge-neous, and its grain-size varies. Zircon is euhedral, long (l:w ~4–5), transparent to translucent, and col-ourless to brownish. Among these, elongated and more tabular grains, as well as grains with poorly de-veloped crystal faces were detected. In CL (Fig. 2), the zircon is commonly dark, shows magmatic zon-ing, and is occasionally enveloped by thin, or rarely wider, metamorphic CL-bright, structurally homo-geneous rims. These, in turn, can be corroded and replaced or enveloped by a still later and thinner zircon phase. In a few grains, metamorphic or mag-matic CL-medium dark rims occur between the CL-bright rims and core domains. Furthermore, some zircon grains or zircon domains show disturbed magmatic zoning to more blurry structures indicat-ing the beginning of metamictization.

A total of 15 zircon domains were dated using SHRIMP II (App. 1). Nine of these represent mag-

matically zoned crystals with or without thin meta-morphic rims. In addition, two CL-bright and one CL-medium dark rim domains were wide enough for dating. The CL-dark, mostly zoned core do-mains of the grains with wide rim domains were also dated.

On the concordia diagram (Fig. 3E), the rather concordant age data scatter primarily between 960 and 1080 Ma. One zoned zircon (Mos-5.8.1) gives an apparently higher 207Pb/206Pb age of ~1.2 Ga. However, the error is large and it partly overlaps with the other data. The U-Pb data from rim and core domains in single zircon grains are coeval. Be-cause there is no way to divide the data into separate age/domain groups and the age data are scattered, the weighted average of 207Pb/206Pb ages would give an age estimate for the rock. The data with the ap-parently highest 207Pb/206Pb age are excluded from the 1046 ± 20 Ma mean age.

Mos-7 / 1284-03 gneiss, Mudzi Metamorphic Complex

The amount of zircon in supposed Arcahean Massanga gneiss is extremely low. Zircon is either euhedral elongated (l:w ~2) or round to oval, very bright, and rather colourless. The grain-size varies from medium to extremely fine-grained.

Only three zircon fractions were analysed for their Pb/U ratios (App. 2) with TIMS as the zircon amount was extremely small. In general, the 206Pb/204Pb ra-tios are high. On the concordia diagram (Fig. 3F), the three fractions give an upper intercept age of

2.63 Ga for the gneiss. Although the discordia line is practically determined only by two data points, the Archaean age is evident. This is already seen in ~2.6 Ga 207Pb/206Pb ages for the analysed zircon fractions. However, as the age data from gneiss Mos-37 from the same metamorphic complex most probably in-dicate a ~2.71 Ga magmatic age and metamorphism at ~2.5 Ga, it may be that the 2.63 Ga age estimate from Massanga gneiss is an average age.

The zircon in Mos-7 gneiss splits into two main populations. One population consists of mainly long or elongated (l:w ~4–2), euhedral, partly cor-roded (?), pale brown, translucent to turbid grains and the other of very bright, colourless, elongated to oval or round grains. Among these, other inter-mediate phases with varying grain-sizes also occur. In CL images (Fig. 2), the majority of the zircon grains show magmatic zoning, which in a few cases is disturbed with a blurry structure. Only small, of-ten disturbed/altered possible cores were found. In addition to zoned zircons, there are also rounded, internally relatively homogeneous, CL-dark, prob-

ably metamorphic grains. Many zircons are envel-oped by metamorphic CL-bright and/or darker rim phases.

A total of 15 zircon domains were dated us-ing SHRIMP (App. 1). As the zircon material was shown to be quite complex internally, the analyses were performed on zoned zircons, CL-bright rims, and CL-dark, supposedly metamorphic grains. On the concordia diagram (Fig. 3G), the U-Pb data plot partly in a cluster and most of the data are discord-ant. The age results are divided into three groups according to the dated zircon domains: 1) The zoned zircon domains form the oldest ~2.71 Ga

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Mos-3 / 1024-02 Mos-4 / 1072-02

Mos-6 / 1170-03 Mos-5 / 1097-03

Mos-8 / 2450-03 Mos-7 / 1284-03

Mos-1 / 1055-02

Dashed line ellipses:

rejected data with high

common lead

Mos-2 / 2253-03

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Mos-16 / 13016-03

rim

discordant, oldest 207 Pb/ 206 Pb age

Mos-9 / 2007-03 Mos-10 / 2001-02

Mos-13 / 6035-03 Mos-15 / 4241-03

Mos-11 / 2297-03 Mos-12 / 4493-03

Mos-18 / 13032

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Mos-21 / 1519-04 Mos-22 / 2893-4

Mos-23 / 13625-04 Mos-24 / 15273-4

Mos-26 / 1011-02

(most concordant data)

Mos-28 / 19313-04

Mos-19 / 2638-04

magmatic zircon

Mos-20 / 2943-04

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Mos-34 / 3157-03

Mos-30 / 19140-04

Mos-31 / 6845-04 Mos-33 / 4158-03

Mos-29 / 19290-04

Fig. 3. Concordia plots showing SHRIMP and TIMS zircon U-Pb isotopic data, samples from NW Mozambique. A) Mos-1/1055-02 Rio Capoche granite gneiss (SHRIMP); B) Mos-2/2253-03 Monte Dombe granite, Cassacatiza Suite (TIMS); C) Mos-3/1024-02 aplite granite, Guro Suite (SHRIMP). The inset shows the weighted average of the 207Pb/206Pb ages; D) Mos-4/1072-02 aplite granite, Guro Bimodal Suite (TIMS); E) Mos-5/1097-03 Chacocoma granite (SHRIMP). The inset shows the weighted average of the 207Pb/206Pb ages; F) Mos-6/1170-03 Maassanga gneiss, Mudzi Metamorphic Complex (TIMS); G) Mos-7/1284-03 gneiss, Mudzi Metamorphic Complex (SHRIMP); H) Mos-8/2450-03 Macanga granite (SHRIMP). The inset shows the weighted average of the 207Pb/206Pb ages I) Mos-9/2007-03 granite, Cassacatiza Suite (TIMS); J) Mos-10/2001-02 granite, Monte Sanja Suite (TIMS); K) Mos-11/2297-03 Desaranhama granite, Furancungo Suite (TIMS); L) Mos-12/4493-03 granite, Sinda Suite (SHRIMP); M) Mos-13/6035-03 granite, Castanho Granite (TIMS); N) Mos-15/4241-03 granite, Cassacatiza Suite (SHRIMP); O) Mos-16/13016-03 granite gneiss, Matunda Suite (SHRIMP). The inset shows the weighted average of the 207Pb/206Pb ages for the older group data (zoned cores, healthy magmatic crystal, and an internally quite homogeneous grain); P) Mos-18/13032 Monte Capirimpica granite (TIMS); Q) Mos-19/2638-04 aplite granite, Guro Suite (SHRIMP). The inset shows the weighted average of the 207Pb/206Pb ages for the older group magmatic zircon grains; R) Mos-20/2943-04 garnet-sillimanite gneiss, Rushinga Group (SHRIMP); S) Mos-21/1519-04 Fudeze orthogneiss, Mudzi Metamorphic Complex (SHRIMP); T) Mos-22/2893-04 granite, Rukore Suite (TIMS); U) Mos-23/13625-04 tonalite, Mavonde Complex (SHRIMP). Discordant Pb/U data from rim domains; V) Mos-24/15273-04 syenite, Gorongosa intrusive Suite (TIMS); W) Mos-26/1011-02 garnet gneiss, Gairezi Group (SHRIMP). The inset shows the weighted average of the 207Pb/206Pb ages; X) Mos-28/19313-04 granite, Báruè Complex (SHRIMP); Y) Mos-29/19290-04 In-chapa granodiorite, Báruè Complex (zircon SHRIMP and monazite TIMS); Z) Mos-30/19140-04 Messeca granodiorite, Mavonde Complex (TIMS); Å) Mos-31/6845-04 Monte Chissui tonalite, Báruè Complex (TIMS); Ä) MOS-33/4158-03 metasandstone, Zámbuè Group (SHRIMP); Ö) MOS-34/3157-03 felsic/intermediate metavolcanic rock, Fíngoè Supergroup (SHRIMP).

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age group. 2) The ~2.54 Ga upper intercept age for three rounded, internally homogeneous grains and a metamorphic rim (Mos7.7.1, 8.1, 13.1, 3.1) pre-sumably reflects metamorphism at that time. This group also includes analyses from another internal-

ly homogeneous rim (Mos7.15.1) and from a zircon domain showing disturbed zoning (Mos7.10.1). 3) The Pan-African metamorphism at 520 ± 16 Ma is indicated by two CL-bright, low Th/U rim growths (Mos7.5.1 and 11.1).

Mos-8 / 2450-03 Macanga Granite

The Macanga granite yielded abundant zircon with a fairly heterogeneous population. In addi-tion to long prismatic slim, principally translucent crystals, the large, mostly translucent to turbid, short/equidimensional, and brownish zircon grains are the most common ones. In CL images (Fig. 2), the zircon mainly shows dark CL and blurry or al-ready nonexistent zoning due to the high degree of metamictization in most of the U-rich grains. The dated spots have been selected to represent as un-disturbed zoning as possible.

A total of fifteen zircon domains were dated using SHRIMP (App. 1). One data point was reject-ed due to a high common lead content. On the con-cordia diagram (Fig. 3H), the U-Pb data are mostly concordant and scatter between 350 Ma and 650 Ma. A weighted average of the 207Pb/206Pb ages is considered to give the best age estimate for the rock. Thus, the age for the Macanga granite is 470 ± 14 Ma. However, although the dated domains re-pre-sented as undisturbed zoned domains as possib-le, they may still show lead loss and the original age of the rock could be older.

The Cassacatiza granite contains abudant zircon that is either transparent and colourless or trans-parent-translucent and yellowish. The crystals are chiefly long prismatic (l:w = 3–7), medium to coarse-grained (>200 μm), and inclusion rich.

Four zircon fractions were analysed for their Pb/U ratios using TIMS (App. 2). Zircon is quite poor in U and has uniform radiogenic 208Pb/206Pb ratios.

Mos-9 / 2007-03 granite, Cassacatiza Suite

Two fractions (A and B) with the longest air-abra-sion times show the highest 206Pb/204Pb ratios and the U-Pb results of these are concordant and equal. They give a concordia age of 1077 ± 2 Ma (Fig. 3I). The fraction C shows the most discordant age result with the lowest 206Pb/204Pb ratio. The fourth, non-abraded fraction D plots just below points A and B, but the result is not equal with these.

Monte Sanja granite contains a large amount of medium- to fine-grained, transparent to translucent, colourless or yellowish zircon with short prismatic to almost needle-like morphologies. Some of the zircon grains contain dark inclusions.

Four zircon fractions were dated using TIMS

Mos-10 / 2001-02 granite, Monte Sanja Suite

(App. 2). Zircon is quite low in U, has uniform radiogenic 208Pb/206Pb ratio, and an extremely low 206Pb/204Pb ratio. The dated zircon fractions spread well along the discordia line that intercepts the concordia curve at 1050 ± 8 Ma and 81 ± 45 Ma (Fig. 3J).

Mos-11 / 2297-03 Desaranhama granite, Furancungo Suite

Desaranhama granite yielded a large amount of mainly coarse- to medium-grained, reddish, trans-lucent to turbid zircon with sharp edges and vary-ing prism lengths (l:w = 3–8). Especially the larger crystals contain inclusions.

Using TIMS, four zircon fractions were dated (Appendix 2). The zircon is quite low in U, has

uniform radiogenic 208Pb/206Pb, and low 206Pb/204Pb ratios. The longest abraded zircon fraction D with a 207Pb/206Pb age of 1037 Ma plots near to concordia curve and the other fractions are rather discordant (Fig. 3K). The upper intercept age 1041 ± 4 Ma de-termines the age for the Desaranhama granite.

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Mos-12 / 4493-03 granite, Sinda Suite

Mos-13 / 6035-03 granite, Castanho Granite

Mos-14 / 2395-03 gabbro, Atchiza Suite

Mos-15 / 4241-03 granite, Cassacatiza Suite

Sinda granite contains abundant, short to long pris-matic zircon that is either quite colourless or yellow-ish, has a moderately coarse grain-size, and is largely transparent. In addition to a prismatic morphology, flat, equidimensional, and subhedral types also oc-cur. In CL images (Fig. 2), zircon frequently shows magmatic zoning. In a few grains, the zoning is quite blurry or homogenized and some show homogeneous zircon growth cutting the initial zoned phase. In ad-dition, a few cores were detected. However, these are mostly disturbed and/or too small for reliable dating.

A total of 15 zircon domains were dated using SHRIMP (App. 1). Dated zircon domains include zoned crystals and rim growths. All the data are concordant and plot in a same cluster on a concor-dia diagram (Fig. 3L), despite the different type of the dated domains. The concordia age for most of the data is 502 ± 8 Ma (n = 14/15). Accordingly, the seemingly younger cutting zircon phase (see Fig. 2: Mos-12/10.1) must represent later phases of the same magmatic event.

The zircon content of the Castanho granite is very high. The coarser grain-size fraction (>75 μm) mainly consists of long prismatic (l:w ~3–5), pale brown and transparent zircon, while the fine-grained (<75 μm) zircon is relatively colourless, transpar-ent, and the grains are generally shorter and more oval shaped. The zircon occasionally contains small inclusions.

Four zircon fractions were analysed for their Pb/U ratios using TIMS (App. 2). The zircon is quite poor in U, has an extremely high 206Pb/204Pb ratio, and uni-form radiogenic 208Pb/206Pb ratios. On the concordia diagram (Fig. 3M), three dated zircon fractions are just concordant with 0.65% errors for the Pb/U ra-tios. The concordia age for the concordant data is 1050 ± 2 Ma (n = 3). The slightly discordant fraction D also plots together with the other data.

The mineral separation of the Atchiza gabbro yielded abundant fresh plagioclase and pyroxene. The Sm-Nd data (App. 3 and Fig. 4D) reveal a low REE level and trend almost parallel with the chon-dritic trend. The whole rock, plagioclase, and py-

roxene analyses yield an isochron with an age of 864 ± 30 Ma (MSWD = 1) (Fig. 4A). This is the crystallization age of the main magmatic minerals. The initial epsilon value is –3.0.

The major part of the zircon in Cassacatize gran-ite is long (l:w ~3.5–5) prismatic, has a varying grain size, and is covered by yellowish to brown-ish pigment. The medium-sized grains are normally translucent, the largest are turbid, and the smaller ones quite bright. Among the long crystals, there are also a small amount of short (l:w ~2) ones. The pop-ulation looks quite uniform and the zircon shows sharp crystal edges. In CL images (Fig. 2), the zir-con generally shows well preserved oscillatory zon-ing. Only a few grains demonstrate blurry zoning and the start of homogenisation of the internal struc-tures. Many have a thin, CL-brighter rim around the

zoned zircon domains.A total of 14 zircon domains were dated using

SHRIMP (Appendix 1). The age data mostly comes from the zoned, magmatic domains and only few supposed rim and core phases were suitable for dat-ing. On the concordia diagram (Fig. 3N), the entire data plot in a cluster and 10 of the 14 spots define a concordia age of 1117 ± 12 Ma. Two of the rejected analyses have higher common lead contents, one is discordant, and the fourth one has an anomalously high U concentration. The quite homogeneous age data indicate zircon crystallization at 1117 ± 12 Ma.

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Fig. 4. Sm-Nd data. A) Mos-14/2395-03 gabbro, Atchiza Suite and Mos-17/13014-03 gabbro, Chipera Massif; B) Mos-25/25416-04 dolerite, Archaean domain and Mos-27/14410-03 Moeza Dike, Rukore Suite; C) Mos-32/13888-04 Post-Umkondo dolerite, Mashonaland dolerite and Mos-37/1714-05 Post-Gairezi dolerite; D) Whole rock evolution lines for Mos-14/2395-03, Mos-17/13014-03, Mos-25/25416-04, Mos-27/14410-03, Mos-32/13888-04, and Mos-37/1714-05.

Mos-16 / 13016-03 granite gneiss, Matunda Suite

Matunda gneiss yielded abundant, mostly rela-tively fine-grained zircon with an apparently hetero-geneous population. The zircon is mostly prismatic (l:w ~4–2) and has clear crystal faces. Colourless, mostly transparent grains are either short prismat-ic or oval-shaped and turbid ones show anhedral forms. In CL images (Fig. 2), the zircon population looks quite heterogeneous, including at least the fol-lowing types: 1) Totally altered/metamict, CL-dark zircon with occasional thin, CL-bright rims. These are the most common ones. 2) Zircon with preserved zoning in core domains. The corroded, CL-bright core domains are enveloped by a CL-dark zircon phase. 3) A few moderately healthy looking zoned crystals without rims or replacing/enveloping zircon material.

Only 15 zircon domains were dated using SHRIMP (App. 1). One data point was rejected due to a high common lead content. On the concordia diagram (Fig. 3O), the age data divides into two separate age groups: 1) The younger group consists of ages from low Th/U rim and/or replacing zircon phases, metamict and already quite homogenized grains, and from a new tip growth. A concordia age of 528 ± 4 Ma can be calculated for the late meta-morphism. 2) The older data deviate between 700 Ma and 830 Ma and come from zoned core domains and healthy zoned crystals. The six apparently older analyses deviate on the concordia curve (Fig. 3O) and therefore no concordia age can be calculated. The weighted average of the 207Pb/206Pb ages for these zircon domains is 784 ± 36 Ma.

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Mos-17 / 13014 gabbro, Chipera Massif

Mos-18 / 13032 Monte Capirimpica granite

Mos-19 / 2638-04 aplitie granite, Guro Suite

A ~700 Ma healthy, long, and zoned zircon crys-tal (Mos16.10.1) and the core (Mos16.12.1) with the highest 207Pb/206Pb age of over 900 Ma plot outside the two main age groups. However, as the error for the >900 Ma Pb-Pb age is very high and the ~700

Ma zircon has an anomalous appearance, these de-viating analyses may be considered unimportant. The initial age of the abundant rounded, metamict grains remains unresolved as they now show similar ages to the clearly metamorphic zircon phases.

Chipera gabbro yielded a relatively small amount of brown pyroxene and abundant fresh plagioclase. The Sm-Nd data (App. 3 and Fig. 4A) yield an iso-chron, which gives an age of 1047 ± 29 Ma for the

gabbro. The initial ratio of +1.4 is still much lower than the coeval depleted mantle, which according to the model by DePaolo (1981), for example has an εNd(1047 Ma) of +5.6.

Monte Capirimpica granite has abudant brown, transparent to translucent, prismatic (l:w = 3–4) zir-con. The population is quite homogeneous and the zircon mostly medium grained with a rather even size distribution.

Four zircon fractions were dated using TIMS

(App. 2). The zircon has a moderate U concentra-tion and varying 206Pb/204Pb ratios, one being rather low. The radiogenic 208Pb/206Pb ratios are uniform. On the concordia diagram (Fig. 3P), the four frac-tions plot well on the same discordia line with an upper intercept age of 1086 ± 7 Ma.

In aplite granite Mos-19, the zircon content of the nonmagnetic fraction is extremely low and the population looks quite heterogeneous in terms of outlook and grain size. The fine-grained zircon is transparent, colourless to brownish and has either tabular or oval to prismatic morphology. The larger grains are either turbid and dark brown or transpar-ent and quite colourless. The shapes vary from short prismatic to longer crystals. The number of flat, rounded grains is significantly high. The magnetic fraction contains abundant dark brown, turbid, paler coloured, and translucent zircon, principally with a euhedral shape. The zircon in CL (Fig. 2) shows a variety of internal structures. Most of the rounded and flat grains have a CL-dark and spotty internal structure with sporadic CL-paler rims and spots in-side. In addition, there are clearly-zoned crystals with or without structurally homogeneous rim do-mains.

Using SHRIMP, a total of 21 zircon domains were dated (App. 1). One analysis was rejected due to a high common lead content. On the concordia

diagram (Fig. 3Q), the data divide into two main age groups. The older data, including both zoned (n = 11) zircon domains and metamorphic, homo-geneous rims and their metamict core domains (n = 4), plot roughly between 850 Ma and 800 Ma. These data seemingly split further into two sub-clusters. However, because the Pb/Pb ages are over-lapping, all the data are considered as a single age group. The weighted average of the 207Pb/206Pb ages for the zoned zircon only is 867 ± 15 Ma (Fig. 3Q). The younger group includes five analyses: three de-termines a concordia age of 512 ± 4 Ma and two show slightly older ages. All these show an excep-tionally low Th/U ratio.

In summary, the zircon crystallized at 867 ± 15 Ma. Approximately coevally at 850–830 Ma, the flat, round, and metamict zircon suffered radiogenic lead loss (see Fig. 2; zircon 3). This zircon feasibly has a sedimentary origin and its initial age is un-known, as the U-Pb system of a metamict zircon is easily affected by hydrothermal events. Cambrian metamorphism at 512 ± 4 Ma is evident.

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Mos-20 / 2943-04 Garnet-sillimanite gneiss, Rushinga Group

Mos-21 / 1519-04 Fudeze orthogneiss, Mudzi Metamorphic Complex

Rushinga Group garnet-sillimanite gneiss yield-ed a small amount of zircon with a fine and uniform grain-size. The general tone is quite pinkish but sin-gle crystals are almost colourless, transparent, and elongated. Zircon shows either clear crystal faces or the surfaces are quite smooth. The darker grains are translucent. It is supposed that the older grains are healed/metamorphosed to transparent, colour-less grains. Almost every one of the mounted zir-con grains is enveloped by a CL-bright rim (Fig. 2). The mostly CL-dark inner/core domains are either altered or show compositional zoning. A few zoned cores are surrounded first by a CL-dark phase and secondly by a thin CL-bright rim (Fig. 2).

Using SHRIMP, 17 zircon domains were dated (App. 1). Two analyses have high common lead contents and were therefore rejected. On the ccon-cordia diagram (Fig. 3R), the U-Pb data divide into four separate groups: 1) Five concordant or slightly discordant, low Th/U analyses determine a concor-dia age of 518 ± 6 Ma. These youngest ages were measured from either CL-bright rims or CL-dark, compositionally zoned or homogeneous zircon do-mains (Fig. 2). 2) Four discordant data points from

zircon cores and grains fall on the same discordia line. Calculating these data solely or combined with the ~500 Ma data, the upper intercept age will be ~2.0 Ga. 3) Five discordant analyses from cores enveloped by CL-bright rims determine an upper intercept age of ~2.54 Ga when calculated with or without the youngest ~500 Ma data. 4) The highly discordant analysis (1.2; see also Fig. 2) from a CL-dark zoned core has a 207Pb/206Pb age of ~2.7 Ga and the enveloping CL-bright rim plots in the ~500 Ma group. When plotted together, an age of ca. 2.8 Ga can be estimated for the zircon core.

From the limited available age data, it is clear that the provenance is composed at least from rocks with ages of ~2.8 Ga, ~2.5 Ga, and ~2.0 Ga. The maximum age for sedimentation would be ~2.0 Ga. On the other hand, as the U-Pb data are highly dis-cordant and the metamorphism at ~500 Ma could have shifted the older data points slightly, the ages should only be considered as rough estimates. The concordia age of 518 ± 6 Ma (Fig. 3R) determined by analyses from the low Th/U and CL-bright zir-con rims records Pan-African metamorphism. This age is also a minimum age for the sedimentation.

Fudeze orthogneiss contains abundant pris-matic zircon with a varying grain size. The popu-lation looks homogeneous and only the degree of colour and brightness varies between the smallest and the largest zircons. The zircon shows composi-tional zoning in CL images (Fig. 2). A few inherited cores were detected. However, with the few excep-tions they are too small or altered for reliable U-Pb dating.

Using SHRIMP, a total of 16 zircon domains were dated (App. 1). One analysis has a high com-mon lead content and was therefore rejected. Unfor-tunately, this analysis was the only one from a thin CL-bright zircon rim. Furthermore, the four most

discordant data are ignored in this context. On the concordia diagram (Fig. 3S), the concordant and nearly concordant U-Pb data plot mostly between 2.6 and 2.8 Ga. Four discordant and two concordant analyses on zoned zircon define a discordia line that intercepts the concordia curve at ~2.59 Ga.

In addition to ~2.6 Ga zircon, five older ages be-tween 3.05 Ga and 2.65 Ga were measured from zoned zircon and an inherited core. These commonly also show higher Th/U compared to those of the ~2.6 Ga zircon. The apparent core in zircon 1 has a 207Pb/206Pb age of 3.05 Ga, whereas the main zircon domain belongs to the ~2.6 Ga age group (see Fig. 2). Thus, the age for the Fudeze orthogneiss is ~2.59 Ga.

Mos-22 / 2893-04 granite, Rukore Suite

Rukore granite yielded abundant zircon with a homogeneous population. The long to short crys-tals are mainly transparent, almost colourless, have clear crystal faces, and occasionally contain dark inclusions.

Three zircon fractions were dated using TIMS (App. 2). Two of them give concordant Lower Jurassic ages (Fig. 3T). As the Pb-U data from the

two individual, young, and low-U fractions are not exactly equal, the results may indicate some uncer-tainty within Pb and U fractionation during the mass spectrometry. Therefore, it is suggested that an age approximation of 195–180 Ma is used for the gran-ite. The third analysis (B) is discordant and suggests the involvement of some older lead.

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Mos-23 / 13625-04 tonalite, Mavonde Complex

Mos-24 / 15273-04 syenite, Gorongosa Intrusive Suite

Mos-25 / 25416-04 dolerite, Archaean terrain

Mos-26 / 1011-02 garnet gneiss, Gairezi Group

The zircon content of the Mavonde Complex tonalite is anomalously low. The very fine-grained zircon is largely brown, transparent, and prismatic. The large grains are either white to yellowish, totally turbid, and stubby or dark brown, translucent/trans-parent, prismatic (stubby to l:w ≤ 4). In CL images (Fig. 2), most of the zircons show clear magmatic zoning. A few are totally altered (turbid whitish/yel-lowish) and altered inherited cores are thought to be quite common.

The SHRIMP U-Pb age results from the tonalite are quite unambiguous and therefore only 12 anal-

yses were carried out (App. 1). On the concordia diagram (Fig. 3U), the ten concordant or nearly con-cordant analyses from magmatic, zoned zircon plot in a cluster at 2.9 Ga. The upper intercept age of 2907 ± 16 Ma is the age for the tonalite. Thus, this deformed tonalite is Mesoarchaean. The altered/metamict cores indicate even older zircon ages for inherited components. Two analyses give very dis-cordant age results (Fig. 3U). These were measured from a structurally rather homogeneous core and from a low Th/U zircon rim phase.

The zircon in Gorongosa syenite is mostly trans-parent to translucent, almost colourless to yellow-ish, and elongated. The crystal faces are frequently striated and the grains are preferably quite platy. In addition to this type of zircon, a small quantity of darker brown, stubby grains were detected. These

are considered as inherited.The two zircon fractions analysed using TIMS

(App. 2) give concordant and equal Lower Jurassic ages. The concordia age of 181 ± 2 Ma (Fig. 3V) determines the age for the syenite.

The dolerite Mos-25 contains abundant pyroxene and plagioclase for Sm-Nd isochron. The pyroxene is fresh, transparent, and brown. Plagioclase ranges from clear colourless to turbid white.

The Sm-Nd data (App. 3; Figs. 4B and 4D) reveal a relatively high REE level and the trend shows sig-nificant enrichment in LREE (cf. chondritic 147Sm/144Nd = 0.1966; Jacobsen and Wasserburg 1980). The whole rock, plagioclase, and pyroxene analy-

ses do not yield any decent isochron (MSWD = 17) (Fig. 4B). An anomalous feature is the relatively high Sm/Nd in the analyzed plagioclase fraction. The age of 1783 ± 51 Ma derived from the analyses on whole rock and pyroxene may be considered as the best estimate for the magmatic crystallization of the rock. The initial epsilon-value is –2.2 and sug-gests the involvement of older LREE-enriched ma-terial in the genesis of the rock.

The garnet-kyanite gneiss contains several zircon types with quite a uniform grain-size. These include: 1) transparent, colurless, round to oval and elongat-ed grains, which are at least partly metamorphic, 2) translucent to turbid, white prismatic crystals, and 3) thoroughly turbid, usually yellowish, most prob-ably metamict zircon. In CL images (Fig. 2), the zircon frequently shows compositional zoning. The few roundish, structurally fairly homogeneous zir-con grains are the clear exceptions. The CL-bright zircon rims are very few in this sample.

Using SHRIMP, 17 zircon domains were dated (App. 1). On the concordia diagram (Fig. 3W), the

majority of the U-Pb data plot on the same regres-sion line, intercepting the concordia curve at 2.06 Ga. These are mostly magmatic zircons. The lower intercept age of 0.86 Ga is quite high and therefore may indicate some real thermal event. However, as it is determined only by a few discordant data points the age is absolutely not an exact age. If well de-termined, the lower intercept age may have an im-portant role in estimating the minimum age for the sedimentation. The maximum age of 2041 ± 15 Ma for the sedimentation is determined by calculating the mean age for the 207Pb/206Pb ages of concordant data.

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Mos-27 / 14410-03 Moeza dike, Rukore Suite

Mos-28 / 19313-04 granite, Báruè Complex

In addition to ~2.04 Ga zircons, the SHRIMP age data also indicate Archaean provenances for the sed-

iment. The four Archaean zircons have 207Pb/206Pb ages of ~3.1 Ga, 2.7 Ga, and ~2.6 Ga (n = 2).

The mafic Moeza dike contains abundant py-roxene and plagioclase for Sm-Nd isochron dating with whole-rock powder. The pyroxene is fresh and brown, and the plagioclase looks somewhat hetero-geneous in transparency and colour.

The results of the Sm-Nd analyses are shown in

Appendix 3 and Figures 4B and 4D. The REE-level is high and the pattern clearly LREE enriched. The Sm-Nd analyses on minerals and whole rock yield an age of 180 ± 43 Ma, thus suggesting an age close to Jurassic Karoo basalts. The initial epsilon value of –0.3 is clearly low compared to coeval MORB.

The granite sample from Báruè Complex con-tains abundant rather homogeneous-looking zircon. The grain size of the usually stubby or short pris-matic zircon is largely fine to medium. It is totally transparent and colourless or turbid to translucent and pale brown. The larger grains are usually deep-er in colour and less transparent compared to finer-grained zircons. In CL images (Fig. 2), the mount-ed zircon shows generally compositional zoning. Moreover, evident core and rim domains are quite common.

A total of 14 zircon domains were SHRIMP dated (App. 1). Five concordant analyses from zoned zir-con crystals determine an age of 1119 ± 21 Ma (Fig. 3X). The older zircon domains have ages of ~1.83 Ga, 2.03–2.05 Ga, and 2.50 Ga. For the most part these were dated from cores enveloped by thin, CL-dark zircon rims around them (Fig. 2). The magmat-ic age for the granite is 1119 ± 21 Ma and the older data from inherited zircon indicate either a sedimen-tary precursor or the inherited grains originate from neighbouring quartzite.

Mos-29 / 19290-04 Inchapa granodiorite, Báruè Complex

The Inchapa granodiorite yielded only a small amount of brownish, turbid to translucent, coarse- to fine-grained zircon and abundant monazite. The larger zircon grains are typically shorter prismatic and the smaller grains show long prismatic mor-phology. Among these, a few transparent and mere-ly colourless grains were detected. In CL images (Fig. 2), the short grains show oscillatory zoning. CL-dark zircon rims frequently envelope the zoned centre domains. A few completely CL-dark grains were also detected.

Using SHRIMP, 17 zircon domains were dated (App. 1). Three analyses were rejected due to high

common lead contents. On the concordia diagram (Fig. 3Y), the U-Pb data from zoned zircon largely plot at around 1100 Ma. The seven concordant anal-yses define an age of 1079 ± 7 Ma for the grano-diorite. The U-Pb data from the CL-dark rims are highly discordant, indicating lead loss from high U zircon domains

TIMS analysis of monazite gives slightly re-versely discordant age data (App. 2 and Fig. 3Y). This may be due to the excess of 206Pb from 230Th of a high Th-mineral (Schärer 1984). However, the re-sult clearly indicates the Pan–African metamorphic effect at ~520 Ma.

Mos-30 / 19140-04 Messeca granodiorite, Mavonde Complex

The zircon population in Messeca granodiorite looks rather homogeneous. Larger grains are com-pletely turbid, grey-brown, and mostly euhderal, although sub- to anhedral forms also exist. The fine-grained zircon is mostly translucent, gray-brown, and short prismatic (l:w = 2–3).

Five zircon fractions were analysed using TIMS U-Pb (App. 2). The U-Pb data are highly discordant and plot in two clusters (Fig. 3Z), in spite of the dif-ferent analysed grain-size fractions and air-abrasion times used. The practically two-point reference line intercepts the concordia curve at ~2.5 Ga and 0.56

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Mos-31 / 6845-04 Monte Chissui tonalite, Báruè Complex

MOS-32 / 13888-04 Mashonaland dolerite

MOS-33 / 4158-03 metasandstone, Zámbuè Supergroup

Ga. It may be argued that the seemingly Archaean, high-U zircon was affected by later metamorphism. Therefore, the upper intercept age of the extremely

discordant data could only be taken as a rough age estimate.

The main part of the zircon in Monte Chissui to-nalite is extremely bright, has a tint of pink colour, and is either euhedral or more oval in shaped. The length to width ratio of the crystals and grains is mostly 2 to 4. In addition to the bright ones, only a few translucent and turbid grains were detected.

The TIMS dating of four zircon fractions (App. 2 and Fig. 3Å) yielded discordant U-Pb data despite the very bright appearance of zircon. The analyses A and D plot close each other and therefore the

discordia line is practically determined by three points only. The apparent concordia intercept ages are ~1.30 Ga and 0.60 Ga. The fairly high lower intercept age most probably indicates the effect of metamorphism(s) and the discordia upper intercept may therefore have been shifted to an older age. Consequently, it is suggested that this age is consid-ered merely as a maximum age for the tonalite. The highest 207Pb/206Pb ages of ~1150 Ma would then be the minimum age for the rock.

The Mashonaland dolerite contains abundant pyroxene and plagioclase for Sm-Nd isochron dat-ing with whole-rock powder. Pyroxene in the sam-ple Mos-32 is fresh, fairly transparent and green-ish-grey. Plagioclase ranges from clear colourless to slightly turbid white. The Sm-Nd data (App.3;

Figs. 4C and 4D) reveal a relatively high level of REE in plagioclase. The data on minerals and whole rock give an age of 1102 ± 52 Ma. The initial ЄNd of –7.3 suggests major involvement of older LREE-enriched material in the genesis of this rock.

The Zámbuè Supergroup metasandstone yielded only a small amount of zircon with varying grain size. The zircon morphology varies from long pris-matic (l:w = 3–5) to oval-shaped, it is transparent to translucent, and reddish-brownish to almost colour-less. Many grains are pigmented. The zircon in CL (Fig. 2) shows a range of complex internal struc-tures. Cores are often rounded and/or corroded and surrounded by CL-dark zircon rims. There are also mixed types, from totally metamict CL-dark zircon to zoned euhedral grains. Almost all the grains are enveloped by CL-dark rims.

Eighteen zircon domains were dated using SHRIMP (Appendix 1 and Fig. 3Ä). The U-Pb data are concordant and show varying ages and Th/U ra-tios. The analyses from CL-dark rim phases show high common lead contents but only two analyses showing the highest common lead were rejected from data processing, as zircon rim data would oth-erwise be totally missing. Zoned, mostly rounded cores yield Archaean (~2.7 Ga and 2.5 Ga) and Palaeoproterozoic (2.1 Ga and 1.9 Ga) sources for the sandstone. Four analyses from zoned cores and

euhedral zircon grains plot around 1.3–1.2 Ga. Fur-thermore, a zircon rim around a rounded zoned core plots on the younger end of this group.

Three analyses plot around 1.07 Ga. Two of these analyses (1.1 and 11.1) have very high common lead contents: one comes from a younger, low Th/U zircon phase of zircon 1 and the other probably hit on marginal zone between the zoned core and rim domains. The third analysis (7.1) was performed from a zoned, CL-dark zircon.

The ~0.83 Ga age was measured from a mag-matically zoned zircon (2.1). A CL-dark, low Th/U zircon rim (Appendix 1: analysis 8.1) with a Palaeo-proterozoic rounded core indicates metamorphism at ~ 0.4 Ga. However, as this analysis shows an ex-tremely high common lead content its age result is inaccurate.

The maximum sedimentation age determined from these limited data is certainly ~1.2 Ga. The two single younger magmatic ages of ~1.07 Ga and 0.83 Ga may indicate an even younger maximum sedimentation age. Nevertheless, single data points are not considered to provide reliable evidence.

101


MOS-37 / 1714-05 dolerite, Post-Gairezi Group

MOS-34/ 3157-03 felsic/intermediate metavolcanic rock, Fíngoè Supergroup

The metavolcanic rock from Fíngoè Supergroup yielded abundant zircon. The crystals are mostly prismatic (l:w = 3–4), transparent, and either quite colourless or weakly brownish. The colourless grains contain inclusions. In CL (Fig. 2), the zircon shows oscillatory zoning. A few grains have homo-geneous zircon growth around corroded and zoned centre domains and several apparent cores were de-tected. However, due to the limited number of anal-yses the cores were ignored during dating.

Using SHRIMP, a total of 12 zircon domains were dated (App. 1). All the data are concordant or nearly concordant and the analyses are all from zoned, euhe-dral zircons. On the concordia diagram (Fig. 3Ö), the data scatter between 950 and 1400 Ma. The six oldest analyses plot in a cluster determining the con-cordia age of 1327 ± 16 Ma for the zircon crystal-lization. The younger U-Pb data most probably in-dicate lead loss connected to metamorphism at ~0.8 Ga, which is the lower intercept age of the discordia line defined by all the data (See Fig. 3Ö).

Post-Gairezi dolerite yielded garnet and transpar-ent plagioclase for Sm-Nd analyses. The quality of pyroxene was too poor for analysis. For analysis, the garnet separate was ground and leached step-wise in HCl according to the method of DeWolf et al. (1996). The Sm-Nd data (App. 3; Figs. 4C and 4D) reveal a relatively high REE level and the trend shows significant enrichment in LREE (cf. chon-dritic 147Sm/144Nd = 0.1966). Three analyses do not

plot on the same isochron. The age estimate for the garnet-whole rock pair is 503 ± 8 Ma, whereas anal-yses on plagioclase and whole rock define a slope that gives an age of 973 ± 73 Ma and an initial ep-silon value of –1.3. Provided that the plagioclase has remained as a closed system since its magmatic crystallization, the age estimate for the dike is 973 ± 73 Ma. The ~500 Ma is consistent with the Pan-African metamorphism.

SUMMARY OF THE AGE RESULTS

General summary

This report presents isotopic ages for 35 rock samples from NW Mozambique sampled during geological mapping of the LOT 2 area. The age range of felsic to mafic magmatic rocks varies from 2.91 Ga to 0.18 Ga. Several samples have ~500 Ma low Th/U zircon phases evidencing Pan-African

metamorphism. An indication for the existence of a ~3.1 Ga protolith was found from two samples. The age data and comments on these are summarized in Table 2 and the age distribution of 32 supposedly magmatic rock samples is illustrated in Figure 5.

Archaean domain – Zimbabwe craton

The Archaean Zimbabwe craton extends margin-ally into Mozambique. The oldest dated rock with a zircon U-Pb age of 2907 ± 16 Ma is a tonalite located near the town of Manica, south of the Mani-ca greenstone belt. No inherited zircon was found from this tonalite. Four apparently Archaean ages of 2.71-2.50 Ga were dated from TTG gneisses lo-cated in southern to northern parts of the Archaean domain. 3.1 Ga and 2.7 Ga inherited zircon grains were found from the 2.60 Ga orthogneiss. Further-more, the 2.71 Ga gneiss has metamorphic zircon

domains indicating either metamorphism or a pro-longed thermal history at ca. 2.54 Ga and finally Pan-African metamorphism at 520 ± 16 Ma.

A Palaeoproterozoic Sm-Nd mineral age of ~1.8 Ga was measured for a dolerite intruding the Ar-chaean Manica greenstones. An initial ЄNd of –2.2 suggests the involvement of older LREE-enriched material in the genesis of the rock. Garnet in ~1.0 Ga dolerite crosscutting the Palaeoproterozoic Gai-rezi mica schist within the Archaean domain reflects Pan-African metamorphism at ~500 Ma. Palaeopro-

102


Tabl

e 2.

Sum

mar

y of

the

age

resu

lts, s

ampl

es fr

om N

W M

ozam

biqu

e.

LA

BID

FIE

LD

NU

MB

ER

RO

CK

TY

PESU

ITE

/G

RO

UP

DA

TIN

GM

ET

HO

DA

GE

RE

SUL

TA

GE

TY

PE, N

UM

BE

R O

F FR

AC

TIO

NS,

ET

C.

AG

ER

EM

AR

KS

Mos

-110

55-0

2G

rani

te g

neis

sR

io C

apoc

he

gran

iteSH

RIM

PU

-Pb

1201

±10

Ma

Con

cord

ia a

ge; n

=5/1

1; z

oned

zirc

onM

agm

atic

age

6/11

ana

lyse

s sho

w le

ad lo

ss a

t 105

0−11

50 M

a.

Mos

-222

53-0

3M

onte

Dom

be

gran

iteC

assa

catiz

aSu

iteTI

MS

U-P

b11

02 ±

24

Ma

Upp

er in

terc

ept a

ge; n

= 4/

4 ~M

agm

atic

age

H

eter

ogen

eous

zirc

on p

opul

atio

n. M

SWD

=4.4

. R

athe

r dis

cord

ant P

b/U

dat

a. M

axim

um a

ge?

Mos

-310

24-0

2A

plite

gra

nite

Gur

o B

imod

al

Suite

SHR

IMP

U-P

b85

2 ±

15 M

aM

ean

of 20

7 Pb/20

6 Pb a

ges;

n=1

5/15

Mag

mat

ic a

geA

ge d

ata

scat

ter b

etw

een

760

and

920

Ma.

R

ims t

oo th

in fo

r rea

sona

ble

datin

g

Mos

-410

72-0

2A

plite

gra

nite

Gur

o B

imod

al

Suite

TIM

SU

-Pb

867

± 9

Ma

Upp

er in

terc

ept a

ge; n

= 4/

4 M

agm

atic

age

MSW

D=1

.0

Mos

-510

97-0

3G

rani

teC

haco

com

agr

anite

SHR

IMP

U-P

b10

46±

20 M

aM

ean

of 20

7 Pb/20

6 Pb a

ges;

n=1

4/15

; m

ostly

zon

ed z

ircon

Mag

mat

ic a

geA

ge d

ata

scat

ter b

etw

een

960

and

1080

Ma.

A fe

w th

in, l

ow T

h an

dU

met

amor

phic

zirc

on ri

ms a

re c

oeva

l with

the

mag

mat

ic z

ircon

gr

ains

. One

zirc

on sh

ows a

n ap

pare

ntly

hig

her 20

7 Pb/20

6 Pb a

ge o

f ca

. 1.2

Ga.

M

os-6

1170

-03

Mas

sang

agn

eiss

Mud

ziM

etam

orph

icC

ompl

ex

TIM

SU

-Pb

~2.6

3 G

aU

pper

inte

rcep

t age

; n=

3/3

Mag

mat

ic a

ge

(met

amor

phic

?)A

ctua

lly, a

lmos

t a tw

o po

int l

ine.

No

mat

eria

l for

furth

er a

naly

ses.

Just

a ro

u gh

age

estim

ate.

Mos

-712

84-0

3G

neis

sM

udzi

Met

amor

phic

Com

plex

SHR

IMP

U-P

b~2

.71

Ga

~2.5

4 G

a

520

± 16

Ma

Upp

er in

terc

ept a

ge;

n= 6

/6; z

oned

Upp

er in

terc

ept a

ge: n

=4/6

; m

etam

orph

ic g

rain

s,rim

Con

cord

ia a

ge: n

=2/2

; Cl-b

right

, low

Th

/U ri

ms

Mag

mat

ic a

geM

etam

orph

ic a

ge?

Met

amor

phic

age

~2.

70−2

.72

Ga

zirc

ons.

Scat

terin

g an

d ov

erla

ppin

g m

agm

atic

and

met

amor

phic

age

dat

a.

Mos

-824

50-0

3G

rani

teM

acan

gaG

rani

teSH

RIM

PU

-Pb

470

± 14

Ma

Mea

n of

207 Pb

/206 Pb

age

s; n

=13/

14;

zone

dM

agm

atic

age

?M

etam

orph

ic a

ge?

The

fact

s tha

t the

Pb/

U d

ata

scat

ter b

etw

een

350

Ma

and

650

Ma

and

zirc

ons s

how

Cl-d

ark,

som

etim

es b

lurr

y in

tern

al st

ruct

ure

may

si

gnify

dis

turb

ing

of th

e or

igin

al m

agm

atic

age

.M

os-9

2007

-03

Gra

nite

Cas

saca

tiza

Suite

TIM

SU

-Pb

1077

± 2

Ma

Con

cord

ia a

ge; n

= 2/

4 M

agm

atic

age

Fr

actio

n D

onl

y sl

ight

ly d

isco

rdan

t but

not

equ

al w

ith A

and

B

frac

tions

. C is

cle

arly

dis

cord

ant .

Mos

-10

2001

-02

Gra

nite

Mon

te S

anja

Su

iteTI

MS

U-P

b10

50 ±

8 M

aU

pper

inte

rcep

t age

; n=

4/4

Mag

mat

ic a

ge

MSW

D=0

.3. L

ow 20

6 Pb/20

4 Pb ra

tios.

Mos

-11

2297

-03

Des

aran

ham

agr

anite

Fura

ncun

goSu

iteTI

MS

U-P

b10

41 ±

4 M

aU

pper

inte

rcep

t age

; n=

4/4

Mag

mat

ic a

ge

MSW

D=1

.0

Mos

-12

4493

-03

Gra

nite

Sind

a Su

iteSH

RIM

PU

-Pb

502

± 8

Ma

Con

cord

ia a

ge; n

=14/

15; m

ostly

zon

edM

agm

atic

age

R

epla

cing

stru

ctur

ally

hom

ogen

eous

zirc

on p

hase

and

zon

ed c

ore

dom

ains

are

coe

val .

Mos

-13

6035

-03

Gra

nite

Cas

tanh

oG

rani

teTI

MS

U-P

b10

50 ±

2 M

aC

onco

rdia

age

; n=3

/4M

agm

atic

age

O

ne fr

actio

n sl

ight

ly d

isco

rdan

t but

plo

ts o

n a

sam

e cl

uste

r.

Mos

-14

2395

-03

Gab

bro

Atc

hiza

Sui

teSm

-Nd

864±

30

Ma

Min

eral

isoc

hron

age

; n=3

; py

roxe

ne+p

lagi

ocla

se+w

hole

-roc

kM

agm

atic

age

In

itial

eN

d = −3

.0

Mos

-15

4241

-03

Gra

nite

Cas

saca

tiza

Suite

SHR

IMP

U-P

b11

17 ±

12

Ma

Con

cord

ia a

ge; n

=10/

14; m

ostly

zon

ed

zirc

on d

omai

n sM

agm

atic

age

103


Tabl

e 2.

Con

tinue

d.

LA

BID

FIE

LD

NU

MB

ER

RO

CK

TY

PESU

ITE

/G

RO

UP

DA

TIN

GM

ET

HO

DA

GE

RE

SUL

TA

GE

TY

PE, N

UM

BE

R O

F FR

AC

TIO

NS,

ET

C.

AG

ER

EM

AR

KS

Mos

-16

1301

6-03

Gra

nite

gne

iss

Mat

unda

Sui

teSH

RIM

PU

-Pb

784

± 36

Ma

528

± 4

Ma

Mea

n of

207 Pb

/206 Pb

age

s; n

=6; m

ostly

zo

ned

zirc

on d

omai

nsC

onco

rdia

age

; n=3

/6 (r

im, t

ip, m

etam

ict

grai

n - a

ll lo

w T

h/U

)

Age

s for

zon

ed

zirc

on d

omai

nsM

etam

orph

ic a

ge

The

olde

r dat

a sc

atte

r rou

ghly

bet

wee

n 70

0 an

d 85

0 M

a.

The

met

amic

t gra

ins m

ost p

roba

bly

even

old

er!

One

zirc

on h

as a

207 Pb

/206 Pb

age

of c

a. 0

.9 G

a (o

lder

?).

Mos

-17

1301

4-03

Gab

bro

Chi

pera

Mas

sif

Sm-N

d10

47±

29 M

aM

iner

al is

ochr

on a

ge; n

=3;

pyro

xene

+pla

gioc

lase

+who

le-r

ock

Mag

mat

ic a

ge

Initi

al e

Nd

=+1.

4

Mos

-18

1303

2-03

Gra

nite

Mon

teC

apiri

mpi

cagr

anite

TIM

SU

-Pb

1086

± 7

Ma

Upp

er in

terc

ept a

ge; n

=4/4

Mag

mat

ic a

ge

MSW

D=0

.03

Mos

-19

2638

-04

Apl

ite g

rani

teG

uro

Bim

odal

Su

iteSH

RIM

PU

-Pb

867±

15 M

a

512±

4 M

a

Mea

n of

207 Pb

/206 Pb

age

s; n

=11;

all

zone

dC

onco

rdia

age

; n=3

/5; l

ow T

h/U

Mag

mat

ic a

ge?

Met

amor

phic

age

Con

tain

s als

o fla

t, ro

unde

d de

trita

l-typ

e m

etam

ict z

ircon

gra

ins

show

ing

now

eith

er 8

50-8

00 M

a or

~50

0 M

a ag

es.

Mos

-20

2943

-04

Gar

net-

silli

man

itegn

eiss

Rus

hing

aG

roup

SHR

IMP

U-P

b2.

0 G

a

518±

6 M

a

Upp

er in

terc

ept a

ge o

f you

nges

t det

rital

zi

rcon

gra

ins

Con

cord

ia a

ge; n

=3/5

; low

Th/

U

Max

imum

sedi

men

tatio

n ag

eM

etam

orph

ic a

ge

Prov

enan

ces:

ca.

2.8

Ga,

2.5

Ga,

and

2.0

Ga

~500

Ma

min

imum

age

for s

edim

enta

tion

Mos

-21

1519

-04

Fude

zeor

thog

neis

sM

udzi

Met

amor

phic

Com

plex

SHR

IMP

U-P

b~2

.59

Ga

Upp

er in

terc

ept a

ge; n

=6; a

ll zo

ned

zirc

ons

Mag

mat

ic a

geIn

herit

ed z

ircon

s ~2.

7 an

d ~3

.1 G

a

Mos

-22

2893

-04

Gra

nite

Ruk

ore

Suite

TIM

SU

-Pb

195−

180

Ma

Con

cord

ia a

ge; n

=2M

agm

atic

age

The

two

data

poi

nts a

re n

ot e

xact

ly e

qual

Mos

-23

1362

5-04

Tona

lite

Mav

onde

Com

plex

SHR

IMP

U-P

b29

07±1

6 M

aU

pper

inte

rcep

t age

; n=1

0/12

; all

zone

d zi

rcon

sM

agm

atic

age

No

inhe

rited

age

s for

zirc

ons.

Mos

-24

1527

3-04

Syen

iteG

oron

gosa

Intru

sive

Sui

teTI

MS

U-P

b18

1±2

Ma

Con

cord

ia a

ge; n

=2M

agm

atic

age

Mos

-25

2541

6-04

Dol

erite

Arc

haea

nte

rrai

nSm

-Nd

1783

±51

Ma

Min

eral

isoc

hron

age

; n=2

; py

roxe

ne+w

hole

-roc

kM

agm

atic

age

Initi

al e

Nd

=−2.

2. P

lagi

ocla

se a

nom

alou

s (hi

gh S

m/N

d).

Mos

-26

1011

-02

Gar

net g

neis

sG

aire

zi G

roup

SHR

IMP

U-P

b20

41 ±

15

Ma

~0.8

5 G

a

Mea

n of

207 Pb

/206 Pb

age

s; n

=6; m

ostly

zo

ned

Low

er in

terc

ept a

ge

Max

imum

sedi

men

tatio

n ag

eLe

ad lo

ss

Prov

enan

ces:

3.1

Ga,

2.7

-2.6

Ga,

and

2.0

Ga

Min

imum

sedi

men

tatio

n ag

e?

Mos

-27

1441

0-03

Dol

erite

Moe

za D

ike,

R

ukor

e Su

iteSm

-Nd

180±

43 M

aM

iner

al is

ochr

on a

ge; n

=3;

plag

iocl

ase+

pyro

xene

+who

le-r

ock

Mag

mat

ic a

geIn

itial

eN

d = −0

.2.

Mos

-28

1931

3-04

Gra

nite

Bár

uèC

ompl

e xSH

RIM

PU

-Pb

1119

±21

Ma

Con

cord

ia a

ge; n

=5; a

ll zo

ned

Mag

mat

ic a

geIn

herit

ed z

ircon

s ~2.

5 G

a, ~

2.03

Ga,

and

~1.

83 G

a

Mos

-29

1929

0-04

Inch

apa

gran

odio

rite

Bár

uèC

ompl

exSH

RIM

PTI

MS

U-P

b

1079

±7 M

a~5

20 M

aC

onco

rdia

age

; n=7

; all

zone

d zi

rcon

sM

onaz

ite; n

=1M

agm

atic

age

Met

amor

phic

age

No

inhe

rited

zirc

on.

Slig

htly

reve

rsel

y di

scor

dant

dat

a po

int.

104


rock

LA

BID

FIE

LD

NU

MB

ER

RO

CK

TY

PESU

ITE

/G

RO

UP

DA

TIN

GM

ET

HO

DA

GE

RE

SUL

TA

GE

TY

PE, N

UM

BE

R O

F FR

AC

TIO

NS,

ET

C.

AG

ER

EM

AR

KS

Mos

-30

1914

0-04

Mes

seca

gran

odio

rite

Mav

onde

Com

plex

TIM

SU

-Pb

~2.5

Ga

(?)

Ref

eren

ce li

ne in

terc

ept a

ge; n

=5

Low

er in

terc

ept a

t ~0.

5 G

a

Mag

mat

ic a

ge w

ith

effe

ct o

f ~0.

5 G

a m

etam

orph

ism

?

Inac

cura

te a

ge: h

ighl

y di

scor

dant

dat

a, p

ract

ical

ly a

two

poin

t lin

e,

affe

cted

by

~0.5

Ga

met

amor

phis

m. S

IMS

datin

g is

nee

ded

to so

lve

the

prob

lem

.

Mos

-31

6845

-04

Mon

te C

hiss

ui

tona

lite

Bár

uèC

ompl

exTI

MS

U-P

b~1

.3 G

a (~

1.15

Ga)

Upp

er in

terc

ept a

ge; n

=4(H

ighe

st20

7 Pb/20

6 Pb a

ge)

~Mag

mat

ic a

geD

isco

rdan

t dat

a w

ith a

nom

alou

sly

high

low

er in

terc

ept a

ge.

Ther

efor

e, th

e up

per i

nter

cept

age

may

be

too

high

.

Mos

-32

1388

8-04

Dol

erite

Mas

hona

land

dole

rite

(Pos

t-U

mko

ndo)

Sm-N

d11

02±5

2 M

aM

iner

al is

ochr

on a

ge;

plag

iocl

ase+

pyro

xene

+who

le-r

ock

Mag

mat

ic a

geIn

itial

eN

d = −7

.3.

Mos

-33

4158

-03

Met

a-sa

ndst

one

Zám

buè

Supe

rgro

upSH

RIM

PU

-Pb

1.2

(-1.

3) G

an=

4 (z

oned

dom

ains

)M

axim

umse

dim

enta

tion

age

Sing

le a

naly

ses o

n zo

ned

zirc

ons a

t 1.0

7 G

a an

d 0.

83 G

a? D

etrit

al

core

s 2.7

Ga,

2.5

2 G

a, 2

.1 G

a, a

nd 1

.3-1

.2 G

a. M

etam

orph

ic z

ircon

do

mai

ns a

t ~1.

2, ~

1.07

, and

~0.

4 G

aM

os-3

431

57-0

3Fe

lsic

/in

term

edia

tem

etav

olca

nic

Fíng

oèSu

preg

roup

SHR

IMP

U-P

b13

27 ±

16 M

aC

onco

rdia

age

; n=6

; zon

ed z

ircon

Mag

mat

ic a

geA

nom

alou

sly

high

low

er in

terc

ept a

ge o

f ~0.

8 G

a m

ay in

dica

te le

a dlo

ss a

t tha

t tim

e.

Mos

-37

1714

-05

roc k

Dol

erite

Post

-Gai

rezi

dole

rite

Sm-N

d~1

.0 G

a

~500

Ma

Min

eral

isoc

hron

age

: pla

gioc

lase

+

who

le-r

ock

Min

eral

isoc

hron

age

: gar

net +

who

le-

Mag

mat

ic a

ge

Met

amor

phic

age

Tabl

e 2.

Con

tinue

d.

105


Mesoproterozoic domains – Grenvillian orogeny

Fig. 5. Age distribution of magmatic (n = 32) and metamorphic (n = 5) ages, samples from NW Mozambique. Corresponding major tectonic events are also indicated.

terozoic Gairezi Group garnet gneiss and Rushinga Group garnet-sillimanite gneiss indicate a maxi-mum sedimentation age of ~2.0 Ga and additionally

Archaean provenances. These sedimentary rocks suffered metamorphism at ~0.85 Ga and at 518 ± 6 Ma.

Báruè Complex

This Mesoproterozoic unit is tectonically em-placed to its present position in the central and southern part of the LOT2 area. A 1.12 Ga granite (Mos-28) intruding quartzite contains 2.50 Ga, 2.03 Ga, and 1.8 Ga inherited zircon grains. Further, a granodiorite east of Inchapa has a zircon age of 1079 ± 7 Ma and Pan-African metamorphism is indicated by ~520 Ma monazite. The age for the Monte Chis-sui tonalite is poorly constrained and estimated to be 1.15–1.30 Ga.

Area north of the E–W trending Zambezi rift covering the northern part of Tete Province

A felsic/intermediate volcanic rock from the Fín-goè Supergroup yields a zircon U-Pb age of 1327 ± 16 Ma with an anomalous lower intercept age of ~0.8 Ga, possibly reflecting a thermal event at

that time. The few dated detrital zircon cores from Zámbuè Supergroup metasandstone definitely indi-cate a 1.3–1.2 Ga maximum sedimentation age and additional 2.7 Ga, 2.52 Ga, and 2.1 Ga sedimenta-tion provinces. The two single younger magmatic ages of ~1.07 Ga and 0.83 Ga may indicate an even younger maximum sedimentation age.

The following lists of granite ages show that all the dated granitic rocks are younger than the Fíngoè Supergroup. A Rio Capoche granite has a zircon U-Pb age of 1201 ± 10 Ma. Zircon from granite be-longing to the Cassacatiza Suite has an age of 1117 ± 12 Ma. Six other granites show ages clustering between 1.10 Ga and 1.04 Ga. These are ~1.10 Ga Ma Monte Dombe granite, 1086 ± 7 Ma Monte Ca-pirimpica granite, 1077 ± 2 Ma Cassacatiza granite, 1050 ± 2 Ma Castanho granite, 1050 ± 8 Ma gran-ite from the Monte Sanja Suite, and 1041 ± 4 Ma Desaranhama granite from the Furancungo Suite. A gabbro sample from Chipera Massif equivalent to

0

400

800

1200

1600

2000

2400

2800

3200

Age

/ M

a

MAGMATIC AGES: n=32METAMORPHIC AGES: n=5 data-point error symbols are 2s

Archaean Zimbabwe Craton

Palaeoproterozoic Ubendian orogenic belt, late phase

Mesoproterozoic Grenvillian (Kibaran) orogeny

Neoproterozoic Early Pan-African

Pan-African orogeny

Jurassic Karoo event

106


Neoproterozoic Suites – Early phases of Pan African orogeny

the Tete Suite has a Sm-Nd mineral age of 1047 ± 29 Ma and an ЄNd of +1.4.

Others

South of the Tete Suite mafic and ultramafic plu-tonic rocks, a Chacocoma granite yielded a Pb-Pb

mean age of 1046 ± 20 Ma. Further to the south of the LOT2 area, a sill-like Mashonaland dolerite intruding Umkondo metasediments yields an age of 1.1 Ga with an ЄNd value of –7.3, indicating major involvement of LREE-enriched material in the ge-nesis of this rock.

Palaeozoic and Mesozoic Suites

ACKNOWLEDGEMENTS

Guro Bimodal Suite

Three aplite granites in Guro Bimodal Igneous Suite, close to the northern part of the Archaean ter-rain, yield zircon ages of 867 ± 9 Ma, 852 ± 15 Ma, and 867 ± 15 Ma. Pan-African metamorphism at 512 ± 4 Ma is evidenced by low Th/U metamorphic zircon domains.

Atchiza and Matunda Suites

Atchiza Suite gabbro, NW of the lake Cahora Bassa in the northern part of the LOT 2 area, has an age of ~ 860 Ma and an ЄNd of -3.0. The mean Pb-Pb age for the Matunda Suite gneiss located west of the Atchiza gabbro is ~ 0.8 Ga, but the oldest magmatic zircon is 0.85 Ga. 528 ± 4 Ma metamorphic zircon domains indicate the strong effect of Pan-African metamorphism.

Pan-African felsic intrusive rocks

Two Palaeozoic granites intruding the Mesopro-terozoic northern part of the LOT2 area, N of Tete Province have ages of 470 ± 14 Ma and 502 ± 8 Ma.

Karoo event

Three samples show Jurassic Karoo igneous ages.

A syenite from the Gorongosa Intrusive Suite in-truding the Mesoproterozoic Báruè Complex has an age of 181 ± 2 Ma. Granite of the Rukore Suite in-truding the Palaeoproterozoic Rushinga Group su-pracrustals next to the Zimbabwe border yields an age of 195–180 Ma. A N–S trending Moeza dyke in Mesoproterozoic bedrock north of Tete has a Sm-Nd age of 180 ± 43 Ma with an initial ЄNd of –0.3.

The personnel, namely A. Larionov, D. Matukov, S. Presniakov, and N. Rodionov of CIR/VSEGEI in St. Petersburg, are thanked for the SHRIMP anal-yses. H. Huhma was responsible for the Sm-Nd analyses, A. Pulkkinen helped with the mass spec-trometry, and E. Kuosmanen produced the geologi-cal map. They are all thanked. M. Karhunen, M. Niemelä, and T. Hokkanen all from GTK are warmly

thanked for rock crushing and milling, heavy min-eral separation, and laboratory work, respectively. Last but definitively not least, I am grateful to the project geologists who did the sampling and helped with the geological aspects, to R. Lahtinen for the manuscript review, to P. Hölttä and A. B. Westerhof for comments on manuscript, and to R. Siddall for revising the English.

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108


App

endi

x 1.

Zirc

on S

HR

IMP

U-P

b is

otop

ic d

ata,

sam

ples

from

NW

Moz

ambi

que.

Spo

tD

ated

zir

con

dom

ain

% 206 Pb

c

ppm

Upp

mT

h

232 T

h/23

8 Upp

m20

6 Pb*

(1)

206 Pb

/238 U

Age

(1)

207 Pb

/206 Pb

Age

% Dis

-co

r-da

ncy

(1)

207 Pb

*

/206 Pb

*±%

(1)

207 Pb

*

/235 U

±%(1

)20

6 Pb*

/238 U

±%er

rco

rr

Mos

-1 /

1055

-02

Rio

Cap

oche

gra

nite

gne

iss

MO

S-1.

1.1

quite

hom

ogen

eous

, CL-

brig

ht c

ore

dom

ain

3.80

2913

0.48

510

87±2

413

55±3

4025

0.08

7018

.02.

200

18.0

0.18

362.

40.

13M

OS-

1.1.

2zo

ned,

CL-

dark

tip

dom

ain

0.17

754

520.

0712

311

21±

411

17±

190

0.07

69 0

.92.

012

1.0

0.18

980.

40.

38M

OS-

1.2.

1zo

ned,

CL-

med

ium

0.92

4927

0.56

911

98±1

712

51±1

304

0.08

22 6

.8

2.32

0 6

.90.

2042

1.5

0.22

MO

S-1.

3.1

zone

d, C

L-m

ediu

m0.

4915

392

0.62

2712

10±

911

79±

52-3

0.07

93 2

.6

2.25

8 2

.80.

2065

0.8

0.29

MO

S-1.

4.1

zone

d, C

L-br

ight

cen

tre

dom

ain

7.23

146

0.48

312

16±3

7 8

25±6

40-3

20.

0670

31.0

1.91

031

.00.

2077

3.3

0.11

MO

S-1.

5.1

zone

d, C

L-br

ight

cen

tre

dom

ain

5.27

219

0.47

411

92±2

612

61±3

806

0.08

3019

.02.

310

19.0

0.20

322.

40.

12M

OS-

1.6.

1zo

ned,

CL-

pale

cen

tre d

omai

n1.

7051

210.

439

1191

±14

1171

±150

-20.

0789

7.4

2.

210

7.5

0.20

301.

30.

18M

OS-

1.7.

1zo

ned,

CL-

pale

cen

tre

dom

ain

3.23

157

0.47

313

59±2

615

73±2

2016

0.09

7012

.03.

150

12.0

0.23

472.

20.

18M

OS-

1.8.

1zo

ned,

CL-

pale

cen

tre

dom

ain

3.20

3422

0.65

612

09±1

710

32±2

10-1

50.

0736

11.0

2.09

011

.00.

2062

1.6

0.15

MO

S-1.

9.1

zone

d, C

L-br

ight

cen

tre

dom

ain

4.29

1910

0.56

311

74±2

713

26±3

9013

0.08

5020

.02.

350

20.0

0.19

972.

50.

12M

OS-

1.10

.1zo

ned,

CL-

dark

, tip

dom

ain

0.55

316

960.

3156

1207

± 6

1136

± 38

-60.

0776

1.9

2.

260

2.0

0.20

600.

60.

28M

OS-

1.11

.1zo

ned,

CL-

dark

, tip

dom

ain

0.81

169

170.

1027

1094

± 7

1028

± 58

-60.

0735

2.9

1.

874

3.0

0.18

490.

70.

23M

OS-

1.12

.1zo

ned

Cl-d

ark

0.67

182

790.

4532

1187

± 9

1190

± 5

30

0.07

97 2

.72.

222

2.8

0.20

220.

80.

28M

OS-

1.13

.1zo

ned,

CL-

pale

cen

tre

dom

ain

5.54

125

0.41

211

25±4

4 2

50±1

200

-77

0.05

1051

.01.

350

52.0

0.19

084.

20.

08M

OS-

1.14

.1zo

ned

Cl-d

ark

0.34

353

400.

1254

1056

± 6

1056

± 3

50

0.07

45 1

.71.

829

1.9

0.17

790.

70.

35M

OS-

1.15

.1zo

ned

Cl-d

ark

0.89

237

750.

3337

1061

± 7

1003

± 5

4-6

0.07

26 2

.71.

791

2.8

0.17

900.

70.

25M

OS-

1.16

.1zo

ned

Cl-d

ark

0.58

249

410.

1741

1125

± 8

1095

± 4

6-3

0.07

60 2

.31.

997

2.4

0.19

060.

80.

32M

OS-

1.17

.1zo

ned

Cl-d

ark

0.18

505

113

0.23

8211

11±

510

89±

23

-20.

0758

1.1

1.96

6 1

.20.

1882

0.5

0.38

MO

S-3

/ 102

4-02

apl

ite g

rani

te, G

uro

Suite

MO

S3.1

.1zo

ned

--36

920

70.

5848

904

± 6

863

±19

-50.

0678

0.9

1.40

81.

10.

1506

0.7

0.60

MO

S3.2

.1zo

ned

--76

325

40.

3497

891

±16

882

±36

-10.

0684

1.7

1.

399

2.6

0.14

821.

90.

74M

OS3

.3.1

zone

d--

199

106

0.55

2486

1±

785

0±2

6-1

0.06

74 1

.3

1.32

71.

50.

1428

0.8

0.54

MO

S3.4

.1zo

ned

0.03

586

208

0.37

7286

5±

684

6±2

3-2

0.06

73 1

.1

1.33

11.

30.

1436

0.7

0.55

MO

S3.5

.1zo

ned

0.03

427

245

0.59

5285

6±

684

8±2

1-1

0.06

7310

.01.

318

1.2

0.14

193

0.7

0.57

MO

S3.6

.1zo

ned

0.17

1036

485

0.48

113

767

± 6

902

±66

150.

0691

3.2

1.

203

3.3

0.12

630.

80.

24M

OS3

.7.1

zone

d (d

ark

CL)

0.16

466

233

0.52

5481

3±1

982

4±5

61

0.06

65 2

.7

1.23

33.

70.

1344

2.5

0.68

MO

S3.8

.1zo

ned

(dar

k C

L)0.

0311

8134

30.

3013

379

2±

581

9±6

73

0.06

64 3

.2

1.19

73.

30.

1308

0.7

0.20

MO

S3.9

.1zo

ned

--24

211

30.

4827

794

± 8

902

±28

120.

0691

1.3

1.

248

1.7

0.13

101.

00.

61M

OS3

.10.

1zo

ned

0.04

280

149

0.55

3383

7±

781

3±3

9-3

0.06

62 1

.9

1.26

62.

10.

1386

0.8

0.41

MO

S3.1

1.1

zone

d0.

0657

326

90.

4869

840

±11

844

±19

00.

0672

0.9

1.29

01.

70.

1392

1.4

0.84

MO

S3.1

2.1

zone

d0.

0931

119

90.

6638

845

± 6

820

±35

-30.

0664

1.7

1.

283

1.8

0.14

010.

80.

41M

OS3

.13.

1zo

ned

0.10

261

131

0.52

3286

9±

784

9±3

2-2

0.06

74 1

.5

1.34

01.

80.

1443

0.9

0.50

MO

S3.1

4.1

zone

d0.

0332

320

00.

6438

826

± 7

859

±42

40.

0677

2.0

1.

276

2.2

0.13

670.

90.

40M

OS3

.15.

1zo

ned

--18

772

0.40

2387

2±

684

1±3

1-4

0.06

71 1

.5

1.34

01.

70.

1448

0.8

0.45

109


App

endi

x 1.

Con

tinue

d.

Spo

tD

ated

zir

con

dom

ain

% 206 Pb

c

ppm

Upp

mT

h

232 T

h/23

8 Upp

m20

6 Pb*

(1)

206 Pb

/238 U

Age

(1)

207 Pb

/206 Pb

Age

% Dis

-co

r-da

ncy

(1)

207 Pb

*

/206 Pb

*±%

(1)

207 Pb

*

/235 U

±%(1

)20

6 Pb*

/238 U

±%er

rco

rr

MO

S-5

/ 109

7-03

Cha

coco

ma

gran

iteM

OS5

.1.1

rim (p

ale

CL)

0.09

105

230.

2315

973

±16

1092

±38

110.

0759

1.9

1.70

42.

60.

1629

1.8

0.69

MO

S5.1

.2co

re (z

oned

,dar

k C

L)0.

0445

716

40.

3764

979

±18

1002

±16

20.

0726

0.8

1.64

12.

20.

1640

2.0

0.93

MO

S5.2

.1co

re (d

ark

CL)

0.07

451

860.

2066

1011

±56

1041

±22

30.

0740

1.1

1.73

6.1

0.17

006.

00.

98M

OS5

.2.2

rim (m

ediu

m C

L en

velo

ped

by th

in C

L-pa

le ri

m)

0.11

127

200.

1619

1052

± 10

1058

±40

10.

0746

2.0

1.82

42.

20.

1773

1.0

0.45

MO

S5.3

.1zo

ned(

unal

tere

d)--

494

225

0.47

7510

45±

710

97±1

75

0.07

610.

91.

845

1.1

0.17

590.

70.

61M

OS5

.4.1

zone

d(un

alte

red)

0.02

600

201

0.35

9110

52±

710

55±1

30

0.07

450.

61.

821

1.0

0.17

730.

70.

75M

OS5

.5.1

zone

d(un

alte

red)

0.03

965

283

0.30

135

969

±23

1104

±30

120.

0763

1.5

1.70

72.

90.

1622

2.5

0.86

MO

S5.6

.1rim

(CL-

pale

)0.

8596

240.

2613

963

± 9

1071

±58

100.

0751

2.9

1.66

83.

10.

1611

1.0

0.33

MO

S5.6

.2co

re(d

istu

rbed

zon

ing,

dark

CL)

0.17

1212

533

0.45

171

979

± 8

955

±75

-30.

0709

3.7

1.60

43.

80.

1640

0.8

0.22

MO

S5.7

.1zo

ned

(dar

k C

L)--

995

351

0.36

148

1031

± 6

983

±36

-50.

0719

1.8

1.72

01.

90.

1735

0.7

0.36

MO

S5.8

.1zo

ned

(dar

k C

L+th

in ri

m)

0.01

547

175

0.33

8310

48±1

211

93±5

912

0.07

983.

01.

943

3.2

0.17

651.

30.

40M

OS5

.9.1

zone

d (d

ark

CL+

thin

rim

)0.

0041

712

60.

3162

1027

± 8

1064

±68

40.

0748

3.4

1.78

13.

50.

1726

0.9

0.25

MO

S5.1

0.1

zone

d(da

rk C

L)0.

0644

616

40.

3862

971

±13

1013

±16

40.

0730

0.8

1.63

51.

70.

1626

1.4

0.87

MO

S5.1

1.1

zone

d(da

rk C

L)0.

2717

454

0.32

2710

72±

810

48±3

2-2

0.07

431.

61.

852

1.8

0.18

090.

80.

46M

OS5

.12.

1zo

ned(

dark

CL)

0.05

492

154

0.32

7810

96±

6010

53±1

4-4

0.07

440.

71.

900

6.0

0.18

506.

00.

99M

OS-

7 / 1

284-

03 g

neis

s, M

udzi

Met

amor

phic

Com

plex

MO

S7.1

.1zo

ned(

osc)

0.01

284

122

0.44

116

2497

± 19

2670

± 7

60.

1819

0.4

11.8

6 1

.00.

4730

0.9

0.91

MO

S7.2

.1zo

ned(

strip

ed)

0.06

318

204

0.66

110

2184

± 35

2585

± 22

160.

1728

1.3

9

.610

2

.30.

4033

1.9

0.82

MO

S7.3

.1rim

(hom

og,C

L-pa

le+d

ark

core

)0.

0428

497

0.35

8418

97±1

1024

69±

2523

0.16

12 1

.5

7.6

10

6.6

0.34

206.

40.

97M

OS7

.4.1

zone

d(os

c)0.

0151

863

0.13

127

1621

± 48

2373

± 21

320.

1524

1.3

6

.010

3

.60.

2858

3.3

0.94

MO

S7.5

.1rim

(lig

ht C

L+da

rk, a

ltere

d co

re)

0.92

270

0.00

2 5

16±

12 6

80±3

6024

0.06

217

.0 0

.710

17

.00.

0834

2.4

0.14

MO

S7.6

.1zo

ned(

strip

ed)

--47

634

10.

7419

525

13±

1627

28±

258

0.18

84 1

.5

12.3

80 1

.70.

4767

0.8

0.45

MO

S7.7

.1ho

mog

CL-

dark

inne

r dom

ain/

roun

ded

(+th

in ri

m)

0.01

361

102

0.29

141

2411

± 37

2523

± 70

40.

1665

4.2

10

.410

4.5

0.45

361.

80.

40M

OS7

.8.1

hom

og C

L-da

rk in

ner d

omai

n/ro

unde

d (+

thin

rim

)--

361

980.

2813

222

84±

2826

20±

9213

0.17

65 5

.5

10.3

50 5

.70.

4252

1.5

0.26

MO

S7.9

.1zo

ned(

strip

ed)

0.05

265

440.

1774

1814

± 90

2461

± 59

260.

1605

3.5

7

.190

6

.70.

3250

5.7

0.85

MO

S7.1

0.1

zone

d(di

stur

bed,

dark

CL)

0.02

554

230

0.43

206

2321

±110

2495

± 7

70.

1638

0.4

9.7

90

5.5

0.43

305.

51.

00M

OS7

.11.

1rim

(CL-

pale

/met

am)

1.57

501

0.01

452

2±

9 4

75±2

70-1

00.

0566

12.0

0.6

5812

.00.

0843

1.7

0.14

MO

S7.1

2.1

zone

d(os

c,C

L-da

rk)

0.10

614

980.

1785

966

± 15

1860

± 17

480.

1137

0.9

2.5

35 1

.90.

1617

1.6

0.87

MO

S7.1

3.1

hom

og,C

L da

rk/m

etam

?/ro

unde

d0.

0034

311

40.

3415

226

81±1

3025

53±

7-5

0.16

960.

412

.050

5.9

0.51

605.

91.

00M

OS7

.14.

1zo

ned(

strip

ed)

0.08

136

470.

3651

2339

± 46

2610

± 37

100.

1754

2.2

10

.580

3.2

0.43

702.

30.

73M

OS7

.15.

1tip

/rim

?,ho

mog

(dar

k C

L)0.

0234

611

40.

3413

123

56±

1925

55±

78

0.16

970.

410

.320

1.1

0.44

111.

00.

92M

os-8

/ 24

50-0

3 M

acan

ga g

rani

teM

OS-

8.1.

1zo

ned(

dark

CL)

0.07

2098

931

0.46

157

540

± 5

484

± 14

-11

0.05

68 0

.60.

684

1.1

0.08

730.

880.

81M

OS-

8.2.

1zo

ned(

dark

CL)

0.22

690

161

0.24

47

488

± 4

525

± 31

70.

0579

1.4

0.

628

1.6

0.07

870.

80.

50M

OS-

8.3.

1zo

ned(

dark

CL)

1.25

4456

2196

0.51

283

454

±40

369

± 75

-23

0.05

40 3

.3

0.54

2 9

.70.

0729

9.1

0.94

MO

S-8.

4.1

zone

d(da

rk C

L)0.

1485

1889

751.

0982

468

7±1

648

0±

14-4

30.

0567

0.6

0.87

9 2

.60.

1125

2.5

0.97

MO

S-8.

5.1

zone

d9.

6754

529

70.

56 3

845

5±1

358

6±3

8022

0.06

0018

.00.

600

18.0

0.07

313.

00.

17M

OS-

8.6.

1zo

ned(

dark

CL)

0.17

1677

623

0.38

120

516

±34

488

± 17

-60.

0569

0.8

0.65

4 7

.00.

0833

6.9

0.99

110


App

endi

x 1.

Con

tinue

d.

Spo

tD

ated

zir

con

dom

ain

% 206 Pb

c

ppm

Upp

mT

h

232 T

h/23

8 Upp

m20

6 Pb*

(1)

206 Pb

/238 U

Age

(1)

207 Pb

/206 Pb

Age

% Dis

-co

r-da

ncy

(1)

207 Pb

*

/206 Pb

*±%

(1)

207 Pb

*

/235 U

±%(1

)20

6 Pb*

/238 U

±%er

rco

rr

MO

S-8.

7.1

zone

d(da

rk C

L)2.

2314

7221

071.

4812

660

1±2

753

1±

77-1

30.

0580

3.5

0.

782

5.9

0.09

774.

70.

80M

OS-

8.8.

1zo

ned(

dark

CL)

0.98

2480

2741

1.14

169

488

±35

381

± 32

-28

0.05

42 1

.4

0.58

8 7

.70.

0786

7.5

0.98

MO

S-8.

9.1

zone

d(da

rk C

L)0.

2471

5758

920.

8547

948

2±

442

9±

42-1

20.

0554

1.9

0.

594

2.1

0.07

770.

90.

41M

OS-

8.10

.1zo

ned(

dark

CL)

0.36

1800

2058

1.18

119

477

± 3

464

± 23

-30.

0563

1.0

0.

596

1.2

0.07

680.

70.

56M

OS-

8.11

.1zo

ned(

dark

CL)

1.51

2290

3419

1.54

113

356

±20

432

± 54

180.

0555

2.4

0.

434

6.2

0.05

675.

70.

92M

OS-

8.12

.1zo

ned(

dark

CL)

1.27

3798

1714

0.47

371

685

±39

388

± 47

-76

0.05

44 2

.1

0.84

2 6

.40.

1122

6.0

0.94

MO

S-8.

13.1

zone

d(da

rk C

L)0.

6839

3719

600.

5130

354

9±2

945

3±

19-2

10.

0560

0.9

0.68

6 5

.70.

0889

5.6

0.99

MO

S-8.

14.1

zone

d(da

rk C

L)0.

1839

9928

820.

7429

052

1±

445

2±

13-1

50.

0560

0.6

0.65

0 1

.00.

0841

0.8

0.82

MO

S-8.

15.1

zone

d(da

rk C

L)0.

8651

6736

660.

7330

642

6±

347

3±

2110

0.05

65 0

.90.

532

1.1

0.06

830.

70.

58M

OS-

12 /

4493

-03

gran

ite, S

inda

Sui

teM

OS-

12.1

.1zo

ned(

dark

CL)

0.05

694

597

0.89

4849

8±1

140

3±

54-2

40.

0548

2.4

0.60

73.

40.

0804

2.4

0.70

MO

S-12

.2.1

zone

d(da

rk C

L)0.

3434

636

71.

1024

498

± 8

425

± 50

-17

0.05

532.

30.

612

2.8

0.08

031.

70.

60M

OS-

12.2

.2co

re/in

ner d

omai

n?(h

omog

)0.

2637

674

92.

0626

505

± 8

425

± 47

-19

0.05

532.

10.

622

2.7

0.08

151.

70.

64M

OS-

12.3

.1rim

/hom

og d

omai

n cu

tting

the

zoni

ng0.

2727

011

30.

4319

509

± 9

463

± 58

-10

0.05

632.

60.

638

3.2

0.08

221.

70.

55M

OS-

12.3

.2zo

ned

0.04

486

416

0.88

3349

4±

854

2±

309

0.05

831.

40.

640

2.2

0.07

961.

70.

78M

OS-

12.4

.1zo

ned(

+sm

all c

ore)

0.22

414

321

0.80

2950

2±

851

7±

403

0.05

771.

80.

645

2.5

0.08

111.

70.

69M

OS-

12.5

.1rim

/hom

og d

omai

n cu

tting

the

zoni

ng0.

0923

214

70.

6516

494

± 9

589

± 44

160.

0596

2.0

0.65

42.

80.

0796

1.8

0.67

MO

S-12

.5.2

zone

d1.

2311

718

11.

60 8

510

±10

295

±160

-73

0.05

227.

00.

593

7.3

0.08

242.

10.

28M

OS-

12.6

.1zo

ned

0.07

159

201

1.31

1151

5±

1062

3±

5617

0.06

062.

60.

694

3.2

0.08

311.

90.

60M

OS-

12.7

.1zo

ned

0.41

329

293

0.92

2350

4±

954

4±

627

0.05

842.

80.

654

3.3

0.08

121.

80.

53M

OS-

12.8

.1zo

ned

0.26

344

181

0.55

2449

2±

954

5±

4410

0.05

842.

00.

639

2.7

0.07

941.

80.

67M

OS-

12.9

.1ne

w ti

p?, w

eakl

y zo

ned,

CL-

pale

0.

0429

617

70.

6220

483

±17

604

± 53

200.

0600

2.4

0.64

44.

40.

0778

3.7

0.83

MO

S-12

.9.2

zone

d in

ner d

omai

n0.

1734

556

71.

7024

506

± 8

517

± 44

20.

0577

2.0

0.64

92.

70.

0817

1.7

0.65

MO

S-12

.10.

1rim

,hom

og0.

5918

212

20.

6913

491

± 9

513

± 99

40.

0576

4.5

0.62

74.

90.

0791

1.8

0.38

MO

S-12

.10.

2zo

ned,

inne

r dom

ain

0.68

352

397

1.16

2550

0±

833

1±

69-5

10.

0530

3.1

0.59

03.

50.

0807

1.7

0.49

MO

S-15

/ 42

41-0

3 gr

anite

, Cas

saca

tiza

Suite

MO

S-15

.1.1

zone

d0.

1163

877

91.

26 9

810

60±

1611

26±1

46

0.07

720.

71.

903

1.8

0.17

88 1

.70.

92M

OS-

15.2

.1zo

ned

0.11

226

116

0.53

36

1102

± 18

1127

±24

20.

0772

1.2

1.98

5 2

.20.

1864

1.8

0.83

MO

S-15

.3.1

zone

d(da

rk C

L)0.

0249

5163

80.

1386

711

96±

1911

17±

6-7

0.07

680.

32.

159

1.7

0.20

38 1

.70.

98M

OS-

15.3

.2rim

/tip,

CL-

pale

0.00

559

450.

08 8

910

91±

1711

48±3

25

0.07

801.

61.

984

2.4

0.18

45 1

.70.

73M

OS-

15.4

.1zo

ned

0.07

590

329

0.58

96

1120

± 17

1130

±15

10.

0774

0.7

2.02

4 1

.80.

1898

1.7

0.91

MO

S-15

.5.1

zone

d0.

2544

943

31.

00 7

811

86±

3810

99±1

9-8

0.07

621.

02.

121

3.6

0.20

19 3

.50.

96M

OS-

15.6

.1zo

ned

0.42

1371

494

0.37

188

952

± 44

1080

±15

120.

0754

0.7

1.65

4 5

.00.

1591

5.0

0.99

MO

S-15

.6.2

zone

d(C

L-pa

le)

0.10

1254

495

0.41

209

1143

±120

1162

±28

20.

0786

1.4

2.10

011

.00.

1940

11.0

0.99

MO

S-15

.7.1

zone

d0.

1558

955

70.

9810

211

87±1

1010

66±4

3-1

10.

0749

2.1

2.09

010

.00.

2020

9.7

0.98

MO

S-15

.8.1

zone

d0.

3419

681

0.43

32

1128

± 18

1097

±34

-30.

0761

1.7

2.00

5 2

.50.

1912

1.8

0.71

MO

S-15

.9.1

core

/inne

r dom

ain?

(CL-

pale

,hom

og)

0.26

200

236

1.22

33

1120

± 18

1060

±37

-60.

0747

1.8

1.95

4 2

.60.

1898

1.8

0.70

MO

S-15

.9.2

rim, d

ark

CL

0.11

1237

137

0.11

198

1100

± 21

1125

±14

20.

0772

0.7

1.98

0 2

.20.

1861

2.1

0.95

MO

S-15

.10.

1zo

ned

0.51

1418

270

0.20

208

1010

± 41

1022

±43

10.

0733

2.1

1.71

3 4

.80.

1695

4.4

0.90

MO

S-15

.11.

1zo

ned

0.16

1117

378

0.35

202

1231

±130

1140

±29

-80.

0777

1.5

2.25

012

.00.

2100

12.0

0.99

111


App

endi

x 1.

Con

tinue

d.

MO

S-19

.18.

1 zo

ned

(hit

partl

y on

CL-

dark

cen

ter d

omai

n?)

2.13

699

276

0.41

8179

8

±10

84

0±6

85

0.06

71

3.3

1.21

9 3.

5 0.

1318

1.

4 0.

39

Spo

tD

ated

zir

con

dom

ain

% 206 Pb

c

ppm

Upp

mT

h

232 T

h/23

8 Upp

m20

6 Pb*

(1)

206 Pb

/238 U

Age

(1)

207 Pb

/206 Pb

Age

% Dis

-co

r-da

ncy

(1)

207 Pb

*

/206 Pb

*±%

(1)

207 Pb

*

/235 U

±%(1

)20

6 Pb*

/238 U

±%er

rco

rr

MO

S-16

/ 13

016-

03 g

rani

te g

neis

s, M

atun

da S

uite

MO

S-16

.1.1

rim, d

ark

CL,

hom

og1.

7016

7923

0.01

108

457

±41

594

± 84

230.

0597

3.9

0.60

510

.00.

0734

9.3

0.92

MO

S-16

.1.2

MO

S-16

.2.1

core

, pal

e C

L, z

oned

hom

og,m

ediu

m C

L/m

etam

? /ro

unde

d(+t

hin

dark

CL

0.12

--99 33

686 19

60.

900.

60 1

1 3

780

678

4±

8±

683

882

2±

59±

294 5

0.06

700.

0665

2.8

1.4

1.23

01.

186

3.0

1

.6

0.13

310.

1294

1.0

0.8

0.34

0.49

rim)

MO

S-16

.3.1

rim,d

ark

CL(

+met

amic

t cor

e?)

0.78

574

70.

01 4

151

2±

752

8±

463

0.05

802.

10.

660

2.5

0.

0826

1.3

0.54

MO

S-16

.4.1

MO

S-16

.4.2

met

amic

t mai

n do

mai

n (+

thin

CL-

pale

rim

)zo

ned,

smal

l gra

in in

side

a m

etam

ict g

rain

0.

430.

3599

836

429 29

50.

030.

84 8

0 3

957

074

9±1

5±

559

174

9±

27±

344 0

0.05

970.

0642

1.2

1.6

0.76

01.

090

3.0

1

.8

0.09

240.

1231

2.8

0.7

0.91

0.42

MO

S-16

.5.1

hom

og,d

ark

CL,

roun

ded

(+th

in C

L-pa

le ri

m)

0.02

1770

120.

0113

053

1±

348

2±

43-1

00.

0568

2.0

0.67

1 2

.1

0.08

580.

70.

32M

OS-

16.6

.1co

re,z

oned

,pal

e C

L0.

5911

710

30.

91 1

377

3±

781

3±

755

0.06

623.

61.

163

3.7

0.

1274

1.0

0.26

MO

S-16

.6.2

rim,h

omog

,dar

k C

l0.

3918

8414

0.01

139

528

± 3

555

± 19

50.

0587

0.9

0.69

1 1

.0

0.08

540.

60.

57M

OS-

16.7

.1zo

ned/

dist

urbe

d(+t

hin

rim)

2.27

506

386

0.79

51

703

± 5

733

± 71

40.

0637

3.4

1.01

3 3

.4

0.11

530.

70.

21M

OS-

16.8

.1zo

ned,

pale

CL,

fres

h cr

ysta

l0.

0026

121

90.

87 2

977

1±

683

0±

267

0.06

681.

21.

169

1.5

0.

1271

0.9

0.57

MO

S-16

.9.1

zone

d,da

rk C

L0.

1314

0863

10.

4614

673

6±

576

3±

144

0.06

460.

71.

077

1.0

0.12

090.

70.

72M

OS-

16.1

0.1

zone

d,fr

esh

grai

n0.

5082

586

61.

08 8

169

6±

474

7±

257

0.06

421.

21.

009

1.3

0.

1141

0.7

0.49

MO

S-16

.11.

1zo

ned

tip d

omai

n (z

oned

,repl

aced

inne

r dom

ain)

0.13

696

40.

01 5

152

2±

356

4±

267

0.05

891.

20.

685

1.4

0.

0844

0.7

0.48

MO

S-16

.12.

1 co

re?/

zone

d do

mai

n--

48

150

41.

08 4

870

7±

691

2±

6722

0.

0694

3.

3 1.

110

3.4

0.

1160

0.

90.

26M

os-1

9 / 2

638-

04 a

plite

gra

nite

, Gur

o Su

iteM

OS-

19.1

.1zo

ned,

CL-

pale

inne

r dom

ain

0.11

486

311

0.66

6085

8±4

804

±40

-60.

0659

1.9

1.29

42.

00.

1424

0.5

0.26

MO

S-19

.1.2

quite

hom

ogen

eous

, CL-

dark

rim

0.11

2071

313

0.16

245

832

±283

4±1

30

0.06

690.

61.

270

0.7

0.13

770.

30.

39M

OS-

19.2

.1qu

ite h

omog

eneo

us, C

L-pa

le ri

m1.

1858

116

20.

2969

824

±481

0±5

4-2

0.06

612.

61.

243

2.7

0.13

630.

60.

21M

OS-

19.3

.1qu

ite h

omog

eneo

us, C

L-pa

le ri

m0.

3864

513

50.

2279

857

±486

3±3

51

0.06

781.

71.

330

1.7

0.14

220.

50.

27M

OS-

19.3

.2C

L-da

rk a

nd sp

otty

inne

r dom

ain

0.04

2475

625

0.26

290

825

±283

6±1

21

0.06

690.

61.

259

0.6

0.13

640.

30.

46M

OS-

19.4

.1zo

ned,

CL-

dark

0.44

522

354

0.70

6182

5±4

834

±37

10.

0669

1.8

1.25

81.

80.

1364

0.5

0.28

MO

S-19

.5.1

zone

d, C

L-da

rk0.

2067

548

20.

7482

852

±486

9±2

42

0.06

801.

21.

325

1.3

0.14

120.

40.

35M

OS-

19.6

.1zo

ned,

CL-

brig

ht0.

7028

116

70.

6133

827

±579

8±6

3-4

0.06

573.

01.

241

3.1

0.13

690.

70.

22M

OS-

19.7

.1C

L-pa

le re

plac

ing

phas

e2.

6848

012

20.

2656

796

±575

0±9

6-6

0.06

434.

51.

164

4.6

0.13

140.

70.

15M

OS-

19.8

.1qu

ite h

omog

eneo

us, C

L-m

ediu

m in

ner d

omai

n0.

5299

16

0.01

7251

8±2

528

±42

20.

058

1.9

0.66

92.

00.

0837

0.5

0.24

MO

S-19

.9.1

quite

hom

ogen

eous

, Cl-d

ark

core

dom

ain

0.07

651

300.

0546

513

± 3

515

±30

10.

0576

1.4

0.65

81.

50.

0828

0.6

0.38

MO

S-19

.9.2

quite

hom

ogen

eous

, CL-

dark

rim

0.08

662

419

0.65

8185

4±

484

3±2

4-1

0.06

721.

11.

312

1.2

0.14

160.

40.

36M

OS-

19.1

0.1

zone

d, C

L-da

rk0.

1364

649

60.

7978

848

± 4

863

±23

20.

0678

1.1

1.31

41.

20.

1406

0.5

0.41

MO

S-19

.11.

1w

eakl

y zo

ned,

CL-

dark

0.16

1079

140.

0180

530

± 2

485

±30

-80.

0568

1.4

0.67

11.

40.

0857

0.4

0.27

MO

S-19

.12.

1zo

ned,

CL-

dark

0.01

782

363

0.48

9181

4±

487

2±1

77

0.06

810.

81.

265

0.9

0.13

470.

50.

49M

OS-

19.1

3.1

zone

d, C

L-m

ediu

m0.

1650

338

40.

7962

857

± 5

849

±32

-10.

0674

1.5

1.32

01.

60.

1421

0.6

0.35

MO

S-19

.14.

1zo

ned,

CL-

med

ium

0.18

915

345

0.39

107

822

± 3

879

±21

70.

0684

1.0

1.28

11.

10.

1360

0.4

0.40

MO

S-19

.15.

1zo

ned/

spot

ty, C

L-da

rk0.

0313

1530

0.02

9350

9±

250

7±2

10

0.05

741.

00.

650

1.0

0.08

210.

40.

39M

OS-

19.1

6.1

zone

d, C

L-da

rk0.

5113

7711

00.

0810

856

1±

261

8±4

910

0.06

042.

30.

757

2.3

0.09

090.

40.

18M

OS-

19.1

7.1

zone

d, C

L-da

rk0.

1397

952

90.

5611

381

3±

390

3±1

911

0.06

920.

91.

281

1.0

0.13

430.

40.

37

112


App

endi

x 1.

Con

tinue

d.

MO

S-21

.13.

1zo

ned,

Cl-m

ediu

m0.

0525

021

80.

9010

726

09±1

226

54+9

20.

1801

0.6

12.3

860.

80.

4988

0.6

0.72

Spo

tD

ated

zir

con

dom

ain

% 206 Pb

c

ppm

Upp

mT

h

232 T

h/23

8 Upp

m20

6 Pb*

(1)

206 Pb

/238 U

Age

(1)

207 Pb

/206 Pb

Age

% Dis

-co

r-

(1)

207 Pb

*

/206 Pb

*±%

(1)

207 Pb

*

/235 U

±%(1

)20

6 Pb*

/238 U

±%er

rco

rrda

ncy

Mos

-20

/ 294

3-04

gar

net-

silli

man

ite g

neis

s, R

ushi

nga

Gro

upM

OS-

20.1

.1C

L-br

ight

rim

2.09

120

60.

059

506

± 8

490

+247

-30.

0570

11.2

0.64

111

.30.

0816

1.7

0.15

MO

S-20

.1.2

zone

d m

ain

dom

ain

(+C

L-br

ight

rim

)0.

1327

446

0.18

8419

59±1

126

73+1

236

0.18

220.

78.

922

1.0

0.35

520.

70.

68M

OS-

20.2

.1C

L-da

rk, s

moo

thly

zon

ed (+

thin

CL-

brig

ht ri

m)

1.65

845

230.

0369

576

±395

1+6

565

0.07

083.

20.

911

3.2

0.09

340.

50.

16M

OS-

20.3

.1C

L-da

rk, s

moo

thly

zon

ed (

thin

CL-

brig

ht ri

m)

0.33

485

140.

0335

521

±352

8+8

31

0.05

793.

80.

673

3.8

0.08

430.

60.

17M

OS-

20.4

.1C

L-br

ight

rim

on

zirc

on 8

6.71

567

0.12

447

5±1

661

9+

795

300.

0604

36.8

0.63

837

.00.

0765

3.4

0.09

MO

S-20

.4.2

core

(CL-

dark

and

brig

ht ri

ms a

roun

d it)

0.47

293

610.

2276

1691

±923

67+1

640

0.15

190.

96.

281

1.1

0.30

000.

60.

54M

OS-

20.5

.1C

L-br

ight

rim

on

zirc

on 8

1.17

127

70.

059

497

±763

1+2

4627

0.06

0811

.40.

671

11.5

0.08

011.

50.

13M

OS-

20.6

.1zo

ned,

CL-

dark

0.36

656

820.

1384

891

±415

53+2

374

0.09

621.

21.

967

1.3

0.14

820.

50.

36M

OS-

20.7

.1C

L-br

ight

rim

on

zirc

on 8

21.0

032

50.

163

500

±28

-263

6+

0-6

280.

0806

5.9

MO

S-20

.8.1

cent

er/c

ore?

, CL-

dark

1.87

225

490.

2341

1211

±11

2244

+38

850.

1414

2.2

4.02

92.

40.

2067

1.0

0.41

MO

S-20

.9.1

CL-

dark

dom

ain

(+co

re+C

L-br

ight

rim

)1.

9212

1830

0.03

8449

1±2

351

+87

-29

0.05

353.

90.

584

3.9

0.07

920.

50.

12M

OS-

20.9

.2co

re, C

L-m

ediu

m0.

4837

981

0.22

6812

20±7

1810

+30

480.

1106

1.6

3.17

91.

70.

2084

0.6

0.34

MO

S-20

.10.

1sm

ooth

ly z

oned

, CL-

dark

(+m

etam

ict c

ore)

0.91

501

90.

0236

515

±452

0+1

101

0.05

775.

00.

661

5.1

0.08

310.

70.

15M

OS-

20.1

1.1

cent

er, z

oned

CL-

pale

dom

ain

0.29

308

137

0.46

8417

76±1

019

08+1

97

0.11

681.

05.

106

1.2

0.31

710.

70.

53M

OS-

20.1

2.1

zone

d co

re (+

CL-

brig

ht ri

m)

0.03

467

920.

2012

817

87±7

2426

+12

360.

1572

0.7

6.92

60.

80.

3195

0.5

0.56

MO

S-20

.13.

1zo

ned

core

(+C

L-br

ight

rim

)0.

2837

662

0.17

6211

22±6

2149

+21

910.

1338

1.2

3.50

81.

30.

1901

0.6

0.42

MO

S-20

.14.

1co

re, C

L-m

ediu

m1.

6425

810

50.

4269

1720

±11

2449

+30

420.

1593

1.8

6.71

91.

90.

3058

0.7

0.39

Mos

-21

/ 151

9-04

Fud

eze

orth

ogne

iss,

Mud

zi M

etam

orph

ic C

ompl

exM

OS-

21.1

.1zo

ned

core

0.

2660

718

60.

3224

925

11±8

3048

+621

0.22

940.

415

.061

0.5

0.47

620.

40.

72M

OS-

21.1

.2zo

ned,

CL-

dark

0.19

747

115

0.16

251

2128

±825

09+8

180.

1652

0.5

8.90

50.

60.

3910

0.4

0.68

MO

S-21

.2.1

zone

d, C

L-da

rk0.

1446

743

0.10

188

2474

±10

2599

+85

0.17

430.

511

.239

0.7

0.46

780.

50.

72M

OS-

21.3

.1zo

ned,

CL-

dark

0.71

672

115

0.18

252

2324

±925

98+9

120.

1742

0.6

10.4

240.

70.

4340

0.4

0.62

MO

S-21

.4.1

zone

d, C

L-da

rk0.

2696

877

0.08

255

1721

±623

61+8

370.

1513

0.5

6.38

40.

60.

3060

0.4

0.64

MO

S-21

.5.1

zone

d, C

L-m

ediu

m, t

ip

0.14

314

102

0.34

121

2389

±11

2595

+10

90.

1739

0.6

10.7

540.

80.

4486

0.6

0.68

MO

S-21

.5.2

zone

d, C

L-da

rk, m

iddl

e 0.

2169

969

0.10

179

1677

±76

2073

+133

240.

1282

7.6

5.25

19.

20.

2972

5.2

0.57

MO

S-21

.5.3

zone

d, C

L-m

ediu

m,c

ente

r 0.

0145

937

30.

8421

427

88±1

228

66+1

293

0.20

507.

915

.291

7.9

0.54

100.

50.

07M

OS-

21.6

.1zo

ned,

CL-

med

ium

-0

.01

211

720.

3590

2596

±16

2489

+75

-40.

1632

4.4

11.1

594.

50.

4958

0.8

0.17

MO

S-21

.7.1

CL-

brig

ht ri

m31

.01

303

0.12

576

0±6

220

22+

1606

166

0.12

4590

.62.

148

91.0

0.12

518.

70.

10M

OS-

21.8

.1zo

ned,

Cl-m

ediu

m

--55

033

70.

6324

627

02±9

2756

+86

20.

1916

5.3

13.7

505.

30.

5205

0.4

0.08

MO

S-21

.9.1

zone

d, C

l-med

ium

0.16

208

600.

3088

2569

±27

2589

+21

10.

1732

1.2

11.6

931.

80.

4896

1.3

0.71

MO

S-21

.10.

1zo

ned,

Cl-m

ediu

m

0.32

180

840.

4972

2463

±14

2597

+13

50.

1740

0.8

11.1

641.

00.

4653

0.7

0.65

MO

S-21

.11.

1zo

ned,

Cl-m

ediu

m

0.36

491

920.

1912

816

98±8

2365

+12

390.

1517

0.7

6.30

60.

90.

3014

0.5

0.61

MO

S-21

.12.

1zo

ned,

Cl-m

ediu

m0.

0932

819

50.

6114

326

50±1

327

14+1

22

0.18

670.

713

.091

0.9

0.50

840.

60.

62

113


App

endi

x 1.

Con

tinue

d.

MO

S-28

.7.1

quite

hom

ogen

eous

cen

tre d

omai

n0.

1718

512

10.

6874

2475

+20

2495

+15

10.

1638

0.9

10.5

711.

30.

4681

1.0

0.75

Spo

tD

ated

zir

con

dom

ain

% 206 Pb

c

ppm

Upp

mT

h

232 T

h/23

8 Upp

m20

6 Pb*

(1)

206 Pb

/238 U

Age

(1)

207 Pb

/206 Pb

Age

% Dis

-co

r-

(1)

207 Pb

*

/206 Pb

*±%

(1)

207 Pb

*

/235 U

±%(1

)20

6 Pb*

/238 U

±%er

rco

rrda

ncy

Mos

-23

/ 136

25-0

4 to

nalit

e, M

avon

de C

ompl

exM

OS-

23.1

.1zo

ned,

CL-

dark

0.11

425

292

0.71

204

2861

±16

2909

+92

0.21

040.

516

.206

0.9

0.55

860.

70.

79M

OS-

23.2

.1C

L-m

ediu

m d

ark,

wea

kly

zone

d co

re/c

entre

dom

ain

0.16

136

640.

4968

2934

±39

2911

+15

-10.

2108

0.9

16.7

471.

90.

5763

1.6

0.87

MO

S-23

.3.1

zone

d, C

L-da

rk0.

0522

386

0.40

110

2930

±19

2909

+9-1

0.21

050.

616

.702

1.0

0.57

540.

80.

81M

OS-

23.4

.1zo

ned,

CL-

dark

0.08

384

203

0.55

184

2862

±16

2900

+71

0.20

930.

416

.130

0.8

0.55

890.

70.

84M

OS-

23.5

.1zo

ned,

CL-

dark

0.56

426

187

0.45

199

2793

±18

2921

+11

50.

2121

0.7

15.8

551.

00.

5423

0.8

0.77

MO

S-23

.6.1

zone

d, C

L-da

rk0.

2329

314

50.

5113

126

94±1

628

98+9

80.

2090

0.6

14.9

490.

90.

5188

0.7

0.80

MO

S-23

.7.1

zone

d, C

L-da

rk0.

2525

913

70.

5511

827

36±1

928

73+1

05

0.20

580.

615

.008

1.0

0.52

880.

90.

81M

OS-

23.8

.1C

L-da

rk, q

uite

hom

ogen

eous

cor

e0.

2656

530

50.

5621

423

51±1

327

29+8

160.

1884

0.5

11.4

360.

80.

4402

0.7

0.82

MO

S-23

.8.2

CL-

med

ium

dar

k, w

eakl

y zo

ned

tip0.

2320

679

0.40

9728

21±1

928

83+1

12

0.20

710.

715

.671

1.0

0.54

890.

80.

78M

OS-

23.9

.1zo

ned,

CL-

dark

0.19

254

147

0.60

121

2838

±19

2901

+92

0.20

940.

615

.969

1.0

0.55

320.

80.

82M

OS-

23.1

0.1

zone

d, C

L-da

rk0.

1035

214

20.

4216

828

47±1

628

88+8

10.

2077

0.5

15.9

020.

90.

5552

0.7

0.83

MO

S-23

.10.

2C

l-dar

k re

plac

ing

hom

ogen

eous

pha

se0.

1589

634

0.04

236

1724

±924

63+8

430.

1607

0.5

6.79

40.

80.

3066

0.6

0.79

Mos

-26

/ 101

1-02

gar

net g

neis

s, G

aire

zi G

roup

MO

S-26

.1.1

hom

ogen

eous

, CL-

dark

0.12

270

207

0.79

108

2460

+16

2574

+11

50.

1717

0.7

10.9

981.

00.

4646

0.8

0.75

MO

S-26

.2.1

zone

d, d

ark

and

pale

strip

es0.

1519

594

0.50

7122

70+1

621

31+1

6-6

0.13

250.

97.

708

1.3

0.42

210.

90.

67M

OS-

26.3

.1zo

ned,

CL-

med

ium

dar

k--

279

580.

2193

2109

+14

2063

+14

-20.

1275

0.8

6.80

01.

10.

3869

0.8

0.71

MO

S-26

.4.1

zone

d, C

L-da

rk0.

1150

956

0.11

153

1930

+12

2035

+12

50.

1254

0.7

6.03

71.

00.

3490

0.7

0.74

MO

S-26

.5.1

zone

d, d

ark

and

pale

strip

es0.

3411

241

0.38

3519

94+1

820

48+2

43

0.12

631.

46.

313

1.7

0.36

241.

00.

60M

OS-

26.6

.1zo

ned,

Cl-m

ediu

m d

ark

0.11

293

116

0.41

9320

27+1

320

61+1

62

0.12

730.

96.

485

1.2

0.36

940.

80.

64M

OS-

26.7

.1qu

ite h

omog

eneo

us, C

L-pa

le, r

ound

0.18

7750

0.67

2420

21+2

120

44+3

11

0.12

611.

76.

400

2.1

0.36

821.

20.

57M

OS-

26.7

.2ho

mog

eneo

us, C

L-da

rk, r

ound

0.11

328

302

0.95

102

1994

+13

2015

+14

10.

1240

0.8

6.20

11.

10.

3625

0.8

0.71

MO

S-26

.8.1

wea

kly

zone

d, C

L-br

ight

, rou

nd (m

etam

orph

ic?)

0.61

9422

92.

5123

1602

+18

1885

+54

180.

1153

3.0

4.48

63.

30.

2821

1.3

0.40

MO

S-26

.9.1

zone

d, C

L-da

rk, r

ound

0.04

335

198

0.61

153

2755

+17

3063

+711

0.23

160.

417

.031

0.9

0.53

330.

80.

86M

OS-

26.1

0.1

zone

d, C

L-m

ediu

m0.

1121

610

90.

5269

2024

+14

2049

+19

10.

1264

1.1

6.42

91.

40.

3688

0.8

0.61

MO

S-26

.11.

1zo

ned,

CL-

med

ium

dar

k0.

1250

019

70.

4114

018

15+1

119

81+1

29

0.12

170.

75.

453

1.0

0.32

510.

70.

73M

OS-

26.1

2.1

zone

d, C

L-da

rk0.

1544

824

40.

5613

419

29+1

120

24+1

25

0.12

460.

75.

995

1.0

0.34

890.

70.

70M

OS-

26.1

3.1

wea

kly

zone

d, C

L-pa

le0.

3713

352

0.40

4119

66+1

720

65+2

95

0.12

761.

76.

270

1.9

0.35

651.

00.

51M

OS-

26.1

4.1

quite

hom

ogen

eous

, CL-

pale

(?zo

ned

rim)

0.12

210

790.

3988

2571

+19

2636

+12

30.

1781

0.7

12.0

361.

20.

4901

0.9

0.79

MO

S-26

.15.

1zo

ned,

dar

k an

d pa

le st

ripes

0.12

194

157

0.84

8326

11+1

826

98+1

33

0.18

490.

812

.732

1.1

0.49

930.

90.

75M

OS-

26.1

6.1

zone

d, C

L-m

ediu

m d

ark

0.21

169

980.

6054

2047

+16

2051

+22

00.

1266

1.2

6.52

11.

50.

3737

0.9

0.60

Mos

-28

/ 193

13-0

4 gr

anite

, Bár

uè C

ompl

ex

MO

S-28

.1.1

zone

d, C

L-da

rk0.

1339

028

00.

7414

022

45+1

424

10+1

07

0.15

580.

68.

945

1.0

0.41

650.

70.

78M

OS-

28.2

.1zo

ned,

CL-

dark

0.27

348

327

0.97

5711

20+8

1162

+34

40.

0786

1.7

2.05

71.

90.

1898

0.8

0.42

MO

S-28

.3.1

zone

d ce

nter

dom

ain,

CL-

dark

0.06

386

256

0.69

128

2101

+36

2049

+12

-20.

1264

0.7

6.71

42.

10.

3852

2.0

0.95

MO

S-28

.4.1

quite

hom

ogen

eous

, CL-

brig

h0.

4314

352.

583

1269

+34

2090

+89

650.

1294

5.0

3.88

45.

80.

2176

2.9

0.50

MO

S-28

.5.1

zone

d, C

L-m

ediu

m0.

4536

038

31.

1057

1088

+810

90+4

00

0.07

582.

01.

921

2.2

0.18

390.

80.

38M

OS-

28.6

.1zo

ned,

CL-

dark

1.14

687

479

0.72

7677

0+5

1073

+48

390.

0752

2.4

1.31

42.

50.

1268

0.7

0.29

114


App

endi

x 1.

Con

tinue

d.

MO

S-33

.10.

1zo

ned,

CL-

med

ium

0.00

185

660.

3733

1216

±18

1251

± 69

30.

0822

3.5

2.35

33.

90.

2076

1.7

0.43

Spo

tD

ated

zir

con

dom

ain

% 206 Pb

c

ppm

Upp

mT

h

232 T

h/23

8 Upp

m20

6 Pb*

(1)

206 Pb

/238 U

(1)

207 Pb

/206 Pb

% Dis

-co

r-

(1)

207 Pb

*

206

*±%

(1)

207 Pb

*

235

±%(1

)20

6 Pb*

238

±%er

rco

rrA

geA

geda

ncy

/Pb

/U

/U

MO

S-28

.8.1

zone

d, C

L-m

ediu

m0.

0534

444

51.

3457

1130

+811

80+3

34

0.07

931.

72.

095

1.9

0.19

160.

80.

42M

OS-

28.9

.1zo

ned,

CL-

brig

ht1.

6895

124

1.34

1499

7+1

412

21+1

3322

0.08

106.

81.

867

6.9

0.16

721.

50.

22M

OS-

28.1

0.1

zone

d, C

L-da

rk1.

4763

419

20.

3190

976

+612

76+4

231

0.08

332.

21.

877

2.3

0.16

350.

70.

30M

OS-

28.1

1.1

zone

d, C

L-da

rk0.

9218

319

71.

1130

1123

+13

1080

+82

-40.

0754

4.1

1.97

94.

30.

1903

1.2

0.29

MO

S-28

.12.

1zo

ned,

CL-

dark

0.09

246

152

0.64

7118

79+1

518

30+1

7-3

0.11

191.

05.

219

1.3

0.33

840.

90.

68M

OS-

28.1

3.1

wea

kly

zone

d, C

L-br

ight

0.01

269

188

0.72

8520

17+1

420

27+1

40

0.12

490.

86.

324

1.1

0.36

730.

80.

71M

OS-

28.1

4.1

zone

d, C

L-da

rk0.

5722

023

11.

0937

1139

+11

1133

+57

00.

0775

2.9

2.06

43.

00.

1932

1.0

0.34

Mos

-29

/ 192

90-0

4 In

chap

a gr

anod

iori

te, B

áruè

Com

plex

MO

S-29

.1.1

zone

d, C

L-m

ediu

m, l

ong

(+C

L-da

rk ri

m)

0.26

630

741

1.22

8897

1±

410

87±

2812

0.07

57 1

.41.

697

1.4

0.16

260.

50.

32M

OS-

29.1

.2ho

mog

eneo

us C

L-da

rk ri

m4.

3822

2016

40.

0825

276

8±

3 9

02±

8317

0.06

914.

01.

205

4.0

0.12

650.

40.

11M

OS-

29.2

.1zo

ned,

CL-

pale

, lon

g (+

CL-

dark

rim

)6.

1527

097

0.37

1741

8±

5 7

62±2

3082

0.06

4611

.00.

597

11.0

0.06

701.

20.

11M

OS-

29.3

.1zo

ned,

CL-

pale

, lon

g (+

CL-

dark

rim

)0.

6612

499

0.82

1910

65±

911

66±

659

0.07

87 3

.31.

950

3.4

0.17

961.

00.

28M

OS-

29.4

.1zo

ned,

CL-

pale

, lon

g (+

CL-

dark

rim

)0.

3417

470

0.42

2710

63±

811

23±

676

0.07

71 3

.41.

905

3.5

0.17

920.

80.

24M

OS-

29.5

.1zo

ned,

CL-

med

ium

, lon

g (+

CL-

dark

rim

)0.

2474

692

81.

2910

810

06±

410

76±

227

0.07

528

1.1

1.75

2 1

.20.

1688

0.4

0.35

MO

S-29

.5.2

hom

ogen

eous

CL-

dark

rim

0.65

1792

710.

0416

765

9±

2 9

02±

2837

0.06

912

1.4

1.02

6 1

.40.

1076

0.4

0.26

MO

S-29

.6.1

zone

d, C

L-m

ediu

m, l

ong

(+C

L-da

rk ri

m)

0.15

567

475

0.86

8910

83±

510

70±

22-1

0.07

504

1.1

1.89

2 1

.20.

1829

0.5

0.39

MO

S-29

.7.1

zone

d, C

L-pa

le, s

hort

(+C

L-da

rk ri

m)

2.38

160

165

1.07

2611

09±

1011

04±1

100

0.07

63 5

.61.

980

5.6

0.18

771.

00.

17M

OS-

29.8

.1zo

ned,

CL-

pale

, sho

rt (+

CL-

dark

rim

)1.

0511

111

51.

0718

1081

±10

1017

± 77

-60.

0731

3.8

1.84

0 3

.90.

1826

1.0

0.26

MO

S-29

.9.1

zone

d, C

L-m

ediu

m d

ark,

shor

t0.

0849

812

40.

26 7

810

79±

510

88±

221

0.07

573

1.1

1.90

2 1

.20.

1822

0.5

0.41

MO

S-29

.10.

1zo

ned,

CL-

pale

, sho

rt (+

CL-

dark

rim

)0.

6615

515

81.

0525

1099

± 9

1037

± 65

-60.

0738

3.2

1.89

2 3

.40.

1858

0.9

0.27

MO

S-29

.11.

1zo

ned,

CL-

med

ium

, sho

rt (+

CL-

dark

rim

)0.

3929

218

20.

65 4

610

81±

710

76±

410

0.07

53 2

.11.

894

2.2

0.18

250.

70.

30M

OS-

29.1

2.1

zone

d, C

L-pa

le, s

hort

(+C

L-da

rk ri

m)

0.96

7911

01.

44 1

210

42±1

211

37±

979

0.07

76 4

.91.

877

50.

1754

1.3

0.25

MO

S-29

.13.

1zo

ned,

CL-

pale

, sho

rt (+

CL-

dark

rim

)1.

5891

127

1.45

1410

41±1

1 9

99±1

00-4

0.07

25 5

.11.

751

5.2

0.17

521.

10.

21M

OS-

29.1

3.2

hom

ogen

eous

CL-

dark

rim

3.86

3664

640.

0219

337

0±

2 9

92±

6916

80.

0722

3.4

0.58

8 3

.40.

0591

0.4

0.11

MO

S-29

.14.

1 zo

ned,

CL-

med

ium

, lon

g (+

CL-

dark

rim

)0.

4172

544

50.

63 7

0

684

± 3

1101

± 32

61

0.07

62

1.6

1.17

7 1

.70.

1120

0.5

0.30

MO

S-33

/ 41

58-0

3 m

etas

ands

tone

, Zám

buè

Supe

rgro

upM

OS-

33.1

.1ha

zy z

onin

g, y

oung

er, C

L-da

rk d

omai

n9.

6669

518

0.03

117.

010

51±1

410

66±

283

10.

0749

14.1

1.82

914

.20.

1771

1.5

0.11

MO

S-33

.1.2

zone

d, C

L-br

ight

dom

ain

5.43

199

119

0.62

6018

61±3

318

80±

168

10.

1150

9.3

5.30

59.

60.

3346

2.0

0.21

MO

S-33

.2.1

zone

d, C

L-da

rk (+

dark

thin

rim

)9.

8896

952

80.

5612

682

7±1

286

1±

333

40.

0678

16.0

1.27

916

.10.

1369

1.5

0.09

MO

S-33

.3.1

zone

d, C

l-brig

ht, r

ound

ed c

ore

(+th

in C

l-dar

k rim

)6.

8016

718

21.

1335

1310

±27

1324

± 31

81

0.08

5416

.42.

652

16.6

0.22

542.

30.

14

MO

S-33

.4.1

Cl-b

right

, rou

nded

cor

e1.

4526

585

0.33

9221

55±2

321

54±

610

0.13

423.

57.

348

3.7

0.39

701.

30.

35M

OS-

33.5

.1ho

mog

eneo

us, C

L-da

rk ri

m (+

roun

ded

core

)0.

4590

211

60.

1315

711

85±8

1166

± 49

-20.

0788

2.4

2.19

12.

60.

2017

0.8

0.30

MO

S-33

.6.1

quite

hom

ogen

eou,

CL-

dark

rim

41.5

917

0840

50.

2425

061

1±2

863

5±

1446

40.

0609

67.2

0.83

567

.30.

0995

4.8

0.07

MO

S-33

.6.2

zone

d, C

L-m

ediu

m ro

unde

d co

re0.

1318

221

31.

2181

2683

±36

2689

± 27

00.

1839

1.6

13.0

902.

30.

5161

1.6

0.71

MO

S-33

.7.1

zone

d, C

L-da

rk, e

uhed

ral

3.53

1017

860.

0916

710

89±1

011

10±

128

20.

0766

6.4

1.94

36.

50.

1841

1.0

0.16

MO

S-33

.8.1

CL-

dark

rim

21.9

126

8810

30.

0417

637

3±9

385

± 81

73

0.05

4336

.40.

446

36.4

0.05

952.

40.

06M

OS-

33.8

.2zo

ned,

CL-

brig

ht c

ore

0.00

5967

1.16

1920

51±4

520

58±

670

0.12

713.

86.

567

4.6

0.37

472.

60.

56M

OS-

33.9

.1zo

ned,

CL-

dark

euh

edra

l gra

in0.

3387

012

70.

1515

011

77±9

1147

± 47

-30.

0780

2.3

2.15

42.

50.

2003

0.8

0.33

115


App

endi

x 1.

Con

tinue

d.

for M

os-3

3-M

os35

.

Spo

tD

ated

zir

con

dom

ain

% 206 Pb

c

ppm

Upp

mT

h

232 T

h/23

8 Upp

m20

6 Pb*

(1)

206 Pb

/238 U

(1)

207 Pb

/206 Pb

% Dis

-co

r-

(1)

207 Pb

*±%

(1)

207 Pb

*±%

(1)

206 Pb

*±%

err

corr

Age

Age

danc

y/20

6 Pb*

/235 U

/238 U

MO

S-33

.11.

1zo

ned,

CL-

med

ium

(+da

rk ri

m; m

argi

nal p

hase

?)13

.79

571

126

0.23

100

1041

±20

1071

± 42

63

0.07

5121

.21.

814

21.3

0.17

522.

10.

10M

OS-

33.1

2.1

hom

ogen

eous

, CL-

dark

rim

(+ro

unde

d co

re)

69.0

180

6732

330.

4110

1528

6±3

616

78±

1802

487

0.10

3097

.60.

644

98.4

0.04

5412

.80.

13M

OS-

33.1

2.2

zone

d, C

L-m

ediu

m ro

unde

d co

re0.

0015

121

51.

4768

2733

±39

2720

± 28

00.

1875

1.7

13.6

512.

50.

5281

1.8

0.72

MO

S-33

.13.

1ha

zily

zon

ed d

omai

n in

blu

rry

CL-

dark

gra

in0.

0053

916

30.

3122

225

25±2

125

24±

170

0.16

661.

011

.014

1.4

0.47

941.

00.

70M

OS-

33.1

4.1

zone

d, C

L-da

rk c

ente

r dom

ain

(+th

in ri

m)

4.05

1990

1752

0.91

380

1247

±912

86±

953

0.08

374.

92.

464

4.9

0.21

350.

80.

16M

OS-

34 /

315

7-03

fels

ic/in

term

edia

te m

etav

olca

nic

rock

, Fín

goè

Supe

rgro

upM

OS-

34.1

.1zo

ned,

qui

te d

ark

in C

L0.

0071

532

80.

4714

113

34±1

313

31±

370

0.08

571.

92.

717

2.2

0.22

991.

10.

49M

OS-

34.2

.1zo

ned,

qui

te d

ark

in C

L --

-90

810

381.

1817

913

33±1

013

24±

42-1

0.08

542.

22.

704

2.3

0.22

970.

90.

37M

OS-

34.3

.1zo

ned,

qui

te d

ark

in C

L0.

0056

738

30.

7011

113

19±1

413

25±

420

0.08

542.

12.

674

2.5

0.22

711.

20.

49M

OS-

34.4

.1zo

ned,

qui

te d

ark

in C

L 0.

0072

813

661.

9414

213

21±1

313

14±

57-1

0.08

492.

92.

664

3.1

0.22

751.

10.

35M

OS-

34.5

.1zo

ned,

qui

te d

ark

in C

L -0

.28

461

236

0.53

9013

21±1

413

19±

630

0.08

523.

22.

671

3.4

0.22

751.

20.

34M

OS-

34.6

.1zo

ned,

qui

te d

ark

in C

L -0

.40

374

258

0.71

6411

78±1

712

18±

933

0.08

094.

72.

236

5.0

0.20

051.

60.

31M

OS-

34.7

.1zo

ned,

CL-

med

ium

0.

0016

068

0.44

3213

31±3

913

34±

780

0.08

584.

02.

714

5.2

0.22

933.

30.

63M

OS-

34.8

.1zo

ned,

CL-

med

ium

---

187

780.

4333

1212

±23

1260

± 83

40.

0826

4.3

2.35

64.

70.

2068

2.1

0.43

MO

S-34

.9.1

zone

d, C

l-dar

k ce

nter

dom

ain

0.29

265

166

0.65

4611

76±1

812

19±

694

0.08

093.

52.

231

3.9

0.20

011.

70.

43M

OS-

34.1

0.1

zone

d, C

L-m

ediu

m0.

3723

316

70.

7433

983

±16

1061

± 85

80.

0747

4.2

1.69

74.

60.

1647

1.8

0.39

MO

S-34

.11.

1zo

ned,

CL-

med

ium

0.52

155

650.

4325

1124

±23

1176

± 10

45

0.07

915.

32.

078

5.7

0.19

052.

20.

38M

OS-

34.1

2.1

zone

d, C

L-m

ediu

m

0.50

169

710.

4331

1232

±21

1275

± 97

40.

0832

5.0

2.41

65.

30.

2105

1.8

0.35

Erro

rs a

re 1

-sig

ma;

Pbc

and

Pb*

indi

cate

the

com

mon

and

radi

ogen

ic le

ad p

ortio

ns, r

espe

ctiv

ely.

(1) C

omm

on P

b co

rrec

ted

usin

g m

easu

red 20

4 Pb.T

he re

ject

ed d

ata

are

in it

alic

s.

2σ e

rror

s in

stan

dard

cal

ibra

tion

(not

incl

uded

in a

bove

err

ors)

: 0.2

8% fo

r MO

S-1(

1-11

) and

0.3

7% fo

r MO

S-1(

12-1

7);

0.34

% fo

r MO

S-3,

MO

S-5,

and

MO

S-7;

0.7

7% fo

r Mos

-8; 1

.25%

for

MO

S-12

and

MO

S-15

; 0.3

8% fo

r MO

S-16

; 0.3

7% fo

r M

OS-

19 (9

-18)

, 0.4

0% fo

r MO

S-19

(1-8

), M

OS-

20 a

nd M

OS-

21; 1

.15%

for M

OS-

23, M

OS-

26 a

nd M

OS-

28; 0

.28%

MO

S-29

; 0.7

0%

116


App

endi

x 2.

TIM

S-ID

U-P

b is

otop

ic d

ata

on z

ircon

and

mon

azite

, sam

ples

from

NW

Moz

ambi

que.

Sam

ple

info

rmat

ion

Sam

ple

UPb

206 Pb

/204 Pb

208 Pb

/206 Pb

ISO

TO

PIC

RA

TIO

S1)R

ho2

)

APP

AR

EN

T A

GE

S / M

a±2�

Ana

lyse

d m

iner

al a

nd fr

actio

nw

eigh

tm

gpp

mm

easu

red

radi

ogen

ic20

6 Pb/23

8 U±2

�%

207 Pb

/235 U

±2�

%20

7 Pb/20

6 Pb±2

�%20

6 Pb/23

8 U20

7 Pb/23

5 U20

7 Pb/20

6 Pb

Mos

-2 /

2253

-03

Mon

te D

ombe

gra

nite

, Cas

saca

tiza

Suite

A) z

r >4.

2 g

cm-3

, >75

μm, c

olou

rless

, ± F

e pi

gmen

ted,

trans

pare

nt, p

rism

atic

, abr

aded

10

h0.

4250

582

842

0.14

0.14

490.

651.

511

0.65

0.07

562

0.18

0.97

873

935

1085

±4

B) z

r >4.

2 g

cm-3

, <75

μm, b

row

nish

-yel

low

ish,

± F

e pi

gmen

ted,

shor

t to

med

ium

pris

mat

ic, t

rans

luce

nt,

abra

ded

1 h

0.35

1871

196

330

0.12

0.08

600.

650.

868

0.65

0.07

323

0.40

0.81

532

635

1020

±8

C) z

r >4.

2 g

cm-3

, <75

μm, c

olou

rless

, ± F

e pi

gmen

ted,

trans

pare

nt, p

rism

atic

, abr

aded

4 h

0.28

1053

149

622

0.12

0.12

550.

651.

294

0.65

0.07

480

0.22

0.94

762

843

1063

±4

D) z

r >4.

2 g

cm-3

, >75

μm, b

row

nish

-yel

low

ish,

± F

e pi

gmen

ted,

long

pris

mat

ic, t

rans

luce

nt, a

brad

ed 1

0 h

0.44

1307

152

469

0.12

0.10

060.

651.

029

0.65

0.07

418

0.28

0.91

618

718

1046

±6

Mos

-4 /

1072

-02

aplit

e gr

anite

, Gur

o Su

iteA

) zr>

4.2

g c

m-3

, >75

μm, t

rans

pare

nt, q

uite

col

ourle

ss

pris

mat

ic, i

nclu

sion

s, ab

rade

d 22

h0.

5022

031

7499

0.14

0.13

690.

651.

273

0.65

0.06

741

0.15

0.97

827

833

850±

2

B) z

r>4.

2 g

cm

-3, >

75μm

, tra

nspa

rent

, qui

te c

olou

rless

pr

ism

atic

, inc

lusi

ons

0.55

331

4352

400.

110.

1273

0.65

1.16

80.

650.

0665

40.

150.

9777

378

682

3±2

C) z

r>4.

2 g

cm

-3, <

75μm

, tra

nspa

rent

, qui

te c

olou

rless

pr

ism

atic

, inc

lusi

ons,

abra

ded

17 h

0.31

377

5414

457

0.16

0.13

620.

651.

264

0.65

0.06

733

0.15

0.97

823

830

848±

2

D) z

r>4.

2 g

cm

-3, <

75μm

, tra

nspa

rent

, qui

te c

olou

rless

pr

ism

atic

, inc

lusi

ons

0.48

390

5210

674

0.14

0.12

910.

651.

190

0.65

0.06

684

0.15

0.97

783

796

833±

2

Mos

-6 /

1170

-03

Mas

sang

a gn

eiss

, Mud

zi M

etam

orph

ic C

ompl

exA

) zr>

4.2

g c

m-3

, >75

μm, t

rans

pare

nt, e

long

ated

, ab

rade

d 20

h0.

4621

110

627

622

0.11

0.45

540.

3310

.987

0.33

0.17

497

0.05

0.99

2419

2522

2606

±1

B) z

r>4.

2 g

cm

-3, <

75μm

, tra

nspa

rent

, elo

ngat

ed,

abra

ded

10 h

0.45

258

119

2415

40.

090.

4209

0.35

10.0

170.

350.

1726

00.

060.

9922

6524

3625

83±1

C)

zr>4

.2 g

cm

-3, t

rans

pare

nt, e

long

ated

, abr

aded

30

h0.

5119

096

4366

60.

110.

4583

0.32

11.0

660.

330.

1751

00.

050.

9924

3225

2926

07±1

Mos

-9 /

2007

-03,

gra

nite

, Cas

saca

tiza

Suite

A) z

r >4.

2 g

cm-3

, >15

0μm

, pris

mat

ic, a

lmos

t col

ourle

ss,

trans

pare

nt, i

nclu

sion

s, ab

rade

d 10

h0.

5413

928

4094

0.20

0.18

050.

651.

876

0.65

0.07

539

0.15

0.97

1070

1073

1079

±2

B) z

r >4.

2 g

cm-3

, 150

-75

μm, p

rism

atic

, alm

ost c

olou

rless

, tra

nspa

rent

, inc

lusi

ons,

abra

ded

20 h

0.53

163

3262

110.

190.

1811

0.65

1.88

30.

650.

0754

20.

150.

9710

7310

7510

80±2

C) z

r >4.

2 g

cm-3

, <75

μm

, pris

mat

ic, a

lmos

t col

ourle

ss,

trans

pare

nt, i

nclu

sion

s, ab

rade

d 2

h0.

5723

946

1839

0.19

0.17

410.

651.

818

0.65

0.07

571

0.15

0.97

1035

1052

1088

±2

D) z

r >4.

2 g

cm-3

, 150

-75

μm, p

rism

atic

, alm

ost c

olou

rless

, tra

nspa

rent

, inc

lusi

ons

0.56

179

3525

530.

180.

1793

0.65

1.85

70.

650.

0751

10.

150.

9710

6310

6610

72±2

117


App

endi

x 2.

Con

tinue

d.

Sam

ple

info

rmat

ion

Sam

ple

UPb

206 Pb

/204 Pb

208 Pb

/206 Pb

ISO

TO

PIC

RA

TIO

S1)R

ho2

)

APP

AR

EN

T A

GE

S / M

a±2�

Ana

lyse

d m

iner

al a

nd fr

actio

nw

eigh

tm

gpp

mm

easu

red

radi

ogen

ic20

6 Pb/23

8 U±2

�%

207 Pb

/235 U

±2�

%20

7 Pb/20

6 Pb±2

�%20

6 Pb/23

8 U20

7 Pb/23

5 U20

7 Pb/20

6 Pb

Mos

-10

/ 200

1-02

gra

nite

, Mon

te S

anja

Sui

teA

) zr >

4.2

g cm

-3, >

75μm

, pris

mat

ic, a

lmos

t col

ourle

ss,

trans

pare

nt, a

brad

ed 2

0 h

0.27

108

2441

40.

310.

1676

0.36

1.71

30.

520.

0741

60.

330.

7799

910

1410

46±7

B#2

) zr >

4.2

g cm

-3, >

75μm

, pris

mat

ic, a

lmos

t col

ourle

ss,

trans

pare

nt, a

brad

ed 2

h0.

4713

929

348

0.29

0.15

160.

371.

547

0.56

0.07

405

0.37

0.75

910

949

1043

±8

C#2

) zr >

4.2

g cm

-3, <

75μm

, pris

mat

ic, a

lmos

t col

ourle

ss,

trans

pare

nt, a

brad

ed 1

7 h

0.46

213

4073

30.

310.

1468

0.33

1.49

50.

400.

0738

40.

190.

8888

392

810

37±4

D) z

r >4.

2 g

cm-3

, >75

μm, p

rism

atic

, alm

ost c

olou

rless

, tra

nspa

rent

0.36

306

5447

90.

300.

1351

0.42

1.37

20.

520.

0736

50.

270.

8681

787

710

32±6

Mos

-11

/ 229

7-03

Des

aran

ham

a gr

anite

, Fur

ancu

ngo

Suite

A) z

r >4.

2 g

cm-3

, 150

-75μ

m, p

rism

atic

, red

dish

, tra

nslu

cent

, inc

lusi

ons,

abra

ded

17 h

0.49

324

6132

80.

130.

1525

0.35

1.53

50.

620.

0730

246

.00

0.68

915

945

1015

±9

B) z

r >4.

2 g

cm-3

, 150

-75μ

m, p

rism

atic

, red

dish

, tra

nslu

cent

, inc

lusi

ons

0.54

282

5127

20.

120.

1436

0.34

1.44

00.

650.

0727

40.

490.

6786

590

610

07±1

0

C) z

r >4.

2 g

cm-3

, <75

μm, p

rism

atic

, red

dish

, tra

nslu

cent

, in

clus

ions

, abr

aded

17

h0.

3742

370

466

0.13

0.14

290.

341.

436

0.46

0.07

288

0.28

0.79

861

904

1011

±6

D) z

r >4.

2 g

cm-3

, 150

-75μ

m, p

rism

atic

, red

dish

, tra

nslu

cent

, inc

lusi

ons,

abra

ded

30 h

0.50

140

2611

170.

130.

1705

0.33

1.73

60.

370.

0738

40.

140.

9310

1510

2210

37±3

Mos

-13

/ 603

4-03

gra

nite

, Cas

tanh

o G

rani

teA

) zr >

4.2

g cm

-3, >

75μm

, lon

g pr

ism

atic

, tra

nspa

rent

, ab

rade

d 17

h0.

5425

346

1087

60.

110.

1760

0.65

1.80

70.

650.

0744

70.

150.

9710

4510

4810

54±2

B) z

r >4.

2 g

cm-3

, >75

μm, l

ong

pris

mat

ic, t

rans

pare

nt,

abra

ded

2h0.

5621

138

1418

90.

110.

1760

0.65

1.80

20.

650.

0742

80.

150.

9710

4510

4610

49±2

C) z

r >4.

2 g

cm-3

, <75

μm, l

ong

pris

mat

ic, t

rans

pare

nt,

abra

ded

30 h

0.53

282

5025

921

0.11

0.17

570.

651.

801

0.65

0.07

435

0.15

0.97

1044

1046

1051

±2

D) z

r >4.

2 g

cm-3

, <75

μm, l

ong

pris

mat

ic, t

rans

pare

nt0.

2933

259

8217

0.11

0.17

440.

651.

787

0.65

0.07

428

0.15

0.97

1037

1041

1049

±2

Mos

-18

/ 130

32-0

3 gr

anite

, Mon

te C

apir

impi

ca G

rani

teA

) zr >

4.2

g cm

-3, >

75μm

, pris

mat

ic, b

row

nish

, tra

nslu

cent

to

tran

spar

ent,

abra

ded

10 h

0.53

554

105

1127

0.16

0.16

890.

331.

763

0.35

0.07

573

0.13

0.94

1006

1032

1088

±3

B) z

r >4.

2 g

cm-3

, >75

μm, p

rism

atic

, bro

wni

sh, t

rans

luce

nt

to tr

ansp

aren

t0.

5546

191

421

0.16

0.16

370.

331.

710

0.47

0.07

578

0.30

0.78

977

1012

1089

±6

C) z

r >4.

2 g

cm-3

, <75

μm, p

rism

atic

, bro

wni

sh, t

rans

luce

nt

to tr

ansp

aren

t, ab

rade

d 20

h0.

4456

711

194

50.

170.

1727

0.33

1.80

20.

360.

0757

00.

140.

9210

2710

4610

87±3

D) z

r >4.

2 g

cm-3

, <75

μm, p

rism

atic

, bro

wni

sh, t

rans

luce

nt

to tr

ansp

aren

t0.

4761

611

712

650.

160.

1717

0.33

1.79

20.

350.

0757

20.

120.

9410

2110

4310

88±3

118


App

endi

x 2.

Con

tinue

d.

Sam

ple

info

rmat

ion

Sam

ple

UPb

206 Pb

/204 Pb

208 Pb

/206 Pb

ISO

TO

PIC

RA

TIO

S1)R

ho2

)

APP

AR

EN

T A

GE

S / M

a±2�

Ana

lyse

d m

iner

al a

nd fr

actio

nw

eigh

tm

gpp

mm

easu

red

radi

ogen

ic20

6 Pb/23

8 U±2

�%

207 Pb

/235 U

±2�

%20

7 Pb/20

6 Pb±2

�%20

6 Pb/23

8 U20

7 Pb/23

5 U20

7 Pb/20

6 Pb

Mos

-22

/ 289

3-04

gra

nite

, Ruk

ore

Suite

A) z

r >4.

2 g

cm-3

, 150

-75μ

m, p

rism

atic

, tra

nspa

rent

, ab

rade

d 17

h0.

5910

14

419

0.28

0.02

930.

700.

203

1.90

0.05

011.

600.

5018

618

720

1±39

B) z

r >4.

2 g

cm-3

, <75

μm, p

rism

atic

, tra

nspa

rent

, ab

rade

d 9

h0.

4816

36

508

0.32

0.03

080.

700.

241

1.90

0.05

671.

600.

5019

621

947

9±39

C) z

r >4.

2 g

cm-3

, 150

-75μ

m, p

rism

atic

, tra

nspa

rent

, ab

rade

d 26

h0.

5310

24

382

0.25

0.02

970.

700.

204

1.90

0.04

971.

600.

5018

918

817

9±39

Mos

-24

/ 152

73-0

4 sy

enite

, Gor

ongo

sa In

trus

ive

Suite

A) z

r >4.

2 g

cm-3

, 150

-75μ

m, e

long

ated

, tra

nspa

rent

, qui

te

colo

rless

, abr

aded

17

h0.

5331

9411

215

920.

340.

0284

0.33

0.19

50.

360.

0497

0.14

0.92

181

181

182±

3

B) z

r >4.

2 g

cm-3

, <75

μm, e

long

ated

, tra

nspa

rent

, qui

te

colo

rless

, abr

aded

9 h

0.57

1822

6411

360.

330.

0285

0.33

0.19

50.

380.

0498

0.18

0.88

181

181

183±

4

Mos

-29

/ 192

90-0

4 In

chap

a gr

anod

iori

te, B

arue

Com

plex

A) m

onaz

ite: t

rans

pare

nt, a

brad

ed 2

0 m

inut

es0.

4626

9616

9030

007.

420.

0851

0.92

0.67

40.

980.

0575

0.30

0.95

526

523

509±

7M

os-3

0 / 1

9140

-04

Mes

seca

gra

nodi

orite

, Mav

onde

Com

plex

A) z

r >4.

0 g

cm-3

, >75

μm, t

rans

luce

nt, p

rism

atic

, ab

rade

d 17

h0.

5013

9233

039

240.

090.

2217

0.65

4.07

30.

650.

1332

0.15

0.97

1291

1649

2141

±3

B) z

r >4.

0 g

cm-3

, <75

μm, t

rans

luce

nt, p

rism

atic

, ab

rade

d 9

h0.

4712

6626

924

160.

110.

1964

0.65

3.44

10.

650.

1271

0.15

0.97

1156

1514

2058

±3

C) z

r >4.

0 g

cm-3

, <75

μm, t

rans

luce

nt, p

rism

atic

, ab

rade

d 20

h0.

1312

8827

913

380.

100.

1979

30.

653.

4907

0.65

0.12

790.

150.

9711

6415

2520

69±3

D) z

r >4.

0 g

cm-3

, >75

μm, t

rans

luce

nt, p

rism

atic

, ab

rade

d 30

h0.

2714

6831

341

150.

110.

1974

0.65

3.47

00.

650.

1275

0.15

0.97

1162

1521

2063

±3

E) z

r >4.

0 g

cm-3

, >75

μm, t

rans

luce

nt, p

rism

atic

, ab

rade

d 5

h0.

5014

0633

818

030.

110.

2194

0.65

4.06

00.

650.

1342

0.15

0.97

1278

1646

2154

±3

Mos

-31

/ 684

5-04

Mon

te C

hiss

ui to

nalit

e, B

áruè

Com

plex

A) z

r >4.

0 g

cm-3

, >75

μm, t

rans

pare

nt, e

uhed

ral t

o su

bher

dal,

abra

ded

17 h

0.64

149

2867

250.

220.

1667

0.65

1.79

00.

650.

0779

0.15

0.97

994

1042

1144

±3

B) z

r >4.

0 g

cm-3

, <75

μm, t

rans

pare

nt, e

uhed

ral t

o su

bhed

ral,

abra

ded

9 h

0.44

156

2452

890.

180.

1425

0.65

1.44

60.

650.

0736

0.15

0.97

859

908

1030

±3

C) z

r >4.

0 g

cm-3

, <75

μm, t

rans

pare

nt, e

uhed

ral t

o su

bhed

ral,

abra

ded

20 h

0.45

268

3613

252

0.16

0.12

750.

651.

235

0.65

0.07

020.

150.

9777

481

693

5±3

D) z

r >4.

0 g

cm-3

, >75

μm, t

rans

pare

nt, e

uhed

ral t

o su

bhed

ral,

abra

ded

30 h

0.33

136

2563

260.

210.

1653

0.65

1.77

40.

650.

0779

0.15

0.97

986

1036

1143

±3

1) Is

otop

ic ra

tios c

orre

cted

for f

ract

iona

tion,

bla

nk (3

0-50

pg)

, and

age

rela

ted

com

mon

lead

(Sta

cey

and

Kra

mer

s, 19

75; 20

6 Pb/20

4 Pb±0

.2; 2

07Pb

/204 Pb

±0.1

;208 Pb

/204 Pb

±0.2

;2)

Err

ors f

or c

omm

on le

ad c

ompo

sitio

n of

low

-U, y

oung

zirc

ons i

n sa

mpl

e M

OS-

22 a

re 20

6 Pb/20

4 Pb±0

.5;20

7 Pb/20

4 Pb±0

.3;20

8 Pb/20

4 Pb±0

.5 ).

3)

Rho

=Err

or c

orre

latio

n be

twee

n 207

Pb/23

5 U a

nd 20

6 Pb/23

8 U ra

tios.

Abb

revi

atio

ns: z

r=zi

rcon

119


Appendix 3. Sm-Nd isotopic data, samples from NW Mozambique.

mesoarchaean to lower jurassic u-pb and sm-nd ages...

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