geochemical characteristics of the río verde complex ...pcigr.eos.ubc.ca › publications ›...

Lithos 114 (2010) 168–185

Contents lists available at ScienceDirect

Lithos

j ourna l homepage: www.e lsev ie r.com/ locate / l i thos

Geochemical characteristics of the Río Verde Complex, Central Hispaniola:Implications for the paleotectonic reconstruction of the Lower CretaceousCaribbean island-arc

Javier Escuder-Viruete a,⁎, Andrés Pérez-Estaún b, Dominique Weis c, Richard Friedman c

a Instituto Geológico y Minero de España, C. La Calera 1, Tres Cantos, 28760 Madrid, Spainb Instituto Ciencias Tierra Jaume Almera-CSIC, Lluís Solé Sabarís s/n, 08028 Barcelona, Spainc Pacific Centre for Isotopic and Geochemical Research, University of British Columbia, 6339 Stores Road Vancouver, Canada BC V6T 1Z4

⁎ Corresponding author. Instituto Geológico yMineroTres Cantos, Madrid. Spain. Tel.: +34 917287242.

E-mail address: [email protected] (J. Escuder-Virue

0024-4937/$ – see front matter © 2009 Elsevier B.V. Adoi:10.1016/j.lithos.2009.08.007

a b s t r a c t
a r t i c l e i n f o
Article history:Received 20 November 2008Accepted 12 August 2009Available online 23 August 2009

Keywords:Island-arcBack-arc basinMantle meltingHispaniolaCaribbean plate

New geochronological, trace element and Sr–Nd isotope data for metabasalts, dolerites and amphibolitesfrom the Río Verde Complex, Central Hispaniola, are integrated with existing geochemical data for maficvolcanic rocks and metamorphic derivatives from the Los Ranchos, Amina and Maimón Formations, givingnew insights into magma petrogenesis and paleotectonic reconstruction of the Lower Cretaceous Caribbeanisland-arc–back arc system. U–Pb and 40Ar/39Ar age data show that the Río Verde Complex protoliths were inpart coeval with volcanic rocks of the Los Ranchos Formation (Upper Aptian to Lower Albian). Thegeochemical data establish the existence of gradients in trace element parameters (Nb/Yb, Th/Yb, Zr/Yb, Zr/Ba, and normalized Ti, Sm, Y and Yb abundances) and Nd isotope compositions from throughout Hispaniola,which reflect differences in the degree of mantle wedge depletion and contributions from the subductingslab. The Río Verde Complex mafic rocks and some mafic sills and dykes intruding in the Loma CaribePeridotite, have a transitional IAT to N-MORB geochemistry and a weak subduction-related signature, andare interpreted to form in a rifted arc or evolving back-arc basin setting. The Los Ranchos, Amina andMaimón Formations volcanic rocks have arc-like characteristics and represent magmatism in the volcanicfront. Trace element and Nd isotope modeling reproduce observed data trends from arc to back-arc andsuggest that the variations in several geochemical parameters observed in a SW direction across theCaribbean subduction system can be explained from the progressively lower subduction flux into aprogressively less depleted mantle source. The low Nb contents and high (εNd)i values in both arc and back-arc mafic rocks imply, however, the absence of a significant Lower Cretaceous plume enriched component. Inorder to explain these observations, a model of proto-Caribbean oceanic lithosphere subducting to the SW atleast in the 120–110 Ma interval, is proposed to cause the observed magmatic variations in the LowerCretaceous Caribbean island-arc–back-arc system. In this context, arc rifting and initial sea-floor spreading toform the Río Verde Complex protoliths occurred in the back-arc setting of this primitive island-arc, built onthe NE edge of the Caribbean plate.

© 2009 Elsevier B.V. All rights reserved.

1. Introduction

Island-arcs develop because of subduction of oceanic lithospherebeneath another oceanic plate. The aqueous fluids and/or hydrousmelts released from the subducting slab and their reaction with theoverlying mantle wedge provide the prime control on arc magmagenesis (Hawkesworth et al., 1993; Pearce and Peate, 1995; Wood-head et al., 1998; Stern, 2002). Magma genesis processes alongconvergent plate boundaries mainly include: (1) adiabatic upwellingof asthenospheric mantle induced by slab penetration (Peacock and

de España. C. La Calera 1, 28760

te).

ll rights reserved.

Wang, 1999; Gerya et al., 2004); (2) partial melting of the mantlewedge as a result of the addition of slab-derived fluids (Arculus andPowell, 1986; Pearce and Parkinson, 1993; Schmidt and Poli, 1998;Hochstaedter et al., 2001;Martinez and Taylor, 2002); and (3)meltingof the subducted slab and addition of the resultant melts to themantlewedge (Defant and Drummond, 1990; Yogodzinski et al., 2001;Tatsumi and Hanyu, 2003). The compositions of arc lavas can varyacross and along individual arcs. This probably results from: (1)compositional differences in subducted slab rocks (Plank and Langmuir,1993); (2) differences in the dehydration or melting conditions of slabmaterials (Defant and Drummond, 1990); (3) differences in degree ofpartial melting in the mantle wedge (Pearce and Parkinson, 1993); (4)differences in the volume of slab-derived components added to theoverlyingmantle wedge (Kelemen et al., 2003; Singer et al., 2007); and

mailto:[email protected]://dx.doi.org/10.1016/j.lithos.2009.08.007http://www.sciencedirect.com/science/journal/00244937

169J. Escuder-Viruete et al. / Lithos 114 (2010) 168–185

(5) pre-existing mantle heterogeneity (Leat et al., 2004). As such, thecomposition of island arc lavas can be formed by a variety of processes;however, identifying which processes are involved in the petrogenesisof any particular lava is often difficult.

Outcrops of Late Aptian to Lower Albian volcanic rocks in theGreater Antilles are the oldest known arc-related strata of theprimitive Caribbean island-arc. Geochemical studies of these rocksindicate a broad compositional spectrum across and along the arc thatmake their interpretation difficult in terms of subduction-relatedpetrogenetic models (Lebrón and Perfit, 1994; Kerr et al., 1999; Jollyet al., 2001, 2006; Marchesi et al., 2006, 2007; Jolly et al., 2007, forexample in Hispaniola (Lewis et al., 2002; Escuder-Viruete et al., 2006,2007a,b,c). Further, these volcanic rocks are of considerable signifi-cance in the debated tectonic reconstructions of initial subductionpolarity and magma genesis processes, along the long-lived (EarlyCretaceous to Mid-Eocene) destructive plate margin separating theNorth American and Caribbean plates.

In this paper, we present new regional petrologic, U–Pb/Ar–Argeochronological, trace element and Sr–Nd radiogenic isotope data forthe Río Verde Complex mafic igneous rocks in Central Hispaniola, thatallow us to relate it to the Lower Cretaceous Caribbean island-arc–back arc system. These data in conjunction with published data ofcoeval subduction-related units in Hispaniola allow us to addressthree main questions. These are: (1) nature and age of the Río VerdeComplex protoliths; (2) tectonic setting of origin of the complex andrelations with coeval magmatic units; and (3) polarity in the intra-oceanic Caribbean subduction system.

2. Geodynamic setting

2.1. The Caribbean island-arc

The Caribbean island-arc is subdivided into three domains: (1) theextinct Early Cretaceous to Paleogene Greater Antilles in the north,including Cuba, Jamaica, Hispaniola, Puerto Rico, and the VirginIslands; (2) northern South America, including Tobago, Margarita, andColombian/Venezuelan allochthons in the south; and (3) thevolcanically active Lesser Antilles in the east, which rest on buriedremnants of the south-eastern extension of the Cretaceous arc. In theGreater Antilles, Early Cretaceous (Aptian) to mid-Eocene island-arcvolcanic rocks are traditionally subdivided (Donnelly et al., 1990) intoa lower primitive island-arc suite (PIA), consisting predominantly ofspilitized tholeiitic basalt and dacitic–rhyolitic lavas, and an overlyingbasaltic to intermediate calc-alkaline suite (CA). PIA lavas typicallyhave low large-ion lithophile elements (LILE), rare earth elements(REE), and high field strength elements (HFSE) abundances, lowradiogenic Pb, and near-horizontal primitive-mantle normalized REEpatterns; younger CA lavas are distinguished from PIA by elevatedincompatible element abundances and variably enriched REE pat-terns. Recent studies, however, have demonstrated that Caribbeanisland-arc volcanism produced basalt compositions with a broadrange of LREE/HREE values and Sr–Nd–Pb isotope compositions,reflecting a wide variation in mantle sources and proportions ofsubducted sediments during its 80 Ma long eruptive history, fromLower Cretaceous to Late Eocene (c.a. 125 to 45 Ma; Kerr et al., 1999;Lewis et al., 2000; Jolly et al., 2001; Lewis et al., 2002; Jolly et al., 2006;Marchesi et al., 2006; Escuder-Viruete et al., 2006; Jolly et al., 2007;Marchesi et al., 2007; Escuder-Viruete et al., 2007a, 2008).

The PIA suite is represented by the Water Island Formation in theVirgin Islands (Rankin, 2002; Jolly and Lidiak, 2006), volcanic phases Iand II in Central and Northeastern Puerto Rico (pre-Robles and pre-Santa Olaya Lava units; Jolly et al., 2001, 2006), clasts of PIA rocks inthe pre-Camujiro sedimentary rocks near the province de Camagüeyand Los Pasos Formation in Central Cuba (Kerr et al., 1999; Proenzaet al., 2006), and the Los Ranchos, Amina and Maimón Formations inthe Central and Eastern Cordilleras of Hispaniola (Kesler et al., 1990;

Draper and Lewis, 1991; Lebrón and Perfit, 1994; Kesler et al., 2005;Escuder-Viruete et al., 2006; Fig. 1). Recent geochemical investiga-tions reveal many PIA basalts in the Greater Antilles, including theTéneme Formation in Eastern Cuba (Proenza et al., 2006; Marchesiet al., 2007), and the Los Ranchos (Escuder-Viruete et al., 2006),Maimón (Lewis et al., 2000, 2002) and Amina (Escuder-Viruete et al.,2007b) Formations in Hispaniola, as well as some Water Islandbasalts, are regionally comparable low-Ti island-arc tholeiites (IAT)and boninites. Taken together, the timing and geochemical character-istics in the PIA suite suggest a supra-subduction zone setting duringthe earliest stages of the Aptian to Lower Albian Caribbean island arcdevelopment (Escuder-Viruete et al., 2006). In Hispaniola, the HatilloFormation, a massive reef limestone of upper Lower Albian age(Myczynski and Iturralde-Vinent, 2005), unconformably overlies theLos Ranchos Formation.

2.2. The geology of Central Hispaniola

Located on the northern margin of the Caribbean plate, thetectonic collage of Hispaniola results from the WSW to SW-directedoblique-convergence of the continental margin of the North Americanplate with the Greater Antilles island-arc system, which began inCretaceous and continues today. The arc-related rocks are regionallyoverlain by Upper Eocene to Holocene siliciclastic and carbonatesedimentary rocks that post-date island-arc activity, and record theoblique arc-continent collision in the north, as well as the activesubduction along the southern Hispaniola margin (Mann, 1999).Central Hispaniola is a composite of oceanic derived units bound bythe left-lateral strike-slip Hispaniola and San José–Restauración faultzones (Fig. 1). Accreted units mainly include serpentinized LomaCaribe peridotites, MORB-type gabbros and basalts, Late Jurassic deep-marine sediments, volcanic units related to Caribbean–Colombianoceanic plateau (CCOP; e.g. the Duarte Complex; Lapierre et al., 1997;Escuder-Viruete et al., 2007c), and Late Cretaceous arc-relatedigneous and sedimentary rocks (Lewis et al., 2002). These units arevariably deformed and metamorphosed to prenhite–pumpellyte,greenschist and amphibolite facies, but the textures of the protolithsare often preserved.

In the study area (Fig. 2), the macrostructure is characterized byseveral main NNW–SSE toWNW–ESE trending fault zones that bounddifferent crustal domains or tectonic blocks, e.g. Hispaniola (HFZ),Hato Mayor (HMFZ) and Bonao–La Guácara (BGFZ) fault zones. To thenorth of the HFZ, the Maimón Formation forms a NW-trending belt ofschists separating the Los Ranchos Formation, the Hatillo limestone,the Late Cretaceous Las Lagunas Formation and, locally, the Paleocene–Eocene sedimentary rocks of the Don Juan Formation, from the LomaCaribe Peridotite. The belt consists mainly of sub-greenschist andgreenschist-facies metabasalt and metadacite/rhyolite, and minorintercalated carbonaceous schist, iron formation and marble. Devel-opment of penetrative foliation increases toward the contact with theHFZ, where the rocks are converted to mylonitic–phyllonitic schists(Draper et al., 1996). To the NW, and in a similar structural position,the mafic and felsic Amina schists occur under the neogene sedimentsof the Cibao Basin (Fig. 1). On the basis of geochemical and Sr–Ndisotopic data, Escuder-Viruete et al. (2007b) argue that the mafic andfelsic schists of the Amina and Maimón Formations are foliated andmetamorphosed equivalents of the Los Ranchos Formation volcanics.

To the south of the HFZ, Central Hispaniola domain is also boundedby theHatoMayor fault zone, and comprises the LomaCaribe Peridotite,several related gabbro and dolerite bodies, the Río Verde Complex, andthe Peralvillo Sur Formation. Due to the fact that the block is composedof a peridotite basement intruded and/or covered by volcanic maficrocks, it has been considered tobeanophiolite (Lewis et al., 2002, 2006).The Loma Caribe Peridotite is mainly composed of spinel harzburgite,but clinopyroxene-rich harzburgite, dunite, lherzolite and small bodiesof podiform chromitites also occur (Lewis et al., 2006). The peridotites

Fig. 1. (a) Map of the northeastern Caribbean plate margin. Box shows location of the study area. (b) Schematic geological map of Central, Septentrional and Eastern Cordilleras inHispaniola. SFZ, Septentrional fault zone; HFZ, Hispaniola fault zone; BGFZ, Bonao–La Guácara fault zone; SJRFZ, San José–Restauración fault zone; EPGFZ, Enriquillo–Plantain Gardenfault zone. Box shows location of the Fig. 2.

170 J. Escuder-Viruete et al. / Lithos 114 (2010) 168–185

are typically extensively serpentinized and variably sheared, in par-ticular toward the upper structural levels. The overlying rocks consist ofhundred-meter-sized bodies of modal layered and foliated gabbro thatpass structurally upward into massive, isotropic gabbro. Individualdolerite dykes and sills intrude serpentinized peridotites and gabbroicrocks, showing chilled margins. They become more abundant upwards

in the sequence and to the NE. The Peralvillo Sur Formation forms anarrow belt immediately northeast of the Loma Caribe Peridotite(Fig. 2). It is composed of a 1500–2300 m-thick basaltic sequence ofmassive flows and pillow lavas that hostmassive sulfide deposits, and isoverlain by ∼1000 m of volcaniclastic sediments, tuffaceous mudstoneand Campanian radiolarian cherts (Lewis et al., 2002). South of the

Fig. 2. Schematic geological map of the Bonao 1:100,000 quadrangle and A–A' geological cross section, showing the stratigraphic and structural relationships of the Río Verde Complex. HFZ, Hispaniola fault zone; HMFZ, HatoMayor fault zone;and HT, Hatillo thrust. Stars show locations of samples for U–Pb and Ar–Ar geochronology and obtained ages, as well as some other relevant regional data (Lewis et al., 2002; Escuder-Viruete et al., 2007a and unpublished).

171J.Escuder-V

irueteet

al./Lithos

114(2010)

168–185


HMFZ, the Lower Cretaceous Duarte Complex is intruded by the ArroyoCaña batholith, the Late Cretaceous foliated Hbl-tonalites and theMiddle Campanian to Maastrichtian Siete Cabezas Formation.

3. Geology of the Río Verde Complex

The Río Verde Complex forms a NW-trending belt, of 4–5 kmwidth and 25 km length, with a strongly deformed contact against theLoma Caribe Peridotite. Internally, it consists of several imbricatedthin, but laterally extensive, NW-trending slices of mafic igneousrocks, subordinate sedimentary rocks and metamorphic derivatives.Felsic volcanic rocks are absent. These units are variably deformed andmetamorphosed to prenhite–pumpellyte, greenschist and low-Pamphibolite facies conditions. In the lower structural levels and tothe SW, it is composed of a 1500–2500 m-thick basaltic sequence ofmassive flows that host minor massive sulfide deposits, and isoverlain by ∼1000 m of mafic tuffs, volcaniclastic sediments,tuffaceous mudstone and green cherts. Upwards in the structuralsequence and to the NE an increase in deformation occurs and rocksare intensely sheared and transformed into fine-grained actinolite,epidote, chlorite, and white mica-bearing mafic schists to medium-and coarse-grained foliated amphibolites (Fig. 3b). However, gabbroicand doleritic textures such as coarse-grained, intersectal to subophitic

Fig. 3. Río Verde Complex rocks at Balneario Ledesma outcrop. (a) Gabbros andmetagabbros (108±20 Ma; Sm–Nd whole rock isochron) in an undeformed meter-scale boudin surrounded by foliated amphibolites. (b) Syn- to late-kinematic intrusionof a dolerite dyke in the amphibolites with a 110 Ma old S–L fabric (Ar–Ar in Hbl).Amphibolites and dolerite are similar BABB-like magmas and suggest coeval intrusionand deformation of Río Verde Complex magmas.

intergrowths of clinopyroxene and plagioclase have been preserved inlow strain pods (Fig. 3a). In the uppermost structural levels, the mainstructural elements in the amphibolites are a synmetamorphicfoliation (S) and mineral or stretching lineation (L). S is defined bythe planar alignment of hornblende and plagioclase prismatic grainsand, locally, by alternating Hbl-rich and Pl-rich segregations; L iscommonly defined by elongate Hbl nematoblasts. Regionally, S planeshave a consistently NW- toWNW-trend and dip a low to high-angle tothe NE. Syn- to late-kinematic dolerite dykes and Ep±Qtz±Cal veinsoccur throughout the Río Verde Complex, particularly in the upperstructural levels. Dolerite dykes can be traced into high-shear straindomains, where they are rotated subparallel to the regional foliationin the amphibolites and transformed into L–S mylonitic tectonites(Fig. 3b). Field relations therefore indicate that deformation andmetamorphism of the Río Verde Complex protoliths was in part coevalwith the syn-kinematic emplacement of the dolerite magmas andhydrothermal activity.

4. Geochronology

Map in Fig. 2 shows the sample locations. Analytical proceduresare in Appendix 1 and results are reported in Appendices 2 and 3. Allages are quoted at the 2σ level of uncertainty.

4.1. U–Pb samples

The selected U–Pb sample was a clinopyroxene+plagioclasefoliated gabbro (sample 6JE93A) collected in the core of a texturallyzoned sill ∼10 m-thick, intruded in the serpentinized Loma CaribePeridotite at Loma Peguera, Falcondo plant, Bonao. Typically, gabbroshave a magmatic foliation in the coarse-grained core of the sill thatgrades to a strong magmatic to solid state foliation in the fine-grainedrim, which is subparallel to the intrusive contact and the foliation inthe enclosing serpentinites. The sample has MORB geochemicalcharacteristics with a weak subduction signature (Section 5.3.,geochemistry). Only a few zircon grains were recovered from thesample; they were clear, pale pink to colourless, stubby to equantprisms, with aspect ratios of ∼1.5–2.0. Of these, two fractions (onesingle grain and one two grain fraction) yielded concordant, over-lapping and precise results (Fig. 4) that give a Concordia age (Ludwig,

Fig. 4. Concordia diagrams for microgabbro sill intrusive at Loma Peguera in the LomaCaribe serpentinized peridotite (6JE93A). U–Pb procedures and analytical data are inthe Appendices 1 and 2. See text for discussion.


2003) of 125.4±0.4Ma, which is interpreted as the crystallization ageof the gabbro. One other analysed grain gave overlapping, but veryimprecise results that do not affect the calculated age and two otherprocessed grains were not successfully analysed. The attempts ofdating the Río Verde Complex mafic protoliths by U–Pb method wereunsuccessful due to the absence of zircons.

4.2. 40Ar/39Ar samples

Amphibolites of the Río Verde Complex with a penetrative S–Lfabric were selected for dating by 40Ar/39Ar method (Fig. 5). Samplesshow a strongmineral lineation defined by 0.5–4mm long hornblendenematoblasts consistent with the simultaneity of ductile deformationand low-P amphibolite facies metamorphism. Sample 6JE34B is a

Fig. 5. The 40Ar/39Ar spectrum of hornblende from amphibolites of the Río VerdeComplex. The plateau ages were calculated following techniques described in Appendix1. A summary of 40Ar–39Ar incremental heating experiments is in Appendix 3. See textfor discussion.

blastomylonitic S–L amphibolite collected in the upper structurallevels of the complex at Balneario Ledesma outcrop. The protolith islocally preserved in low-strain domains surrounded by an S–C fabricdeveloped in the amphibolites (Fig. 3a), and consists of isotropicgabbrowithMORBgeochemical characteristics and aweak subductionsignature. The obtained hornblende plateau age is 110.3±1.4 Ma(MSWD=0.36) for five steps (7–11) and 70.2% of the 39Ar released.The inverse isochron age (MSWD=0.29) is 107±27 Ma. Sample6JE34D is an amphibolite with a strong S–L fabric also from theBalneario Ledesma. Mafic protoliths are also coarse-grained MORB-like tholeiitic gabbros. The obtained hornblende plateau age is 110.7±1.6 Ma (MSWD=0.33) for five steps (6–10) and 73.2% of the 39Arreleased. The inverse isochron age is 111±15 Ma (MSWD=0.34).Sample 2JE38 is a medium to coarse-grained amphibolite with afoliation defined by alternating Hbl-rich and Pl-rich bands. It wascollected near the tectonic contact with the Loma Caribe Peridotite inthe unpaved road to Río Verde town. The obtained hornblende plateauage is 118.6±1.3Ma (MSWD=0.44) for four steps (4–7) and 76.8% ofthe 39Ar released. The inverse isochron age for the same plateau stepsis 119.2±5.9 Ma (MSWD=0.35). For the six high temperature steps(4–9), the obtained inverse isochron age of 113.2±8.4 Ma(MSWD=1.8) is younger but within error of the original plateau.

4.3. Interpretation

Fig. 6 includes the U–Pb and Ar–Ar ages obtained for this study andother relevant regional data, which permits us to constrain the originand cooling history of the Río Verde Complex and to establishcorrelations with coeval units in Hispaniola. Two points are related inFig. 6. (1) The U–Pb 125.4±0.4 Ma age of the gabbro sill is the oldestto date obtained in the Central Cordillera and suggests that tholeiiticmagmas with a subduction-related signature are as old as thelowermost Aptian. (2) The Ar–Ar plateau ages obtained in theamphibolites indicates metamorphic thermal peak, ductile deforma-tion and cooling of the complex between 120 and 110 Ma, due to thepeak temperatures of 635–562 °C obtained from Hbl-Pl thermo-barometry and the slightly lower closure temperature of hornblende(525–450 °C). Thus, field and geochronological data supports thesynchronicity of the MORB-like magmatism with a subductionsignature and the syn-metamorphic deformation of the complex, atleast during the 120–110 Ma interval. This interpretation is consistentwith the imprecise but within error whole-rock Sm/Nd isochron ageof 108±20 Ma (MSWD=0.54; [143Nd/144Nd]i=0.512834), obtainedfrom seven samples of amphibolites and metabasalts of the Río VerdeComplex (Escuder–Viruete et al., unpublished). The dated gabbro sillis likely to belong to the same tholeiitic suite or to a different slightlyolder suite with similar geochemical characteristics.

The range of Ar–Ar plateau ages of the Río Verde Complexamphibolites are coeval, within error, to the porphyritic dacite/rhyolite flows of the Los Ranchos Formation, and the geneticallyrelated gabbros, diorites and the hornblende-bearing tonalites of theEastern Cordillera and Cotuí area batholiths (Fig. 6; data from Kesleret al., 2005; Escuder-Viruete et al., 2006). These results allow us toestablish the arc-related felsic volcanism of the Los RanchosFormation at 118–110 Ma (Late Aptian–Early Albian), and that thisvolcanism was coeval with the ductile deformation and the lastbatches of tholeiitic magmas of the Río Verde Complex, recorded bythe syn- to late-kinematic dolerite dikes. Also, these ages areconsistent with the late Lower Albian age of the unconformablyoverlying Hatillo Limestone (∼107–105Ma; Myczynski and Iturralde-Vinent, 2005). In summary, the data presented indicates that the RíoVerde Complex mafic magmas were in part coeval with volcanic rocksof the Los Ranchos Formation, i.e. they are part of the LowerCretaceous Caribbean island-arc–back-arc system. Note that, southof the HFZ, the Duarte Complex records Lower Cretaceous mantleplume magmatism without subduction influences.

Fig. 6. (a) Summary of geochronological ages for the Los Ranchos Formation and intrusive Hbl-bearing tonalite batholiths in the Eastern Cordillera. Sources; a, Kesler et al. (2005); b,Escuder-Viruete et al. (2006); c, this work; and d, Myczynski and Iturralde-Vinent (2005). Rectangles are the error bars (in 2σ). Time scale from Gradstein et al. (2004). See text fordiscussion.


5. Geochemistry

5.1. Analytical methods

Samples were powdered in an agate mill, and analysed for majoroxides and trace elements by inductively-coupled plasma-massspectrometry (ICP-MS). This analytical work was done at ACMEAnalytical Laboratories Ltd in Vancouver and results reported inTable 1, as well as details of analytical accuracy and reproducibility inAppendix 1. For major elements the detection limits are in general

Table 1Major and trace element data of representative rocks from the Río Verde Complex, Amina Formation and mafic intrusives in the Loma Caribe Peridotite.

Unit RVC RVC RVC RVC RVC RVC RVC RVC RVC RVC RVC

X (UTM) 388982 377250 377800 379148 379148 378169 377250 378174 393139 393139 393139

Y (UTM) 2070035 2080100 2077050 2078379 2078379 2077480 2080100 2077479 2064916 2064916 2064916

Rocka AMPH AMPH MBAS AMPH AMPH MBAS AMPH AMPH DOL AMPH AMPH

Sample 6JE34D 2JE31 2JE33 2JE38 7JE38 2JE34 2JE31B 2JE35 2JE112 6JE113 2JE114

wt.%SiO2 48.49 50.64 50.88 51.58 53.13 51.35 50.41 49.79 50.66 52.91 53.46TiO2 1.08 0.73 0.73 1.18 1.07 1.15 1.57 1.38 0.99 1.49 1.5Al2O3 12.22 16.46 15.59 15.3 14.97 15.39 14.29 14.34 15.78 14.8 14.89Fe2O3 10.66 8.2 8.8 10.02 9.19 10.5 11.79 11.71 9.5 11.22 11.21MgO 11.74 7.29 7.46 6.44 6.15 6.54 6.48 6.43 7.55 5.35 5.08CaO 10.87 11.21 11.3 10.56 9.59 9.93 9.95 11.08 11.08 8.55 8.55Na2O 1.85 2.72 2.39 3.02 3.34 3.52 3.28 3.03 2.79 3.47 3.77K2O 0.18 0.53 0.28 0.36 0.38 0.31 0.33 0.15 0.4 0.7 0.39P2O5 0.09 0.06 0.06 0.1 0.097 0.1 0.14 0.12 0.07 0.12 0.12MnO 0.18 0.13 0.15 0.17 0.15 0.17 0.2 0.18 0.16 0.17 0.17Cr2O3 0.07 0.04 0.04 0.03 0.024 0.005 0.02 0.02 0.04 0.01 0.02LOI 1.55 1.95 2.4 1.3 1.7 1.3 1.75 1.45 1.3 1.25 1.1Total 99.0 100.0 100.1 100.1 99.8 100.3 100.2 99.7 100.3 100.0 100.3Mg#b 69 64 63 56 57 55 52 52 61 49 47Cr 493 266 259 201 – 79 147 134 284 93 157Co 55 36 37 35 62.2 38 41 38 38 35 33Ni 227 90 92 76 31 51 50 56 95 32 38V 292 242 278 310 259 325 367 423 298 389 402Rb 0.3 1.2 0.5 1.3 6.2 1.1 1.0 0.2 1.3 3.6 1.5Ba 10 44 58 78 42 37 46 39 25 59 44Th 0.1 0.1 0.06 0.2 0.05 0.2 0.1 0.1 0.05 0.15 0.2Nb 1.1 1.0 0.65 1.0 1.0 1.1 0.9 1.0 1.1 1.0 2.0Ta 0.25 0.25 0.25 0.25 0.3 0.25 0.25 0.25 0.25 0.25 0.25La 2.44 1.9 1.39 2.8 2.5 2.6 3.4 2.7 2.1 3.3 3.6Ce 8.27 4.9 4.59 8.3 7.5 7.5 10.2 8.2 5.6 9.9 10.1Pb 0.6 0.4 0.8 1.0 0.5 0.9 0.2 0.3 0.8 0.6 1.0Pr 1.40 0.94 0.81 1.57 1.33 1.44 1.94 1.57 1.12 1.84 1.89Sr 40.0 86.5 75.6 89.4 140.8 68.6 78.7 69.9 82.2 91.1 52.7Nd 7.8 4.3 4.6 6.5 7.4 6.5 8.9 6.1 5.1 8.4 8.4Sm 2.6 1.5 1.6 2.2 2.4 2.1 3.0 2.0 1.8 2.8 2.6Zr 18.3 42.0 37.1 65.0 61.4 61.0 87.0 64.0 50.0 76.0 77.0Hf 0.7 1.0 1.2 2.0 2.3 2.0 4.0 2.0 2.0 3.0 3.0Eu 0.98 0.67 0.66 1.08 0.93 1.05 1.36 1.09 0.9 1.18 1.25Gd 3.50 2.59 2.32 4.03 3.76 3.74 5.05 4.39 3.17 4.74 4.46Tb 0.67 0.43 0.45 0.76 0.67 0.68 0.99 0.83 0.58 0.84 0.83Dy 4.36 2.87 3.07 4.99 4.49 4.51 6.33 5.20 3.85 5.44 5.33Y 23.8 17.0 16.5 25.0 24.6 22.0 32.0 26.0 20.0 28.0 29.0Ho 0.92 0.67 0.65 1.11 0.94 0.98 1.41 1.17 0.82 1.19 1.20Er 2.75 1.77 1.94 3.16 2.68 2.91 3.91 3.41 2.64 3.45 3.49Tm 0.45 0.29 0.29 0.47 0.41 0.42 0.62 0.47 0.37 0.5 0.51Yb 2.53 1.90 1.87 3.00 2.45 3.00 4.00 3.30 2.40 3.40 3.50Lu 0.39 0.28 0.28 0.45 0.38 0.44 0.58 0.53 0.37 0.52 0.49

Unit LCP LCP LCP LCP LCP AmF AmF AmF AmF AmF AmF

X (UTM) 360773 358500 358500 358500 335187 244368 242263 280317 243458 244368 276851

Y (UTM) 2090364 2090500 2090500 2090500 2120924 2161685 2163095 2149186 2164257 2161685 2146790

Rocka GAB GAB GAB GAB DIQ MSCH MSCH MSCH MSCH MSCH MSCH

Sample 6JE92B 6JE93A 6JE93B 6JE94 6JE99 FC9068B MJ9122 FC9110 MJ9049 MJ9068 FC9106

wt.%SiO2 44.36 51.01 50.07 49.48 51.3 47.89 50.58 48.1 49.85 55.88 52.9TiO2 1.48 1.37 1.94 1.0 0.85 1.05 0.95 0.4 0.92 0.74 0.17Al2O3 15.45 15.45 14.93 15.97 14.63 16.89 16.17 18.45 17.38 16.75 12.44Fe2O3 11.25 11.11 12.82 9.61 9.62 9.04 10.47 9.15 11.85 8.92 6.47MgO 7.87 5.74 5.25 8.15 8.49 8.24 5.08 4.44 4.72 3.11 7.26CaO 11.26 8.73 8.12 9.75 8.56 11.21 8.84 13.1 5.98 5.33 9.08Na2O 3.04 4.58 4.57 2.97 3.72 2.82 2.61 0.74 5.06 5.44 5.17K2O 0.11 0.28 0.31 0.28 0.41 0.17 1.73 0.05 0.09 0.38 0.36P2O5 0.14 0.11 0.17 0.04 0.08 0.14 0.31 0.04 0.1 0.08 0.02MnO 0.18 0.18 0.2 0.16 0.17 0.15 0.17 0.15 0.21 0.15 0.16Cr2O3 0.024 0.006 0.007 0.046 0.047 0.031 0.005 0.015 0.001 0.005 0.051LOI 4.7 1.4 1.6 2.3 2.0 2.1 2.7 5.2 3.4 2.7 5.6Total 99.9 100.0 100.0 99.8 99.9 99.6 99.6 99.8 99.6 99.5 99.7Mg#b 58 51 45 63 64 64 49 49 44 41 69Cr 164 41 48 315 322 212 34 103 7 34 349Co 58 52 58 42 48 45 34 35 36 20 31

(continued on next page)


Table 1 (continued)

Unit RVC RVC RVC RVC RVC RVC RVC RVC RVC RVC RVC

X (UTM) 388982 377250 377800 379148 379148 378169 377250 378174 393139 393139 393139

Y (UTM) 2070035 2080100 2077050 2078379 2078379 2077480 2080100 2077479 2064916 2064916 2064916

Rocka AMPH AMPH MBAS AMPH AMPH MBAS AMPH AMPH DOL AMPH AMPH

Sample 6JE34D 2JE31 2JE33 2JE38 7JE38 2JE34 2JE31B 2JE35 2JE112 6JE113 2JE114

wt.%Ni 24 271 103 817 29 56 15 12 10 7 36V 326 359 456 258 300 193 294 261 362 313 153Rb 1.3 2.5 2.6 3.9 5.1 4.6 39.3

Fig. 7. Nb/Y versus Zr/TiO2 diagram (Winchester and Floyd, 1977) for the diverse Lower Cretaceous igneous rocks in Hispaniola.

Fig. 8. Plot TiO2 versus MgO for the diverse geochemical groups of Lower Cretaceousigneous rocks in Hispaniola. NVTZ, CG and SR fields are Northern Volcano–TectonicZone, Central Graben and Spreading ridge fields of the Mariana Arc–Trough systemfrom Gribble et al. (1998), which are shown for comparisons with a modern analog. LosRanchos and Amina Formation data are from Escuder-Viruete et al. (2006) and thiswork. The Maimón Formation field includes data from Lewis et al. (2000, 2002). Alsoindicated are 5% fractional crystallization vectors for olivine (Ol), clinopyroxene (Cpx),and plagioclase (Pl), determined from the average Río Verde Complex composition.


the subduction environment (Pearce and Peate, 1995), and the TiO2concentrations should therefore provide an indicator of the extent ofsource depletion, taking into account the Fe–Ti oxides fractionation.Several points are shown in this figure. (1) The trend of increasingTiO2 with decreasing MgO in the Río Verde Complex samples is notseen in the PIA suite, which shows a low-Ti trend. (2) The mafic sillsand dykes of the Loma Caribe Peridotite have similar TiO2 contents tothe Río Verde Complex samples and both are significantly TiO2enriched relative to the PIA suite, which show a progressive TiO2increase from the boninites, to low-Ti IAT to normal IAT. (3) The RíoVerde Complex basalts, dolerites and amphibolites have similar TiO2contents to the basalts and basaltic andesites from the Central Gravenand Spreading Ridge of the Northern Mariana Trough (Gribble et al.,1998), but are less fractionated than the Northern Volcano-TectonicZone of the rifted Mariana Arc. Therefore, the diverse TiO2 content inthe PIA suite and Río Verde Complex magmas suggests differentCaribbean mantle sources.

Comparisons are also made through patterns in normal mid-oceanridge basalt (N-MORB) normalized trace elements diagrams (Fig. 9),which are all characterized by significant enrichment in LILE (Rb, Ba,Th, U, Pb and K) and LREE relative to the HFSE (Nb, Ta, Zr, Hf, Ti and Y)and HREE. Río Verde Complex samples display a slight LREE depletionor enrichment and a flat HREE pattern. The obtained values in theprimitive mantle normalized ratios (La/Nd)N=0.6–0.9 and (Sm/Yb)N=0.98–1.1 are characteristic of N-MORB (e.g. Su and Langmuir,2003). Relative to N-MORB, however, these rocks have Nb–Tanegative anomalies and higher abundances of LILE such as Rb, Ba, Kand Pb. Such anomalies in intra-oceanic settings are widely inter-preted to reflect supra-subduction zonemagmatism, involvingmantlewedge sources that have been contaminated by mass transfer (meltsor fluids) from the subducting slab (Pearce and Peate, 1995). In thearc-related Los Ranchos Formation, these aforementioned geochem-ical signatures increase from the boninites through the low-Ti IATs tothe IAT (Escuder-Viruete et al., 2006). The IAT have almost flat (N-MORB-like) HFSE profiles, whereas the boninites show the greatestdegrees of depletion of these elements. In the Río Verde Complexmetabasalts and amphibolites, the trace element patterns are sub-parallel to those of the IAT of the Amina and Los Ranchos Formations,although these volcanics are more enriched in the subduction mobileelements Th, LILE and LREE (Fig. 9b–c). A weak subduction signatureis also established by Nb/Th ratio values of 5–11.5 in Fig. 8b, whereas

Fig. 9. MORB-normalized multi-element plots for: (a) amphibolites of the Río Verde Complex; (b) basalts and dolerites of the Río Verde Complex and metavolcanic rocks of AminaFormation; (c) volcanic rocks of the Los Ranchos Formation (Escuder-Viruete et al., 2006); and (d) mafic rocks intruded in the Loma Caribe Peridotite (Table 1). MORB-normalizingvalues are from Sun and McDonough (1989).


PIA suite samples generally present Nb/Th

Fig. 10. (a) Initial Sr–Nd isotopes ratios (i=115 Ma) for the different geochemicalgroups of Lower Cretaceous igneous rocks in Hispaniola. The fields for the DuarteComplex, the CCOP (except Gorgona) and Caribbean island-arc lavas fromNortheasternand Central Puerto Rico, are taken from Escuder-Viruete et al. (2007a), Hastie et al.(2008; and references herein), Hauff et al. (2000), Jolly et al. (2001, 2006, 2007) andThompson et al. (2004). The MORB-OIB array is defined by the subduction-unmodifiedlavas from the East Pacific Ridge (data from PETDB, 2007; and references herein).Depleted MORB mantle (DMM) Sr–Nd isotopic compositions are taken from Su andLangmuir (2003): DMM average for MORBs far from plumes; D-DMM is 2σ depletedand E-DMM is 2σ enriched over the average. CAM is Cretaceous Atlantic MORB (Janneyand Castillo, 2001). Fields and mantle components are not age corrected to 115 Ma. (b)Caribbean island-arc field is subparallel to a calculated mixing line between pelagicsediments and representative arc basalt taken from Jolly et al. (2001). The Sr–Ndisotopic data for Río Verde Complex, Amina and Los Ranchos Formations suggest aminor subducted sedimentary component (70 Ma from Aptian to the Eocene (data from Jollyet al., 2001, 2006, 2007). The Caribbean island-arc lavas are displacedfrom the MORB-OIB array to higher concentrations of the subduction-mobile element Th.

In the Zr/Yb versus Nb/Yb plot (Fig. 11), samples of Los Ranchos,Amina and Maimón Formations are collectively located near averageN-MORB and extend along the depleted part of the Caribbean island-arc trend. Therefore, for these rocks both Zr and Nb are not present insignificant concentrations in the subduction component (Pearce et al.,1995). The plot shows that samples from the Río Verde Complex aregenerally similar to the PIA suite in that they also have low Zr/Yb andNb/Yb ratios, but they have amore restricted composition. Themantlesource for all units is variably depleted relative to average N-MORBand interpreted to have experienced previous partial melt extraction,and hence depletion in incompatible elements (Pearce et al., 1995).Their low Nb/Yb ratios (and higher [εNd]i values) discard the influenceof a Caribbean plume component in the Lower Cretaceous Caribbeanisland-arc–back-arc system, which displace CCOP samples from theMORB-OIB array to higher Nb/Yb values in an opposite sense to vectorB in Fig. 11d.

Addition of a variable subduction component to a mantle sourceof constant composition results in a vertical trend on the diagrams ofthe Fig. 11, as Th is non-conservative and Nb and Yb are conservative

(vector A; Pearce et al., 1995). PIA suite samples follow this verticaltrend. Fig. 11c shows that subduction vector A extends vertically fromthe Caribbean MORB-OIB array, with the subduction contributionestimated by contour lines drawn parallel to the array. Fig. 10d revealsthat the subduction contributions for Th range up to 90% for LosRanchos, Amina and Maimón Formations, being generally lower(

Fig. 11. Plots of (a, b) Zr/Yb and (c, d) Th/Yb versusNb/Yb for the Lower Cretaceous igneous rocks in Hispaniola. The Caribbean island-arc trend is represented by the Aptian to Eocenevolcanic rocks of Puerto Rico (data from Jolly et al., 2001, 2006, 2007). CaribbeanMORB-OIB array is defined by the subduction-unmodified lavas from the East Pacific Ridge (data fromSu and Langmuir, 2003, PETDB, 2007; and references herein) and completed by samples from the Late Cretaceous Caribbean–Colombian oceanic plateau (Hauff et al., 2000; Kerr et al.,1997, 2002; Sinton et al., 1998; Lapierre et al., 1999, 2000). The Caribbean plume enriched component probably increases inmagnitudewith proximity to the plume. N-MORB, E-MORBand OIB values are from Sun andMcDonough (1989). In the plot, there are three principal types of trend (vector), described in detail by Pearce et al. (1995): A= variable subductioncomponent; B = variably enriched mantle wedge; C = variable melt extraction. See text for explanation.


depletion is calculated after 5, 10, 15, 20, and 25% prior fractionalmelting“events” (referred to as RMM5 to RMM25, respectively, where RMM isresidual MORB mantle), with appropriate adjustment of the phasemineralogy during the calculated melting steps; 1% porosity is assumed.Trace element compositions of the melts produced, by further fractionalmelting and pooling of melts of the RMM5 to RMM25 sourcecompositions, are then calculated for 5, 10, 15 and 25% remelting (i.e.second stage melts), believed to simulate the range of Caribbeansubduction system melt zones.

Tomodel the possible effects of subduction input, the composition ofa subduction-derived “H2O-rich component” following Stolper andNewman (1994) is used, due to the uncertainty in the composition ofmost fluid-mobile elements in the original Caribbean magmas. Thisimplies modifying the RMM5 to RMM25 source compositions byaddition of 0.001, 0.005, and 0.01 weight fractions of this H2O-richcomponent. The second stagemelting calculations are then repeated for5 and 15% melting, as before. The resulting curves (Fig. 12) forsubduction modified source compositions are believed to approximatethe effects of remelting of mantle wedge which has been modified byprior, variable melt extraction (i.e. source depletion) and then selectivesubduction-derived enrichment. To minimize the effects of fractionalcrystallization and crystal accumulation, a MgO value of 9 wt.% waschosen for parental magmas and the theoretical trace element contentof each sample at this MgO value was calculated following themethodology of Pearce and Parkinson (1993). The modeled meltcompositions for different percentageof partialmelting, different sourcecompositions, and different subduction enrichment are plotted in

Fig. 12. These plots allow us to distinguish more conservative elements(Y and Ti) from non-conservative elements (Sm and Ba), in which Yb istreated as fully conservative (Pearce and Parkinson, 1993).

6.1.2. Source characterizationComparison of the Caribbean island-arc–back-arc system compo-

sitions, with the calculated melting curves suggests that concentra-tions of Ti, Y and Yb depend on the degree of source depletion and arelittle modified by subduction input (Fig. 12a–b). This allowsevaluating the source of the three main Caribbean magma groups:BABB of the Río Verde Complex and mafic sills intruded in the LomaCaribe Peridotite; IAT; and low-Ti IAT and boninites of the LosRanchos, Amina, and Maimón Formations. BABB group of magmas(Yb9=1.5–3.2; Ti9=3700–7200; Y9=15–30; Sm9=1.2–2.8; Zr/Ba=0.6–2.6) requires a depleted shallow spinel lherzolite mantle(FMM) affected by

Fig. 12. Calculated melt composition for 1, 5, 10, 15 and 25% remelting of previously depleted model mantle wedge compositions (corresponding to FMM to RMM25 compositions, asdefined in the text; numbers along curves are percentage of prior melt extraction) for: Yb versus (a) Y, (b) Ti (both unaffected by subduction), (c) Sm (minor subduction effect), and(d) Zr/Ba (high subduction effect). These curves are compared, in each plot, with the normalized (MgO=9%) data, from selected compositions for Los Ranchos, Amina and MaimónFormations, Río Verde Complex, andmafic dykes and sills. In (c) and (d), calculated effects of addition of 0.001 wt fractions of “H2O-rich component” to the variously depleted modelmantle wedge sources, followed by 5 and 15% remelting, are shown (discontinuous curves). FMM and RMM are fertile and residual MORB mantle, respectively. See text forexplanation.


An increase in subduction component is suggested when variablynon-conservative elements are plotted against each other. Fig. 12c–dshow varying degrees of departure from the curves of the calculatedmelts. Sm is an example of an element that shows moderatelydifferent values to the calculated melts whereas the trend for Ba(expressed as Zr/Ba) departs markedly from the calculated depletiontrends (Fig. 12c–d). In all cases, however, these diverging trends canbe broadly matched with the calculated melt trends from the“subduction modified” sources containing ∼0.001 weight fraction ofthe modeled H2O-rich component. Comparison of the Caribbeanisland-arc–back-arc system compositions, with the calculated meltingcurves suggests a higher subduction component in IAT and low-Ti IATand boninites groups than in BABB group, particularly for Sm. As Ba ismobile in aqueous fluids (Elliott et al., 1997), the generally lowervalues of the Zr/Ba ratio obtained for the PIA group also suggest ahigher enrichment in fluid-mobile elements than in BABB group.However, the results obtained for the Ba should be considered asqualitative, since this element could be also mobilized during the latealteration and metamorphism.

6.1.3. Isotope-trace element resultsTo investigatepossible balances betweendiffering subduction inputs

(slab derived components) and differing degrees of mantle sourcedepletion, Nd isotopic data have also been modeled. Two endmemberswere chosen (Appendix 3): the mantle wedge, based on the averageisotopic compositions of AEPR (average Eastern Pacific Ridge MORB, ormantle wedge unmodified by subduction components); and themodeled subduction flux composition (SF). Abundance of Nd follow

the Stolper and Newman, (1994) estimates for the “H2O-rich compo-nent” (as used above), and weight fractions of 0.001, 0.005, and 0.01 ofthis component are again added to the modeled mantle wedge sources(FMM, RMM5 to RMM15), and second stage melt compositions arecalculated. Results are shown in Fig. 13, in which calculated Nd isotoperatios are plotted against Nd and Ti. These trends are comparedwith thenormalized element abundances (MgO=9%) and Nd isotopic compo-sition of different geochemical groups. Each plot shows the effects ofprogressive subduction input on the second stage melts derived fromeach variably depletedmantle source composition, and the dashed linesmark the combined trends of variable source depletion with super-imposed constant subduction input. The compositionally diverse groupsderived from different mantle sources can be illustrated by Ti, leastaffected by subduction input (Fig. 13b). As previously deduced fromtrace elementmodeling, the source of BABB groupmagmaswas relativeenriched compared to sources of the PIA groups, particularly for low-TiIAT and boninites. The subduction inputs can be evaluated in Fig. 13a,where observed melt trends follow a similar H2O-rich componentbetween 0.001 and 0.005 weight fractions, but where abundances stillreflect variations in source depletion composition. Melt modelingindicates that subduction input in BABB group were slightly lowerthan in PIA groups, particularly for IAT. As the LREE (and Th) are oftenenriched in clastic sediments but are not highlymobile influids (Stalderet al., 1998), a minor sediment addition in the low-Ti IAT and boninitegroups than in the IAT group is suggestedby their lowerNdcontents andNd isotopic ratio values. A lower sediment addition is also shown by thedecrease in the Th/Yb ratio values from IAT and low-Ti IAT and boninitesto BABB groups (Fig. 11d).

Fig. 13. Calculated isotopic and trace element melt compositions for 15% remelting ofpreviously depleted model mantle wedge compositions (FMM to RMM15), assumingzero, 0.001, 0.005, and 0.01 weight fraction of a “H2O-rich component” added to thesesources. The continuous lines show increasing weight fractions of this component tothe source, up to 0.01 from each given starting model mantle composition (FMM toRMM15). The discontinuous curves mark combined source depletion plus constantsubduction input to source trends. The calculated curves are comparedwith normalized(MgO=9%) data for Los Ranchos, Amina and Maimón Formations, and Río VerdeComplex. In all cases, the altered oceanic crust isotopic endmember is used. See text forexplanation.


In summary, the combined trace element and trace element-isotope modeling are consistent, and suggest that the coupledprocesses of mantle wedge depletion with input of a subductioncomponent (modeled between 0.001 and 0.005 weight fractionabundances of a H2O-rich component) can explain the geochemistryof the Caribbean island-arc–back-arc system magmas. The correla-tions between geochemical source depletion indicators (e.g. Yb, Y, Ti),together with the observed Nd isotopic composition variations alongeach geochemical groups, are inferred to result from a progressivelylower subduction flux into a mantle wedge which is progressively lessdepleted from the arc to the back-arc units. Also, Nd-isotope andincompatible trace element patterns are diverse in the mafic rocksgroups, but all are consistent with sources unrelated to a LowerCretaceous Caribbean mantle plume. Both can be considered as twosignificant conclusions that have important tectonic implications.

6.2. Tectonic implications

The Los Ranchos Formation has been proposed as a record of thevolcanic activity in the suprasubduction zone setting of the primitiveCaribbean island-arc (Escuder-Viruete et al., 2006). In this tectoniccontext, the data presented in thiswork imply: (1) Los Ranchos, Amina

and Maimón Formations are petrological and geochemical equiva-lents, form part of the same volcanic front, and include similarboninites, IAT and felsic volcanic rocks; (2) the protoliths of the RíoVerde Complex, exclusively of BABB-like mafic composition, wereextruded/intruded during arc rifting and the early stages of a back-arcbasin development; (3) the Río Verde Complex was deformed by aheterogeneous syn-metamorphic shearing at ∼110 Ma; (4) the latestbatches of the BABB-likemagmas are syn- to late-kinematic in relationto this low-P/low tomiddle-T deformation; (5) the spatial distributionof arc and back-arc related geological units in Hispaniola, in actual NEand SW positions, respectively, indicates a SW-directed subductionpolarity in the Lower Cretaceous; (6) a same subduction polarity canbe deduced from the progressively lower subduction flux into aprogressively less depleted mantle source of the PIA suite and the RíoVerde Complex; and (7) the shallow limestones of the HatilloFormation were deposited in the upper Lower Albian on top of theeroded arc.

In order to explain these observations, a model of proto-Caribbeanoceanic lithosphere subducted at least in the 120–110 Ma interval, isproposed as the cause of tectonic and magmatic variations in theLower Cretaceous Caribbean island-arc–back-arc system (Fig. 14),which is supported by the onset of SW-dipping subduction innorthern Hispaniola and in eastern Cuba at ∼120 Ma (Krebs et al.,2007; Lázaro et al., 2008). In this context, arc rifting and sea-floorspreading to form the Río Verde Complex protoliths occurred in theback-arc setting of this NE-facing primitive island-arc, built onto theNE edge of the Caribbean plate. This spatial configuration explains, onthe one hand, the existence of a back-arc area not affected by slab-derived geochemical components and, on the other hand, it precludesthe presence of a Caribbean plume component in the petrogenesis ofthe PIA magmas. However, this plume component is present in thepicrites and high-Mg basalts of the Lower Cretaceous Duarte Complex(Escuder-Viruete et al., 2007c), probably advected by lateral mantleflow of the CCOP source. Therefore, the Caribbean island-arc–back-arcsystem includes three different magma sources related to threedifferent mantle domains. From the volcanic front toward the back-arc (Fig. 14), these melt source regions are a suprasubduction mantlewedge, a back-arc spreading centre, and a deep mantle containinggarnet influenced by an enriched plume. These mantle domains wereoriginally separated by an undetermined distance and their structuraljuxtaposition took place later, during the closure of the back-arc basin,probably in the Middle Eocene arc–continent collision.

Finally, it remains to explain the relations between the Río VerdeComplex and the BABB-like magmas intruded/extruded in CentralHispaniola during the Late Cretaceous. Based on the Turonian–Campanian volcanic history and the geochemical composition of theirconstituent igneous rocks, the tectonic blocks that made up CentralHispaniola have been recently interpreted as remnants of extendedisland-arc and oceanic plateau, transitional and oceanic crust, whichformed part of a Loma Caribe back-arc basin (Escuder-Viruete et al.,2008). The data presented in this work suggest that the back-arcspreading system that formed the Río Verde Complex protoliths at∼120–110 Ma was not sufficiently separated from the volcanic front,and it was still affected by slab-derived geochemical components. Afteran interval of arc inactivity and erosion in the upper Lower Albian, theridge system propagated toward the NW into the actual CentralCordillera, rifting at ∼90 Ma the Albian to Turonian arc and openingduring the Santonian to Lower Campanian the Loma Caribe back-arcbasin. Later, the Central Hispaniola terrain was tectonically juxtaposedwith the Lower Cretaceous arc by arc-parallel, large-scale sinistralstrike-slip shearing along the Hato Viejo and Hispaniola fault zones.

7. Conclusions

Variations of trace elements parameters (Nb/Yb, Th/Yb, Zr/Yb, Zr/Ba, and normalized Ti, Sm, Y and Yb abundances) and Nd isotopic

Fig. 14. Schematic tectonomagmatic model for Upper Aptian–Lower Albian Caribbean island-arc–back arc system based on the spatial distribution of igneous rocks in Hispaniola. Themantle flow convective regimes beneath rifted arcs and evolving back-arc basins are inspired in Gribble et al. (1998) and Taylor andMartinez (2003). The SW-directedmotion of thesubducting proto-Caribbean slab drives corner flow advection in the mantle wedge. Water released by the downgoing slab promotes partial melting in the mantle above the solidus(heavy dashed lines), which is progressively depleted of a melt component toward the volcanic front. Melts rises and gave rise to extrusion of initially boninites and low-Ti IAT andsubsequently normal IAT (Escuder-Viruete et al., 2006). When arc extension commences, the lithosphere rifts near the rheologically weak volcanic front. Hydrated mantle isadvected upward into the stretching and thinning lithosphere, leading to high degrees of melting in the rift phase, and promotes the lower arc crust melting and development offelsic volcanism and tonalitic plutonism. With increasing extension a seafloor spreading centre is established near the volcanic front advecting highly hydrated mantle. Asconsequence, BABB-like Río Verde Complex magmas result in a SW position respect the volcanic front. Melts derived from a deeper Caribbean plume enriched source areincorporated by lateral flow from the SW and gave rise to the OIB-like off-ridge magmatism of the Duarte Complex, in the back-arc area located SW of the spreading system, which isnot affected by slab-derived geochemical components. The Loma La Monja volcano-plutonic assemblage represents a dismembered fragment of the Late Jurassic Pacific-derivedoceanic crust, in which Duarte Complex melts were intruded. The migration of this propagating back-arc rift system toward the NW produced arc-rifting and back-arc basindevelopment from ∼90 Ma in the Central Hispaniola domain (Escuder-Viruete et al., 2008). CCOP, Caribbean–Colombian oceanic plateau; SC, Septentrional Cordillera; EC, EasternCordillera; CC, Central Cordillera in Hispaniola. Age of eclogitic metamorphism in the Río San Juan high-P complex is from Krebs et al. (2007). See text for further explanation.


compositions are observed in the Aptian to Lower Albian maficigneous rocks throughout Hispaniola. These variations are systematicand establish gradients that reflect differences in the degree of mantlesource depletion and variations in the subduction flux. Across theCaribbean island-arc–back-arc system, a progressively lower subduc-tion flux into a progressively less depleted mantle source is recordedfrom arc related Los Ranchos, Amina and Maimón Formations, to therifted-arc to back-arc related Río Verde Complex and the maficintrusions of the Loma Caribe Peridotite. These gradients imply a SW-directed subduction polarity and are consistent with the cartographicdistribution of arc and back-arc geological units. By modeling thesimultaneous effects of source depletion and subduction input, thecalculated trace element and Nd isotope ratio curves for mantlemelting and magma sources reproduce the observed data trends fromarc to back-arc. Modeling suggests that HREE and Ti are least affectedby subduction input, with Sm showing minor modification, whereasBa has strong subduction input effects. Using the “H2O-rich compo-nent” model of Stolper and Newman (1994), levels of 0.001–0.005weight fractions are suggested to have been added to the arc sources.

The low Nb contents and high (εNd)i values in both arc and back-arcrelated mafic rocks imply the absence in the source of a significantLower Cretaceous plume enriched component.

Acknowledgements

The authors would like to thank John Lewis (George WashingtonUniversity), Gren Draper (Florida International University) andFrancisco Longo (Falconbridge Dominicana) for discussions on theigneous rocks in the Dominican Republic. We are also grateful tomanycolleagues of the IGME-BRGM team for their help and topicdiscussions. Dirección General de Minería of Dominican Governmentis also thanked for the support. Elisa Dietrich-Sainsaulieu is thankedfor her help with the Sr–Nd isotopic analyses at PCIGR. This workforms part of the MCYT projects BTE-2002-00326 and CGL2005-02162/BTE and also received aid from the cartographic project of theDominican Republic funded by the SYSMIN Program of the EuropeanUnion. Careful reviews from Dr. Andrew Kerr and two anonymousreviewers are much appreciated.


Appendix A. Supplementary data

Supplementary data associated with this article can be found, inthe online version, at doi:10.1016/j.lithos.2009.08.007.

References

Arculus, R.J., Powell, R., 1986. Source component mixing in the regions of arc magmageneration. Journal of Geophysical Research 91B, 5913–5926.

Bédard, J.H., 1999. Petrogenesis of boninites from the Betts Cove Ophiolite, Newfound-land, Canada: identification of subducted source components. Journal of Petrology40, 1853–1889.

Brenan, J.M., Shaw, H.F., Ryerson, F.J., Phinney, D.L., 1995. Mineral-aqueous fluidpartitioning of trace elements at 900 °C and 2.0 GPa: constraints on the traceelement chemistry of mantle and deep crustal fluids. Geochimica et CosmochimicaActa 59, 3331–3350.

Defant, M.J., Drummond, M.S., 1990. Derivation of some modern arc magmas bymelting of young subducted lithosphere. Nature 347, 662–665.

Donnelly, T.W., Beets, D., Carr, M.J., Jackson, T., Klaver, G., Lewis, J., Maury, R.,Schellenkens, H., Smith, A.L., Wadge, G., Westercamp, D., 1990. History and tectonicsetting of Caribbeanmagmatism. In: Dengo, G., Case, J. (Eds.), The Caribbean Region.Vol. H. The Geology of North America. Geological Society of America, pp. 339–374.

Draper, G., Lewis, J.F., 1991. Metamorphic belts in Central Española. In: Mann, P., Draper,G., Lewis, J.F. (Eds.), Geologic and Tectonic Development of the North America-Caribbean Plate Boundary in Española: Geological Society of America Special Paper,vol. 262, pp. 29–46.

Draper, G., Gutiérrez, G., Lewis, J.F., 1996. Thrust emplacement of the Españolaperidotite belt: orogenic expression of the Mid Cretaceous Caribbean arc polarityreversal. Geology 24 (12), 1143–1146.

Elliott, T., Plank, T., Zindler, A., White, W., Bourdon, B., 1997. Element transport fromslab to volcanic front at the Mariana arc. Journal of Geophysical Research 102,14,991–15,019.

Escuder-Viruete, J., Díaz de Neira, A., Hernáiz Huerta, P.P., Monthel, J., García Senz, J.,Joubert, M., Lopera, E., Ullrich, T., Friedman, R., Mortensen, J., Pérez-Estaún, A., 2006.Magmatic relationships and ages of Caribbean island-arc tholeiites, boninites andrelated felsic rocks, Dominican Republic. Lithos 90, 161–186.

Escuder-Viruete, J., Contreras, F., Stein, G., Urien, P., Joubert, M., Pérez-Estaún, A.,Friedman, R., Ullrich, T.D., 2007a. Magmatic relationships and ages betweenadakites, magnesian andesites and Nb-enriched basalt-andesites from Hispaniola:record of a major change in the Caribbean island arc magma sources. Lithos 99,151–177.

Escuder-Viruete, J., Contreras, F., Joubert, M., Urien, P., Stein, G., Weis, D., Pérez-Estaún, A.,2007b. Tectónica y geoquímica de la Formación Amina: registro del arco isla caribeñoprimitivo en la Cordillera Central, República Dominicana. Boletín Geológico y Minero118 (2), 221–242.

Escuder-Viruete, J., Pérez-Estaún, A., Contreras, F., Joubert, M., Weis, D., Ullrich, T.D.,Spadea, P., 2007c. Plumemantle source heterogeneity through time: insights from theDuarte Complex, Central Hispaniola. Journal of Geophysical Research 112, B04203.doi:10.1029/2006JB004323.

Escuder-Viruete, J., Joubert, M., Urien, P., Friedman, R., Weis, D., Ullrich, T., Pérez-Estaún,A., 2008. Caribbean island-arc rifting and back-arc basin development in the LateCretaceous: geochemical, isotopic and geochronological evidence from CentralHispaniola. Lithos 104, 378–404.

Ewart, A., Collerson, K.D., Regelous, M., Wendt, J.I., Niu, Y., 1998. Geochemical evolutionwithin the Tonga–Kermadec–Lau Arc–Back-arc system: the role of varying mantlewedge composition in space and time. Journal of Petrology 39, 331–368.

Gerya, T.V., Yuen, D.A., Maresch, W.V., 2004. Thermomechanical modelling of slabdetachment. Earth and Planetary Science Letters 226, 101–116.

Gradstein, F.M., Ogg, J.G., Smith, A.G., 2004. A geologic time scale 2004. CambridgeUniversity Press. 610 pp.

Gribble, R.F., Stern, R.J., Newman, S., Bloomer, S.H., O'Hearn, T., 1998. Chemical andisotopic composition of lavas from the northern Mariana Trough: implications formagmagenesis in back-arc basins. Journal of Petrology 39, 125–154.

Hastie, A.H., Kerr, A.C., Pearce, J.A., Mitchell, S.F., 2007. Classification of altered volcanicisland arc rocks using immobile trace elements: development of the Th–Codiscrimination diagram. Journal of Petrology 48, 2341–2357. doi:10.1093/petrology/egm062.

Hastie, A.R., Kerr, A.C., Mitchell, S.F., Millar, I.L., 2008. Geochemistry and petrogenesis ofCretaceous oceanic plateau lavas in eastern Jamaica. Lithos 101, 323–343.

Hauff, F., Hoernle, K.A., Van den Bogaard, P., Alvarado, G.E., Garbe-Schínberg, C.D., 2000.Age and geochemistry of basaltic complexes in western Costa Rica: contributionsto the geotectonic of Central America. Geochemistry, Geophysics, Geosystems 1[1999gc000020].

Hawkesworth,C.J., Gallager,K.,Hergt, J.M.,McDermott, F., 1993.Mantleandslabcontributionsin arc magmas. Annual Reviews of Earth and Planetary Science 21, 175–204.

Hawkins, J.W., 1995. The geology of the Lau Basin. In: Taylor, B. (Ed.), Backarc Basins:Tectonics and Magmatism. Plenum Press, New York, pp. 63–138.

Hochstaedter, A.G., Gill, J.B., Peters, R., Broughton, P., Holden, P., Taylor, B., 2001. Across-arc geochemical trends in the Izu-Bonin arc: contributions from the subductingslab. Geochemistry Geophysics Geosystems 2 Paper number 2000GC000105.

Janney, P.E., Castillo, P.R., 2001. Geochemistry of the oldest Atlantic oceanic crustsuggests mantle plume involvement in the early history of the central AtlanticOcean. Earth and Planetary Science Letters 192, 291–302.

Jolly, W.T., Lidiak, E.G., 2006. Role of crustal melting in petrogenesis of the CretaceousWater Island Formation (Virgin Islands, northeast Antilles Island Arc). GeologicaActa 4, 7–33.

Jolly, W.T., Lidiak, E.G., Dickin, A.K., Wu, T.W., 2001. Secular geochemistry of CentralPuerto Rican island arc lavas: constraints on mesozoic tectonism in the easternGreater Antilles. Journal of Petrology 42, 2197–2214.

Jolly, W.T., Lidiak, E.G., Dickin, A.P., 2006. Cretaceous to mid-Eocene pelagic sedimentbudget in Puerto Rico and theVirgen Islands (northeast Antilles IslandArc). GeologicaActa 4, 35–62.

Jolly, W.T., Schellekens, J.H., Dickin, A.P., 2007. High-Mg andesites and related lavasfrom southwestern Puerto Rico (Greater Antilles Island Arc): petrogenetic linkswith emplacement of the Caribbean mantle plume. Lithos 98, 1–26.

Kelemen, P.B., Yogodzinski, G.M., Scholl, D.W., 2003. Along-strike variation in lavas of theAleutian island arc: genesis of highMg# andesite and implications for the continentalcrust. In: Eiler J. (Ed.) Inside the subduction factory. American Geophysical UnionMonograph vol. 138, pp. 1–54.

Kerr, A.C., Tarney, J., Marriner, G.F., Nivia, A., Saunders, A.D., 1997. The Caribbean–Colombian Cretaceous igneous province: The internal anatomy of an oceanicplateau. In: Mahoney, J.J., Coffin, M.F. (Eds.), Large Igneous Provinces. AGUWashington DC, pp. 123–144.

Kerr, A.C., Iturralde-Vinent, M.A., Saunders, A.D., Babbs, T.L., Tarney, J., 1999. A newplate tectonic model of the Caribbean: implications from a geochemicalreconnaissance of Cuban Mesozoic volcanic rocks. Geological Society of AmericaBulletin 111, 1581–1599.

Kerr, A.C., Tarney, J., Kempton, P.D., Spadea, P., Nivia, A., Marriner, G.F., Duncan, R.A.,2002. Pervasive mantle plume head heterogeneity: evidence from the lateCretaceous Caribbean–Colombian oceanic plateau. Journal of Geophysical Research107 (B7). doi:10.1029/ 2001JB000790.

Kesler, S.E., Russell, N., Polanco, J., McCurdy, K., Cumming, G.J., 1990. Geology andgeochemistry of the Early Cretaceous Los Ranchos Formation, central DominicanRepublic. In:Mann, P.,Draper, G., Lewis, J.F. (Eds.), Geologic andTectonicDevelopmentof the North America–Caribbean Plate Boundary in Española: Geological Society ofAmerica Special Paper, vol. 262, pp. 187–201.

Kesler, S.E., Campbell, I.H., Allen, C.h.M., 2005. Age of the Los Ranchos Formation,Dominican Republic: timing and tectonic setting of primitive island arc volcanismin the Caribbean region. Geological Society of America Bulletin 117, 987–995.

Krebs, M., Maresch,W.V., Schertl, H.-P., Baumann, A., Draper, G., Idleman, B., Münker, C.,Trapp, E., 2007. The dynamics of intra-oceanic subduction zones: A directcomparison between fossil petrological evidence (Rio San Juan Complex, DominicanRepublic) and numerical simulation. Lithos 103, 106–137.

Lapierre, H., Dupui, V., Lepinay, B.M., Tardy, M., Ruiz, J., Maury, R.C., Hernandez, J.,Loubert, M., 1997. Is the Lower Duarte Complex (Hispañiola) a remnant of theCaribbean plume generated oceanic plateau? Journal of Geology 105, 111–120.

Lapierre, H., Dupuis, V., de Lepinay, B.M., Bosch, D., Monie, P., Tardy, M., Maury, R.C.,Hernandez, J., Polve, M., Yeghicheyan, D., Cotten, J., 1999. Late Jurassic oceanic crustand upper cretaceous Caribbean plateau picritic basalts exposed in the Duarteigneous complex, Hispaniola. Journal of Geology 107, 193–207.

Lapierre,H., Bosch,D., Dupuis, V., Polvé,M.,Maury, R.,Hernandez, J.,Monié, P., Yeghicheyan,D., Jaillard, E., Tardy,M., de Lepinay, B., Mamberti,M., Desmet, A., Keller, F., Senebier, F.,2000. Multiple plume events in the genesis of the peri-Caribbean Cretaceous oceanicplateau province. Journal of Geophysical Research 105, 8403–8421.

Lázaro, C., García-Casco, A., Rojas Agramonte, Y., Kröner, A., Neubauer, F., Iturralde-Vinent,M., 2008. Fifty-five-million-year history of oceanic subduction and exhumation at thenorthern edge of the Caribbean plate (Sierra del Convento mélange, Cuba). Journal ofMetamorphic Geology. doi:10.1111/j.1525-1314.2008.00800.

Leat, P.T., Pearce, J.A., Barker, P.F., Millar, I.L., Barry, T.L., Larter, R.D., 2004. Magmagenesis and mantle flow at a subducting slab edge: the South Sandwich arc-basinsystem. Earth and Planetary Science Letters 227, 17–35.

Lebrón, M.C., Perfit, M.R., 1994. Petrochemistry and tectonic significance of Cretaceousisland-arc-rocks, Cordillera Oriental, Dominican Republic. Tectonophysics 229,69–100.

Lewis, J.F., Astacio, V.A., Espaillat, J., Jiménez, J., 2000. The occurrence of volcanogenicmassive sulfide deposits in the Maimon Formation, Dominican Republic: the Cerrode Maimón, Loma Pesada and Loma Barbuito deposits. In: Sherlock, R., Barsch, R.,Logan, A. (Eds.), VMS deposits of Latin America. Geological Society of CanadaSpecial Publication. 223–249 pp.

Lewis, J.F., Escuder-Viruete, J., Hernaiz Huerta, P.P., Gutiérrez, G., Draper, G., 2002.Subdivisión Geoquímica del Arco Isla Circum-Caribeño, Cordillera Central Domini-cana: Implicaciones para la formación, acreción y crecimiento cortical en un ambienteintraoceánico. Acta Geológica Hispánica 37, 81–122.

Lewis, J.F., Draper, G., Proenza, J., Espaillat, J., Jiménez, J., 2006. Ophiolite-related ultramaficrocks (Serpentinites) in the Caribbean: a review of their occurrence, composition,origin, emplacement and Ni-laterite soil formation. Geológica Acta 4, 7–28.

Ludwig, K.R., 2003. Isoplot 3.00: a geochronological toolkit for Microsoft Excel. BerkeleyGeochronology Center Special Publication No. 4.

Mann, P., 1999. Caribbean sedimentary basins: classification and tectonic setting fromJurassic to Present. In: Mann, P. (Ed.), Caribbean Basins: Sedimentary Basins of theWord, vol. 4, pp. 3–31.

Marchesi, C., Garrido, C.J., Godard, M., Proenza, J.A., Gervilla, F., Blanco-Moreno, J., 2006.Petrogenesis of highly depleted peridotites and gabbroic rocks from the Mayarí-Baracoa ophiolitic belt (eastern Cuba). Contribution to Mineralogy and Petrology151, 717–736.

Marchesi, C., Garrido, C.J., Bosch, D., Proenza, J.A., Gervilla, F., Monié, P., Rodríguez-Vega,A., 2007. Geochemistry of Cretaceous magmatism in eastern Cuba: recycling ofNorth American continental sediments and implications for subduction polarity inthe Greater Antilles Paleo-arc. Journal of Petrology 48, 1813–1840.


Martinez, F., Taylor, B., 2002. Mantle wedge control on backarc crustal accretion. Nature416, 417–420.

Myczynski, R., Iturralde-Vinent, M., 2005. The Late Lower Albian Invertebrate Fauna ofthe Río Hatillo Formation of Pueblo Viejo, Dominican Republic. Caribbean Journal ofScience 41 (4), 782–796.

Peacock, S.M., Wang, K., 1999. Seismic consequence of warm versus cool subductionmetamorphism: examples fromsouthwest andnortheast Japan. Science 286, 937–939.

Pearce, J.A., Parkinson, I.J., 1993. Trace element models for mantle melting: applicationto volcanic arc petrogenesis. In: Pritchard, H.M., Alabaster, T., Harris, N.B.W., Nearly,C.R. (Eds.), Magmatic Processes and Plate Tectonics: Geological Society of LondonSpecial Publication, vol. 76, pp. 373–403.

Pearce, J.A., Peate, D.W., 1995. Tectonic implications of the composition of volcanic arcmagmas. Earth and Planetary Science Annual Review 23, 251–285.

Pearce, J.A., Baker, P.E., Harvey, P.K., Lui, W., 1995. Geochemical evidence for subductionfluxes, mantle melting and fractional crystallization beneath the South Sandwichisland arc. Journal of Petrology 36, 1073–1109.

PETDB, 2007. Petrological database of the ocean floor. http://petdb.ldeo.columbia.edu/petdb.

Pindell, J.L., Kennan, L., Maresch, W.V., Stanek, K.P., Draper, G., Higgs, R., 2005. Plate-kinematics and crustal dynamics of circum-Caribbean arc–continent interactions:tectonic controls on basin development in Proto-Caribbean margins. In: Lallemant,A., Sisson, V.B. (Eds.), Caribbean–South American Plate Interactions: GeologicalSociety of America Special Paper, vol. 394, pp. 7–52.

Plank, T., Langmuir, C.H., 1993. Tracing trace elements from sediment input to volcanicoutput at subduction zones. Nature 362, 739–742.

Proenza, J.A., Díaz-Martínez, R., Iriondo, A., Marchesi, C., Melgarejo, J.C., Gervilla, F., Garrido,C.J., Rodríguez-Vega, A., Lozano-Santacruz, R., Blanco-Moreno, J.A., 2006. PrimitiveCretaceous island-arc volcanic rocks ineasternCuba: theTénemeFormation. GeologicaActa 4, 103–121.

Rankin, D.W., 1631. 2002. Geology of St. John, U. S., Virgin Islands. U.S. Geological.Survey. Professional Paper, pp. 1–36.

Révillon, S., Hallot, E., Arndt, N., Chauvel, C., Duncan, R.A., 2000. A complex history forthe Caribbean plateau: petrology, geochemistry, and geochronology of the BeataRidge, South Hispaniola. Journal of Geology 108, 641–661.

Schmidt, M.W., Poli, S., 1998. Experimentally based water budgets for dehydrating slabsand consequences for arc magma generation. Earth and Planetary Science Letters163, 361–379.

Singer, B. S., B. R. Jicha, W. P. Leeman, N. W. Rogers, M. F. Thirlwall, J. Ryan, Nicolaysen,K.E., 2007. Along-strike trace element and isotopic variation in Aleutian Island arcbasalt: Subduction melts sediments and dehydrates serpentine. Journal ofGeophysical Research 112, B06206. doi:10.1029/2006JB004897.

Sinton, C.W., Duncan, R.A., Storey, M., Lewis, J., Estrada, J.J., 1998. An oceanic flood basaltprovince within the Caribbean plate. Earth Planetary Science Letters 155, 221–235.

Stalder, R., Foley, S.F., Brey, G.P., Horn, I., 1998. Mineral-aqueous fluid partitioning oftrace elements at 900–1200 °C and 3.0–5.7 GPa: new experimental data for garnet,

clinopyroxene and rutile and implications for mantle metasomatism. GeochimicaCosmochima Acta 62, 1781–1801.

Stern, R.J., 2002. Subduction zones. Reviews of Geophysics 40, 1012. doi:10.1029/2001RG000108.

Stolper, E.M., Newman, S., 1994. The role of water in the petrogenesis of MarianaTrough magmas. Earth and Planetary Science Letters 121, 293–325.

Su, Y., Langmuir, C.H., 2003. Global MORB chemistry compilation at the segment scale,PhD Thesis, Department of Earth and Environmental Sciences, Columbia University.http://petdb.ldeo.columbia.edu/documentation/morbcompilation/.

Sun, S.S., McDonough, W.F., 1989. Chemical and isotopic systematics of oceanic basalts:implications for mantle compositions and processes. In: Saunders, A.D., Norry, M.J.(Eds.),Magmatismin theOceanBasins:Geological Societyof LondonSpecial Publication,vol. 42, pp. 313–345.

Swinden, H.S., Jenner, G.A., Szybinski, Z.A., 1997. Magmatic and tectonic evolution of theCambrian–Ordovician Laurentian margin of Iapetus: geochemical and isotopicconstraints from the Notre Dame subzone, Newfoundland. In: Sinha, A.K., Whalen,J.B., Hogan, J.P. (Eds.), The Nature of Magmatism in the Appalachian Orogen, 191,pp. 337–365.

Tatsumi, Y., Hanyu, T., 2003. Geochemical modeling of dehydration and partial melting ofsubducting lithosphere: toward a comprehensive understanding of high-Mg andesiteformation in theSetouchivolcanicbelt, SWJapan.GeochemistryGeophysicsGeosystems4 [1081GC000080].

Taylor, B., Martinez, F., 2003. Back-arc basin systematics. Earth and Planetary ScienceLetters 210, 481–497.

Thompson, P.M.E., Kempton, P.D., White, R.V., Saunders, A.D., Kerr, A.C., Tarney, J.,Pringle, M.S., 2004. Elemental, Hf–Nd isotopic and geochronological constraints onan island arc sequence associated with the Cretaceous Caribbean Plateau: Bonaire,Dutch Antilles. Lithos 74, 91–116.

Weis D., Kieffer B., Maerschalk C., Pretorius W., and Barling J. (2005), Highprecision Pb-Sr-Nd-Hf isotopic characterization of USGS BHVO-1 and BHVO-2 referencematerials. Geochem. Geophys. Geosyst. 6, Q02002. doi:10.1029/2004GC000852.

Weis, D., Kieffer, B., Maerschalk, C., Barling, J., de Jong, J., Willians, G.A., Hanano, D.,Pretorius, W., Scoates, J.S., Goolaerts, A., Friedman, R.M., Mahoney, J.B., 2006. High-precision isotopic characterization of USGS reference materials by TIMS and MC-ICP-MS. Geochemistry Geophysics Geosystems 7 [2006GC001283].

Winchester, J.A., Floyd, P.A., 1977.Geochemicaldiscriminationofdifferentmagmaseries andtheirdifferentiationproducts using immobile elements. Chemical Geology 20, 325–343.

Woodhead, J.D., Eggins, S.M., Johnson, R.W., 1998. Magma genesis in the New Britainisland arc: further insights into melting and mass transfer processes. Journal ofPetrology 39, 1641–1668.

Yogodzinski, G.M., Lees, J.M., Churikova, T.G., Dorendorf, F., Woerner, G., Volynets, O.N.,2001. Geochemical evidence for the melting of subducting oceanic lithosphere atplate edges. Nature 409, 500–504.

http://petdb.ldeo.columbia.edu/petdbhttp://petdb.ldeo.columbia.edu/petdbhttp://petdb.ldeo.columbia.edu/documentation/morbcompilation/

Geochemical characteristics of the Río Verde Complex, Central Hispaniola: Implications for the .....IntroductionGeodynamic settingThe Caribbean island-arcThe geology of Central Hispaniola

Geology of the Río Verde ComplexGeochronologyU–Pb samples40Ar/39Ar samplesInterpretation

GeochemistryAnalytical methodsChemical changes due to alteration and metamorphismGeochemical characteristics of the Río Verde Complex rocks and comparisonsDiscussionTrace element ratio variations and implicationsSr–Nd isotope variations and implications

Petrogenesis and comparisonsModeling of mantle melting and magma sourcesIntroductionSource characterizationIsotope-trace element results

Tectonic implications

ConclusionsAcknowledgementsSupplementary dataReferences

geochemical characteristics of the río verde complex ...pcigr.eos.ubc.ca › publications ›...

Documents