Geochemical Systematics of the Mauranipur-Babina Greenstone Belt
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Geoscience Frontiers 9 (2018) 769e788 HOSTED BY Contents lists available at ScienceDirect China University of Geosciences (Beijing) Geoscience Frontiers journal homepage: www.elsevier.com/locate/gsf Research Paper Geochemical systematics of the Mauranipur-Babina greenstone belt, Bundelkhand Craton, Central India: Insights on Neoarchean mantle plume-arc accretion and crustal evolution S.P. Singh a, K.S.V. Subramanyam b, C. Manikyamba b,*, M. Santosh c,d, M. Rajanikanta Singh b, B. Chandan Kumar e a Department of Geology, Institute of Earth Sciences, Bundelkhand University, Jhansi, U.P, 284128, India b CSIR-National Geophysical Research Institute, Uppal Road, Hyderabad, 500007, India c Department of Earth Sciences, University of Adelaide, Australia d School of Earth Science & Resources, China University of Geosciences, Beijing, China e Department of Geology, Central University of Kerala, Kasaragod, Kerala, 671316, India article info abstract Article history: The Neoarchean Bundelkhand greenstone sequences at Mauranipur and Babina areas within the Received 1 February 2017 Bundelkhand Gneissic Complex preserve a variety of magmatic rocks such as komatiitic basalts, basalts, Received in revised form felsic volcanic rocks and high-Mg andesites belonging to the Baragaon, Raspahari and Koti Formations. 8 August 2017 The intrusive and extrusive komatiitic basalts are characterized by low SiO (39e53 wt.%), high MgO Accepted 29 August 2017 2 (18e25 wt.%), moderately high Fe O (7.1e11.6 wt.%), Al O (4.5e12.0 wt.%), and TiO (0.4e1.23 wt.%) Available online 16 October 2017 2 3 2 3 2 with super to subchondritic (Gd/Yb)N ratios indicating garnet control on the melts. The intrusive komatiitic suite of Ti-enriched and Al-depleted type possesses predominant negative Eu and positive Keywords: fi Bundelkhand craton Nb, Ti and Y anomalies. The chemical composition of basalts classi es them into three types with varying Greenstone belts SiO2,TiO2, MgO, Fe2O3,Al2O3 and CaO. At similar SiO2 content of type I and III basalts, the type II basalts fi Mantle dynamics show slightly high Al2O3 and Fe2O3 contents. SigniP cant negative anomalies of Nb, Zr, Hf and Ti, slightly Plume-arc accretion enriched LREE with relatively flat HREE and low REE contents are observed in type I and II basalts. Type Neoarchean crustal evolution III basalts show high Zr/Nb ratios (9.8e10.4), TiO2 (1.97e2.04 wt.%), but possess strikingly flat Zr, Hf, Y and Yb and are uncontaminated. Andesites from Agar and Koti have high SiO2 (55e64 wt.%), moderate TiO2 (0.4e0.7 wt.%), slightly low Al2O3 (7e11.9 wt.%), medium to high MgO (3e8 wt.%) and CaO contents (10e17 wt.%). Anomalously high Cr, Co and Ni contents are observed in the Koti rhyolites. Tholeiitic to calc alkaline affinity of mafic-felsic volcanic rocks and basalteandesiteedaciteerhyolite differentiation indicate a mature arc and thickened crust during the advanced stage of the evolution of Neoarchean Bundelkhand greenstone belt in a convergent tectonic setting where the melts were derived from partial melting of thick basaltic crust metamorphosed to amphibolite-eclogite facies. The trace element systematics suggest the presence of arc-back arc association with varying magnitudes of crust-mantle interaction. La/Sm, La/Ta, Nb/Th, high MgO contents (>20 wt.%), CaO/Al2O3 and (Gd/Yb)N > 1 along with the positive Nb anomalies of the komatiite basalts reflect a mantle plume source for their origin contaminated by subduction- metasomatized mantle lithosphere. The overall geochemical signatures of the ultramafic-mafic and felsic volcanic rocks endorse the Neoarchean plume-arc accretion tectonics in the Bundelkhand greenstone belt. Ó 2018, China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/). 1. Introduction Archean greenstone belts present in different cratons * Corresponding author. Geochemistry Division, CSIR-National Geophysical comprising wide variety of volcano-sedimentary rocks recording Research Institute, Uppal Road, Hyderabad, Telangana, 500007, India. E-mail address: [email protected] (C. Manikyamba). various tectonic imprints and evolutionary history, intrusive and Peer-review under responsibility of China University of Geosciences (Beijing). extrusive magmatic episodes, metamorphism, metasomatism and https://doi.org/10.1016/j.gsf.2017.08.008 1674-9871/Ó 2018, China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC- ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). 770 S.P. Singh et al. / Geoscience Frontiers 9 (2018) 769e788 mineralization (Weaver and Tarney, 1981; Pearce, 2014). Based on by the MesoeNeoproterozoic sedimentary rocks of Vindhyan Su- geological, geophysical, geochemical and geochronological in- pergroup (Ray, 2006) and in the south-east and south by Paleo- vestigations, several studies have suggested that Phanerozoic proterozoic Bijawar Group (Pandey et al., 2011) comprising low type plate tectonics were operative in the Archean era and grade volcano-sedimentary rocks. The south-western fringe is correlated these with the modern-style convergent margin pro- demarcated by a small outcrop of the Deccan basalt and the cesses (Condie, 2000; Benn et al., 2006; Furnes et al., 2014; northern part is hidden under the recent alluvium of Indo-Gangetic Santosh et al., 2016; Yang et al., 2016; Yang and Santosh, 2017). Plains (Singh et al., 2007). The Bundelkhand massif is mainly A peak in continental crustal growth at 2.7 Ga, existence of composed of (1) Mesoarchean Bundelkhand Gneissic Complex hotter Archean mantle, eruption of komatiites, occurrence of (BnGC) with tonaliteetrondhjemiteegranodiorites (TTG); (2) Neo- tonaliteetrondhjemiteegranodiorite (TTG) and adakites that are archean greenstone sequences consisting a variety of volcano- geochemically analogous to their Phanerozoic counterparts lend sedimentary rocks; (3) subsequent granites intruded into the support to the operation of plate tectonics during Archean greenstone belt sequences marks a major geological event for the including both mantle plume and island arc processes (Isley and cratonization and (4) Proterozoic quartz reefs and mafic dykes Abbott, 1999; Kerrich and Polat, 2006; Polat and Kerrich, 2006 emplaced subsequent to transformation into a stable craton that and references there in). Convergent margins act as magma pro- are related to crustal scale extension and shearing (Basu, 1986; Rao ducing centres through partial melting in the mantle wedge and et al., 2005; Pati et al., 2007; Singh, 2012; Bhattacharya and Singh, subducted oceanic slab representing important sites of crustal 2013). growth in both Precambrian and Phanerozoic Eras (Taylor and The Neoarchean Bundelkhand granitoids occur extensively over McLennan, 1985; Rudnick, 1995; Tatsumi, 2005; Stern and a large part of the Bundelkhand Craton (>70% of the area), intrude Johnson, 2010; Xiao and Santosh, 2014; Santosh et al., 2015, the greenstone sequences and high grade (amphibolite-granulite 2017). Intraoceanic arc lithologies such as boninites, low-Ti tho- facies) metamorphic (Singh et al., 2007). The Neoarchean felsic leiites, picrites, high magnesian andesites, and Nb-enriched ba- magmatism (2532e2516 Ma; Mondal et al., 2002; Kumar et al., salts from greenstone belts of different Archean cratons and their 2010; Saha et al., 2011; Joshi et al., 2013; Singh and Slabunov, Phanerozoic counterparts provide clue to understand convergent 2015) is considered to mark the final stabilization of the craton margin tectonics and crustal growth (Manikyamba et al., 2004, (Ray et al., 2015). This belt is about 120 km long and 6e7 km wide, 2005, 2009, 2012, 2015a,b; Manikyamba and Khanna, 2007; and carries EeW trending disseminated linear bodies in the central Manikyamba and Kerrich, 2012; Baitsch-Ghirardello et al., 2014). part of the craton (Mohan et al., 2012; Singh, 2012; Ray et al., 2015; The lithological assemblages of the Neoarchean greenstone belts Singh and Slabunov, 2015; Fig. 1B). The EeW trending greenstone from different cratons of the world preserve distinct geological belt has extensive outcrops at Umari-Bhauti (near Mohar), Babina- and geochemical signatures of subduction processes (Hollings and Dhaura (Fig. 1C) and Baragaon-Mauranipur (Fig. 1D) areas and is Kerrich, 2000; Smithies et al., 2005; Polat and Kerrich, 2006; Zhai dismembered by younger granites and quartz reefs. The greenstone and Santosh, 2011; Shchipansky et al., 2012; De Joux et al., 2014; belt is easily distinguished from rocks of BnGC by their grade of Furnes et al., 2014; Santosh et al., 2016). metamorphism, lithological associations, texture, structures and The Bundelkhand Craton is one of the prominent Archean nuclei presence of sheared angular relationship with Bundelkhand in the northern part of the Indian shield across the north of gneisses (Singh et al., 2007). The metamorphic P-T conditions as SoneNarmada lineament (Fig. 1). Paleoarchean TTGs, Mesoarchean derived from the garnet-sillimanite Æ biotite Æ cordierite-feldspar- gneisses of 3551e3270 Ma (Mondal et al., 1998, 2002; Kaur et al., quartz and garnet-biotite-amphibole-plagioclase-quartz assem- 2014) and Neoarchean granitoids of 2583e2516 Ma (Mondal blages of gneisses (BnGC), range from 4.9 to 6.4 kbar and 680 to et al., 2002; Kumar et al., 2010; Pandey et al., 2011; Joshi et al., 730 C(Singh