Acta Mineralogica-Petrographica, Szeged 2004, Vol. 45/2, pp. 21-28

ACTA Mineralógica Petrographica

O C C U R R E N C E A N D PETROLOGY OF L A M P R O P H Y R E S FROM THE N O R T H E R N PART OF T H E DITRÄU ALKALINE MASSIF, EASTERN CARPATHIANS, ROMANIA

A N I K Ó B A T K I 1 , ELEMÉR P Á L - M O L N Á R A P O L K A B Á R D O S S Y 2

1 Department of Mineralogy, Geochemistry and Petrology, University of Szeged, H-6722 Szeged, Egyetem u. 2-6, Hungary 2 " Móra Ferenc Museum. Museum of Csongrád County Government, H-6720 Szeged, 1-3. Roosevelt square, Hungary

e-mail: batki@geo.u-szeged.hu

ABSTRACT

Lamprophyre dykes and dyke swarms exposed in the northern part of the Ditràu Alkaline Massif (DAM) intersect granitoids, syenitoids, hornblendites and diorites. Accordingly to the lamprophyres geological conditions, they are the last stage of the DAM's magmatic evolution. Most of the lamprophyres are composed of phenocrysts of augite which are included in a matrix consisting of fine-grained kaersutite-ferrokaersutite, hastingsite-magnesiohastingsite, biotite and interstitial albite-oligoclase-andesine. Other lamprophyre varieties have augite and/or melanite phenocrysts. Their microcrystalline groundmass is composed of mainly arfvedsonite, biotite, albite-oligoclase and orthoclase. Both lamprophyre types contain felsic globular structures filled with carbonatic and/or feldspathic minerals. Mineral assemblage and major element geochemical composition indicate that they are camptonites within alkaline lamprophyres and kersantites within calc-alkaline lamprophyres. Key words: camptonite, kersantite, Ditràu Alkaline Massif, Eastern Carpathians, Romania

INTRODUCTION Lamprophyres are a group of H 2 0 and/or C02-rich

alkaline rocks ranging from sodic to potassic and from ultrabasic to intermediate. Commonly, they exhibit a distinctive inequigranular texture resulting from the presence of ferromagnesian macrocrysts set in a fine-grained matrix. Irregular to spherical, felsic globular structures are widespread. Lamprophyres typically form en echelon dykes, sills, pipes and vents which may aggregate into extensive swarms or clusters (Rock, 1991).

The mineral composition, structure and magmatic evolution of the Ditràu Alkaline Massif (DAM) (Transylvania, Romania) have been discussed for more than 150 years. During this time numerous famous geologists attempted to explain the genesis of DAM (Pál-Molnár, 1994). However, the origin of lamprophyre dykes intersecting the different rock-types (granitoids, syenitoids, hornblendites and diorites) of DAM and the genesis of lamprophyre-magma (separation of co-magmatic and co-genetic sequences) has slightly been discussed. So far, only petrographical and a few chemical analyses were made on lamprophyre bodies, hence, the petrological and petrotectonical interpretation of these rocks would greatly contribute to understand the genetics of DAM. This paper presents a comprehensive report of currently known lamprophyres from DAM and focuses on their occurrence, pétrographie features, classification and major element geochemistry.

GEOLOGICAL SETTING The DAM is a Mesozoic alkaline igneous complex and

situated in the S-SW part of the Giurgeu Alps belonging to the Eastern Carpathians (Romania) (Fig. 1A). Diameter of its surface is 19 km in NW-SE and 14 km in SW-NE directions,

respectively; its area is 225 km2, including the bordering zones as well (Pál-Molnár, 1994a, b). This body intruded into the pre-Alpine metamorphic basement complexes of the Bucovinian Nappe Complex located on the east side of the Culimani-Gurghiu-Harghita Neogene-Quarternary calc-alkaline volcanic arc, and took part in the Alpine tectonic events together with these metamorphic rocks (Pál-Molnár, 2000). The massif touches four pre-Alpine complexes of the Bucovinian Nappe Complex: I. Bretila-Raráu series, 2. Negri^oara series, 3. Rebra series 4. Tölgyes series. The first three are rock series of Precambrian amphibolite facies, while the fourth is a polimetamorphic unit of greenschist facies, presumably Late Paleosoic concerning its age (Balintoni, 1981; Kráutner and Bindea, 1995).

The Massif is covered by andesitic piroclasts and agglomerates of the volcanic arc and Pliocene-Pleistocene sediments of the Giurgeu- and Jolotca-basins. Its direct contact with sedimentary rocks could not be observed. The magmatic evolution of the DAM passed off when the Getida-Bucovinian Microplate came away from the Eurasian margin (Krautner and Bindea, 1998) which began with the opening of the Tethys in the Triassic.

The DAM is covered by a network of two major (NE-SW and NW-SE) and two secondary (N-S and E-W) fault systems. These two fault generation affect both the massif and the adjacent crystalline rocks. The massif was broken into blocks along the major faults, and lower and higher compartments were formed. Very important vein-like mineralization is associated with the secondary fault of E-W direction (Pál-Molnár, 2000).

The center of the DAM was formed by nepheline syenite, which is surrounded by syenite and monzonite. The northwestern and northeastern parts are composed of homblendite, diorite

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22 A. Batkietal.

Pre-Al pi ne metamorphic basement

I Hornlelses B l f f l I Jolotca complex I Hnrnblendite

Gabbro. diurne, monzonite Alkali gabbro (Ditro-Essexites) (Gudücz complex)

line svenite and of Jolotca comple-

E S

Syeniie i (ir.initc

Fig. 1. (A) Schematic map of the Eastern Carpathians region after Sandulescu et al. (1981); (B) Geological map of the Ditrau Alkaline Massif after Krautner and Bindea(1998).

(called Tarnica Complex, Pál-Molnár, 2000), monzonite and alkali granite (Fig. 1B). The whole complex is cut by late-stage lamprophyre, alkali feldspar syenite and tinguaite dykes.

According to Morogan et al. (2000) the rocks of the DAM are originating from an OIB character, basanitic magma, which is formed from the low grade melt of the asthenosphere of garnet-lherzolite composition. The multi-stepped process of magma formation refer to a long lasting mantle upwelling. Mantle-derived basic magmas and magmas which were silica saturated and oversaturated, formed during their contamination with the crust, fractionated further until the appearance of alkali granite. Nepheline syenites represent the last large magma intrusion phase of the DAM, their formation can be explained by a basanitic parent magma and a low grade crustal assimilation. Morogan et al. (2000) claimed that volatile content had an important role in the development of the DAM, which is proved by a wide contact zone between the DAM and metamorphic rocks, the appearance of amphiboles and biotites in ultrabasic rocks at the expense of pyroxenes and olivines, and the presence of cancrinite, sodalite and scapolite in nepheline syenites. They regarded ultrabasic rocks as cumulates of mantle origin, which presumably crystallised as clinopyroxenite containing olivine, and went through metasomatosis resulting amphiboles. Based on the element distribution of amphiboles and pyroxenes Morogan et al. (2000) deduced the process of differentiation in the DAM from alkali gabbros to monzonites and alkali syenites.

Pál-Molnár (2000) suggested a two-stage emplacement with the mid-Triassic - lower Jurassic formation of ultramafic rocks followed by formation of nepheline syenites by fractionation, and alkali granites by fractionation and assimilation. The second period (mid-Jurassic - lower Cretaceous) involved the emplacement of syenites and diorites, latter as hybrid rocks of hornblendites and syenites.

LAMPROPHYRE RESEARCH IN THE AREA OF DITRÁU ALKALINE MASSIF

On the territory of the DAM lamprophyres, as microcrystalline amphibole rocks were first analysed by

Fellner (1867). His samples were originating from the estuary of the Orotva (Jolotca)- Tâszok (Tease) Creek, where according to Herbich (1878) they broke through syenites in the form of dykes. One of the samples had a chemical composition closest to alnôites. The other, microcrystalline amphibole rock studied was much more acidic, and turned to be a typical camptonite.

When analysing the rocks of the DAM, Herbich already in 1871 recognised 'green rocks' (lamprophyres) occurring in the dykes.

Berwerth (1905) also found camptonite in outcrops along the Ditro (Ditrau)-Tolgyes (Tulghe§) road.

Mauritz (1912) published detailed penological description and geochemical data on some basic dykes intergrowing

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Occurrence and petrology of lamprophyres from the northern part of the Ditrau Alkaline Massif 23

the DAM. One of the lamprophyre dykes, 4-5 m wide, with a N-S strike in a standing position, was originating from the Varpatak valley, and contained small syenite inclusions, at some places thin pegmatite veins. Its rock is dark greenish grey, homogeneous with relatively large biotite aggregates. Characteristic components are: amphibole, biotite, microcline, oligoclase albite, nepheline, cancrinite, apatite, magnetite, epidote and muscovite, which is probably of secondary origin. Its texture is panidiomorphic-granular. Based on its mineral components the rock is from a more acidic type than camptonite, which is also backed by its chemical composition. Another camptonite, described by Mauritz (1912), was originating from a 3 m wide dyke of NW-SE strike, found also at the Ditro-Tolgyes roadside outcrop. On the sides of the dyke the rock is fine grained, while inside coarse-grained. Its colour is dark, greyish black. The main rock forming mineral is brown amphibole, further components are biotite, oligoclase, a little microcline, titanite, apatite, magnetite containing titanium and surrounded by a leucoxene zone, secondary epidote and chlorite. The next camptonite sampled by Mauritz (1912) at the Ditro-Tolgyes roadside outcrop was originating from a 1 m wide dyke, which was formerly described by Szadeczky (1899), too. The texture of the rock is poikilitic, its rock forming minerals are: a little diopside, biotite, hastingsite amphibole, oligoclase albite, calcite, epidote, abundant titanite, hematitised magnetite and some apatite. The fourth lamprophyre dyke described by Mauritz (1912) was found at the estuary of the Orotva-Taszok Creek in an amphibolic, biotitic mother rock, which is built up by 10-15 cm thick, dyke-like, compact, dark coloured camptonite. The strike of the dyke is N-S its dip is almost vertical. The texture of the rock is panidiomorphic-granular, components are: amphibole, biotite, oligoclase, titanite, apatite, epidote and muscovite. Szadeczky (1899) also named the mother rock of this dyke as camptonite, which he found on both sides of the Orotva Creek at the estuary of the Taszok Creek. He suggested that these represent a thicker dyke, or a small stock-like body. Mauritz (1912) reinforced the latter idea, based on the large mass of the formation, the aplite and real camptonite dykes intruding the mother rock and its transition into amphibole peridotite towards the North and West. All these led to the conclusion that the body is not a thick dyke, but rather a result of basic differentiation. On the basis of its chemical composition the mother rock falls into the group of diorites, shonkinites (nepheline syenite) and theralites (foid diorite, foid gabbro).

Mauritz et al. (1925) made a chemical analysis also on a camptonite during the investigation of the rock types of DAM. The compact, dark coloured rock, found at the right bank of Orotva Creek, right downstream of its confluence with the Taszok Creek, broke through hornblendite in the form of a thin dyke. Its texture was close to panidiomorphic-granular. Its most important rock forming mineral is amphibole, others are biotite and oligoclase. It also contains titanite in a large quantity, apatite, pyrite, epidote, and a little magnetite, and at some places thin veins with epidote also appear.

When studying the differentiation sequence of the DAM, Mauritz (1925) found on the basis of differentiation diagrams that camptonites represented essexite- (foid monzodiorite,

foid monzogabbro)-, essexitgabbroid-, theralite- (foid diorite, foid gabbro), theralitgabbroid-, and even gabbrodiorite magma.

Vendl (1926) as a supplement to the chemical analysis of Mauritz et al. (1925), analysed two camptonites for determining their place in the chemical taxonomy, and found that they are diaschist melanocratic dykes. The first sample was a biotitic amphibole-camptonite (Várpatak), a fine grained dark coloured rock with white calcite almonds. Feldspars, which often calcitisized, formed a glass-like matrix. The main rock forming mineral is amphibole. Another important mafic component is biotite, which developed probably from the amphibole. Biotite is accompanied by pennine. The transformation of amphibole at some places is so advanced, that they are displaced by aggregates of small mica flakes, however usually the original amphibole can still be recognised. During the transformation leucoxenisation and ore formation was also characteristic. He found strongly leukoxenised magnetite with titanium content. Based on its texture it fell closer to monchiquite of vitreous matrix, while its chemical composition was referring rather to that of camptonite. The second sample was fine grained, at some places of spongy structure, dark, greenish black amphibole-camptonite (Károly Creek). Its texture is panallotriomorphic, granular its major mafic components are brown and blue amphibole, which are often intercrescenced. The chloritization of amphibole and biotite, as well as the occurrence of leucoxene aggregates in chloritic parts is frequent. Accessories are apatite and magnetite.

When displaying the rocks of the DAM, Streckeisen (1954) mentioned camptonite and spessartite as dyke rocks. According to his description lamprophyres are of varied width and broke through all the rocks of the massif. They most frequently occurred in the diorite zone, and concerning their chemistry they stand closest also to these rocks. Based on this observation, he came to a conclusion that concerning its genetics lamprophyres are part of the massif, they intruded after the solidification of rocks, but before the termination of magmatic activity.

Streckeisen and Hunziker (1974) attempted to explain the formation of the DAM with magmatism. They reasoned magmatic origin with the presence of tinguaite and camptonite dykes, which were proved to be magmatic intrusions with a chemical composition very close to nepheline syenites and diorites, and intersected both the massif and surrounding rocks with well defined contacts.

Anastasiu and Constantinescu (1982) distinguished 9 dyke-fields in the DAM. They mentioned kersantite, spessartite and vogezite from Pietrari-Tászok valley, vogezite and spessartite from Orotva valley, kersantite, spessartite, camptonite from Ditró-Güdiic valley, and spessartite and camptonite from Csanód valley.

Jakab (1998) studied lamprophyres in the Tölgyes (Tulghe§) Series and on the territories of Vasláb-Balán-Holló-Bélbor. According to his investigations, based on their geochemical compositions, lamprophyres of the DAM are mostly camptonites and spessartites, and rarely vogezites. He observed that the TiO?-content of lamprophyres is high, and concerning their genetics they might be connected to several rock types of the DAM, which he explained by hybridisation processes in the massif.

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Fig. 2. Geological map of the northern part of the Ditrau Alkaline Massif; • Sampling sites.

Occurrence and petrology of lamprophyres from the northern part of the Ditrau Alkaline Massif 25

O C C U R R E N C E AND S A M P L I N G

The studied area is the northern part of the Ditrau Alkaline Massif: the Orotva Creek and its northern affluents from Nagyág Creek to Tarnitpa Creeks (Fig. 2). The 20 cm-2 m wide lamprophyre dykes and dyke swarms (Fig. 3) intersect different rock-types, (granitoids, syenitoids, hornblendites, diorites) They outcrop in alkaline granites (Nagyág and Török Creeks), in syenitoids and hornblendites and diorites of Tarnica Complex (Orotva, Tászok, Fülöp, Gudu Creeks). Contacts of lamprophyre dykes with the wallrocks are sharp (Fig. 4). One of the lamprophyre bodies from Tászok Creek is cut by a cm wide alkaline feldspar syenite dyke (Fig. 4D). Both lamprophyres and the country rocks are less or largely altered. There are numerous faults on the territory, from which several cut lamprophyre dykes, too. The studied rocks (55 samples) were collected from nine natural outcrops of six creeks (Fig. 2). Field relations suggest last stage emplacement of lamprophyre and alkaline feldspar syenite dykes in the DAM's magmatic evolution.

P E T R O G R A P H Y

The optical analyses were performed by NIKON Microphot-FXA polarizing microscope. Based on petrographic investigations there are two types of lamprophyres in the studied area.

(1) A more abundant dark-grey, greenish-grey melanocratic (mafic) lamprophyre type (Fig. 5A) with augite phenocrysts (Fig. 5B) and kaersutite-ferrokaersutite, hastingsite-magnesio-hastingsite and biotite micro-phenocrysts (Orotva, Tászok, Fülöp, Gudu, Nagyág and Török Creeks).

(2) Light-grey, mesocratic (intermediate) varieties of lamprophyres (Fig. 5C) with phenocrysts of augite or melanite (titanium-rich variety of andradite) (Fig. 5D) (Nagyág and Török Creeks).

The lamprophyre dykes show felsic globular structures (up to 11 mm) filled with combinations of phenocrystic calcite, feldspars, feldspathoids and biotite ± accessory minerals (Fig. 5E). The texture is typically panidiomorphic, porphyritic, microporphyritic (Fig. 5A, C) and at some places vitrous in contact zones. The fine-grained matrix

I I Lamprophyre I+ + + + 3 Granite Tectonic fault Fig. 3. (A, B, C) Occurrence of lamprophyre dykes in the northern part of Orotva Creek, Ditrau Alkaline Massif; (D, E, F) Plan views of the geometric form of lamprophyre bodies (Orotva Creek, DAM).

Lamprophyre

3 cm Alkaline feldspar syenite

Fig. 4 Contacts of lamprophyre dykes with A. granite; B. hornblendite; C. syenite; D. alkaline feldspar syenite from Orotva-Creek, DAM. The penknife is 10 cm.

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consisting of kaersutite-ferrokaersutite, hastingsite-magnesiohastingsite displaying preferred orientation due to the magma flow at some places, biotite and interstitial albite-oligoclase-andesine ± calcite in mafic types, and arfvedsonite, biotite, albite, orthoclase in mesocratic types, compose 83-100 vol% of the lamprophyres. The matrix feldspars are more abundant in the mesocratic samples than in the mafic dykes (Fig. 5C). Accessory minerals are titanite, apatite, magnetite, galenite and zircon. Plagioclase feldspar xenocrysts can also be found in some samples from Török Creek. These are originating from the surrounding granitoids or syenitoids.

Most of the lamprophyres are affected by alteration. In mafic dykes augites are simply uralitized or altered into tremolite ± actinolite ± chlorite ± magnetite ± calcite ± allanite assemblages (Fig. 5F). Kaersutites-ferrokaersutites have narrow rims of actinolite. Most hastingsites-magnesio-hastingsites contain secondary magnetite needles indicating magmatic resorption of the amphiboles, others are converted to fine-grained aggregates of biotite. Primary biotites are chloritised, the matrix albite-oligoclase-andesine and orthoclase are sericitized. The melanites of mezocratic lamprophyres are totally or partially replaced by chlorite ± biotite (Fig. 5D). Some of the samples contain pseudomorphs after euhedral amphibole phenocrysts formed by epidote and chlorite ± calcite. Calcite, epidote and opaque mineral veins penetrate both lamprophyre types.

M A J O R E L E M E N T G E O C H E M I S T R Y

The major element compositions of the samples representing the main lamprophyre types were determined by

A. Batki etal.

Fig. 5 Photomicrographs showing the mineral composition and texture of the studied lamprophyres; (A) sample ÁGK-6765 (Török Creek) panidiomorphic texture of the melanocratic (mafic) lamprophyre type with kaersutite in the groundmass (IN, x50); (B) sample ÁGK-7292 (Tarnica Creek) augite phenocryst ( IN, 50x); (C) sample ÁGK-7306 (Nagyág Creek) panidiomorphic texture of the mesocratic (intermediate) lamprophyre type with arfvedsonite in the groundmass ( IN, x50); (D) sample ÁGK.-6759 (Török Creek) melanite phenocryst ( IN, 50x); (E) sample ÁGK-7294 (Tarnica Creek) felsic globular structure, ( IN, x50); (F) sample ÁGK-7292 (Tarnica Creek), pseudomorph after euhedral augite phenocryst formed by tremolite, chlorite and magnetite ( IN, x50). Abbreviations: aug: augite, arf: arfvedsonite, bt: biotite, cal: calcite, chl: chlorite, grt: garnet, krs: kaersutite, mag: magnetite, pi: plagioclase, tr: tremolite (abbreviations after Kretz, 1983).

Table 1. Major element data for alkaline and calc-alkaline lamprophyres from the northern part of Ditrau Alkaline Massif. Camptonites from Tarnica Complex Camptonites from Török, Nagyág Creek Kersantites from Török and Nagyág Creek

wt% AGK- AGK- AGK.- AGK- AGK- AGK- AGK- AGK- AGK- AGK- AGK- AGK- AGK- AGK- AGK- AGK- AGK- AGK. AGK-

wt% 6715 7292 7296 7297 7300 7301 7302 7351 6765 7286 7289 7290 7320 6759 6771 7306 7333 7336 7338

SiO, 45,29 45,22 46,26 48,61 46,46 43,27 46,54 44,79 41,79 48.39 44,35 43,32 47,84 54,10 54,50 57,50 56,00 55,90 55,90

AI2O3 14,70 12,52 15,68 15,16 15,97 14,47 16,07 15,64 14,64 18,20 15,42 14,82 16,40 19,97 20,10 21,81 20,44 21,15 20,56

FeO' 13,00 10,47 9,81 9,96 11,69 12,92 10,59 12,80 13,88 9,59 13,99 13,66 11,03 5,11 5,32 3,99 4,08 3,72 3,97

MnO 0,16 0,16 0,17 0,15 0,17 0,20 0,19 0,19 0,25 0,27 0,26 0,25 0,15 0,14 0,15 0,16 0,28 0,21 0,21

MgO 7,05 10,01 6,52 7,14 5,63 6,60 4,87 6,41 6,24 3,79 5,91 6,01 4,54 2,61 2,92 0,96 0.90 0,68 0,87

CaO 8,88 8,85 8,28 7,30 8,62 8,83 8,79 9,56 8,54 7,53 7,68 9,49 7,38 3,86 3,59 2,15 1,50 1,36 1,77

N a : 0 4,00 3,01 4,56 4,49 4,40 3,02 4,08 3,24 3,57 4,13 2,92 3,45 3,92 4,92 4,84 9,38 8,41 7,38 9,62

K,O 1,96 2,36 2,37 2,25 2,29 3,57 2,43 2,60 2,30 3,52 3,30 1,90 2,00 5,78 5,92 5,47 5,06 4,85 4,09

TiOi 3,60 2,08 2,16 2,12 3,34 3,42 2,94 3,78 3,47 2,68 3,42 3,45 2,78 1,02 1,07 0,50 0,41 0,42 0,55

Total 98,64 94,67 95,81 97,18 98,57 96,30 96,49 99,01 94,68 98,08 97,25 96,35 96,05 97,51 98,40 101,9 97,07 95,66 97,54

FeO' as total iron.

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Occurrence and petrology of lamprophyres from the northern part of the Ditrau Alkaline Massif 27

inductively coupled plasma-atomic emission spectrometry (ICP-AES) at the Stockholm University.

The concentration of major oxids for the analysed samples (Table 1) falls within the range of alkaline (AL) and calc-alkaline lamprophyres (CAL) (Fig. 6A, B, C) as characterised by Rock (1991).

Camptonites are alkaline lamprophyres with more plagioclase than alkali feldspar, can include Na-foids and amphibole dominates over biotite (Rock, 1991). The mafic group of the lamprophyres from Orotva, Tászok, Fülöp, Gudu, Nagyág and Török Creeks are found to be camptonites and characterized by low Si02 contents, high contents of TiOj and alkalies (Table 1).

Kersantites are calc-alkaline lamprophyres with plagioclase > alkali feldspar and without Na-foids or leucite (Rock, 1991). The intermediate group of lamprophyres from

Nagyág and Török Creeks seem to be kersantites, however they have much higher A1203 content (up to 21.8%) and N a 2 0 content (4.8-9.6%) than average (14.0% A1203; 2.7% Na 2 0, Rock 1991) for calc-alkaline lamprophyres. In turn FeO' (3.9-5.3%), MgO (0.68-2.9%) and CaO contents (1.5-3.8%) are lower than average for CAL (8.2% FeO1; 7.0% MgO; 7.0% CaO; Rock, 1991).

Plotting all analyses on standard discrimination diagrams, distribution of lamprophyres show that they are alkaline (Fig. 6D) according to the criteria of Irvine and Baragar (1971) and metaluminous (Fig. 6E) (Maniar and Piccoli, 1984).

C O N C L U S I O N S

This study focused on the lamprophyre dykes occurring in the northern part of the Ditrau Alkaline Massif where the different varieties of lamprophyres crosscut hornblendites,

Fig. 6. (A, B) Simple plots discriminating the whole-rock compositional fields of lamprophyres (Rock, 1987), UML-Ultramafic Lamprophyres, AL-Alkaline Lamprophyres, CAL-Calc-Alkaline Lamprophyres, LL-Lamproites; (C) SiO? VJ. K 2 0 (Gill, 1981) comparing whole-rock compositional fields of lamprophyres after Rock (1987); (D) S i0 2 vs. Na 2 0+K 2 0 , after Irvine and Baragar (1971); (E) Plots of molar ratios Al 2 0 3 / (Na 2 0+K 2 0) (A/NK) vs. molar ratios Al 2 0 3 / (Ca0+Na 2 0+K 2 0) (A/CNK), Maniar and Piccoli (1989); O Camptonites from Tarnica Complex (DAM), • Camptonites from Nagyág and Török Creeks (DAM), O Kersantites from Nagyág and Török Creeks (DAM)

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