Mineralogy, Geochemistry and Geochronology of Granitoid Plutons of Dudhi Gneissic Complex, Mahakoshal Belt, Central India

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1 Mineralogy, Geochemistry and Geochronology of Granitoid Plutons of Dudhi Gneissic Complex, Mahakoshal Belt, Central India Thesis submitted to Kumaun University ar for the requirement of degree of Es t el Doctor of Philosophy in Geology Sita Bora Department of Geology Centre of Advanced Study Kumaun University Nainital July, 2014

2 Dedicated to Parents and Supervisor

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5 Acknowledgments I highly appreciate and grateful, throughout my life, to Dr. R. A. Singh (my teacher) who has introduced and taught Geology during graduation in the year and I consider him founder of the subject Geology to me. I admire him for his valuable advice and career counselling. I extend my sincerest gratitude to all my teachers who gave me strength to make challenging career in the study of rocks during my post-graduation in the year Special and sincerest thanks to Prof. C. C. Pant for his excellent teaching on fundamental aspects and principle of Sedimentology that helped me a lot while understanding and documentation of sedimentary lithounits associated with magmatic bodies in my research area. I always admire and thankful to my teachers Professors A. K. Sharma, G. K. Sharma, R. Upadhyay, P. K. Goswami, B. S. Kotliya and Late S. N. Lal, who taught me all sphere of geology during post-graduation and for their continuous encouragement during the course of present research work. I extend my regards and sincerest thanks to Prof. Anand K. Srivastava who cared and acted as mentor at initial period of my research wok and because of his valuable guidance I was able to trace and reached in the search of magmatic bodies in and around the Renukoot locality of Sonbhadra district of U.P. I am highly indebted to Prof. Santosh Kumar who has not only supervise me but also acted as a founder of Igneous Petrology for me who had introduced and taught us I of igneous petrology which enhanced, replenished, recharged us continuously with knowledge of magmas during the course of research work, and hope we shall always be at receiving end in near future too. Without his inspiration, guidance, motivation and more than that his patient, who is immeasurable, I would have not been able to complete the task in proper way and well in time. I greatly appreciate him for providing me several time opportunities wherever I lost my sincerity. I also express hearty thanks to Dr. Subhra Roy who is truly behind the success of all of us. Because of her real effort, kindness and family-like support, I am able to complete positively the present research work.

6 The journey of the present research work was not so easy, but it became smooth because of moral support rendered by Dr. Rajesh Sharma and Dr. D. R. Rao, who constantly helped and encouraged me while conducting analytical works at Wadia Institute of Himalayan Geology, Dehradun. Dr. Rao has not only helped and guided me during EPMA but also taught about the instrument. I am also thankful to Dr. S. S. Thakur who helped me during EPMA work. I am thankful to Dr. N. K. Saini, Dr. P. P. Khanna for extending analytical helps on XRF and ICP-MS. I am equally thankful to their supporting technical staffmembers Shekhar ji, Rawat ji, Bahuguna ji, Girish ji, Chand Singh ji, D. P. Saklani ji and Mr. Thapliyal ji and many others who directly and indirectly helped me in my research work while my stay at Wadia Institute of Himalayan Geology, Dehradun. I am always thankful to Dr. Umesh K. Sharma, Scientist D, Department of Science and Technology, New Delhi, who encouraged and supported me in every aspect of my research work and continuously motivated me for making career in the field of research. I highly acknowledge the DST-funded project work on CITZ (SR/S4/ES- 402/2009) in which I worked as JRF and SRF and also to Prof. Talat Ahmed (PI of the project) and also to Prof. A. K. Chaudhury, Prof. Sandeep Singh and Prof. R. C. Patel for extending lab facilities for mineral separation at Indian Institute of Technology, Roorkee and Department of Geophysics at Kurukshetra University, Kurukshetra. I deeply acknowledge the DST, New Delhi for International travel support imparting training on SHRIMP at KBSI, Korea. I am highly thankful to Dr. Keewook Yi and Dr. Namhoon Kim at SHRIMP Centre, Korea Basic Science Institute, Korea, who facilitated and introduced me with the advanced technique of Zircon Chronology. They taught and helped me in processing zircon samples and data analysis. They also took care while I was working at SHRIMP centre. Naveen Chauhan and Mukesh, Scientists at KBSI, Korea helped me a lot during my stay at Korea. Tae Ho Lee, Suk_Zu, Shein_a, He_Je, Jeong, Chehang_Park (research students) helped me while analyzing the zircon sample at KBSI, Korea. I am grateful to Dr. V. Balram who provided opportunities to learn geochronology and GCDkit programme that helped me understanding elemental

7 chemistry, modelling and isotope geochemistry. I am thankful to course mentors particularly Prof. Randall R. Parrish, Dr. V. Janousek and Prof. J-F Moyen for imparting training at NGRI, Hyderabad. I am thankful to Dr. S. Raju, Dy Director General, GSI, Chennai for the help procuring geological information on the study area. I also express my deep sense of gratitude to Dr. Brajesh Singh who helped and guided me throughout the research work. I extend my sincere thanks to Manjari Pathak and Ritu Chauhan for their support, help, motivation, and for sparing precious time during the first phase of field investigation. I am very much thankful to Meraj and Naushad for extending help while sampling during third phase of field work in and around Sidhi area, Madhya Pradesh. I also extend my hearty thanks to my all friends especially to Kowete-ü Sekhamo, Samom Jwellys and Mayank Joshi for their concern and support while processing samples at IIT-Roorkee, WIHG and for providing literature. I am thankful to my friends Thomas and Thsope Medo for helping me during analytical works at WIHG, Dehradun. I am thankful to all research scholars at WIHG, Dehradun especially to Sovik and Kaushik for helping me while preparing and polishing the EPMA slides. I extend my sincerest thanks to Maibam Rogibala Di and Ningthoujam Surdas Singh for their support, guidance and care during my stay at Indian Institute of Technology, Roorkee. I am highly thankful to Pramjeet Singh for helping and guiding me during the course of zircon separation at Geophysics Department, Kurukshetra University. I extend my sincere thanks to all the staff member of Department of Geology, Centre of Advanced Study, Kumaun University specially to Ms. R. C. Upadhaya for making excellent thin sections; Bachhi Singh Dhaila for chipping and processing my rock samples; K. D. Mathela, Chandan Singh Dhaila, Harish, Vinod Joshi, Ganga Datt, V. N. Ghoshal, Bhuwan Joshi, Sarvesh ji and Khem Singh for helping me in official works during the entire course of research work. I am highly thankful to Mr. Manohar Singh Rawat, who helped me while compilation of the present work. I express my thanks to all research students of the geology department, particularly to Lalit, Vivekanand, Anoop, Sanjit Kundu, Chitra, Akhre, Harshita, Hansa, Gajendra, Vivek, Saurabh, Laxman and

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9 Contents Chapter I: Introduction The planet Earth Granite Volcanic-plutonic connexion Granite magmatism in relation to plate tectonics Review of status of knowledge on study area Objectives of present study Chapter II: Geology and Field Relations Introduction Regional geology and tectonics Supracrustal belts Granulite belts Geology of Mahakoshal belt Field observation Harnakachar granitoid (HG) pluton Jhirgadandi granitoid (JG) pluton Asnadhor locality Saliadih locality Jhirgadandi locality Pipraha locality Katoli granitoid (KG) pluton Dudhi granite gneiss Sidhi granitic gneiss Raspahari granitoid (RG) pluton Nerueadamar (NG) and Tumiya (TG) granitoids Volcanics of Mahakoshal Belt Magnetic susceptibility of granitoids and volcanic lithounits... 40

10 Chapter III: Methodology and Instrumentation Techniques Introduction Field Technique Method of sample preparation Microscopic method Magnetic susceptibility Analytical techniques Loss on ignition (LOI) X-ray fluorescence (XRF) spectrometry Inductively coupled plasma mass spectrometry (ICP-MS) U-Th-Pb SHRIMP zircon chronology Analysis of data and used software Chapter IV: Petrography and Mineralogy Introduction Petrography Harnakachar granitoid (HG) pluton Jhirgadanadi granitoid (JG) pluton Katoli granitoid (KG) pluton Dudhi granite gneiss (DG) Raspahari granitoid pluton Nerueadamar (NG) and (TG) Tumiya granitoid plutons Volcanic lithounits Mineral Chemistry Pyroxene Amphibole Classification of amphibole Al-in-amphibole geobarometer Amphibole-plagioclase geothermometer Feldspar Classification of feldspar Feldspar geothermometers

11 Two-feldspar thermometry Single feldspar thermometry Mica Group Biotite chemistry Composition and classification Nature of host granitoid magmas Muscovite chemistry Garnet Chapter V: Geochemistry Introduction Nomenclature Harnakachar granitoid (HG) pluton Jhirgadandi granitoid (JG) pluton Katoli granitoid (KG) pluton Raspahari granitoid (RG) pluton Tumiya (TG) and Nerueadamar (NG) granitoid plutons Volcanic lithounits Major oxide and CIPW norm Harnakachar granitoid (HG) pluton Jhirgadandi granitoid (JG) pluton Katoli granitoid (KG) pluton Dudhi granite gneiss (DG) Raspahari granitoid (RG) pluton Nerueadamar (NG) and Tumiya (TG) granitoid plutons Volcanic lithounits Harker geochemical variation Normalized trace including rare earth elements Harnakachar granitoid (HG) pluton Jhirgadandi granitoid (JG) pluton

12 5.5.3 Katoli granitoid (KG) pluton Dudhi granite gneiss (DG) Raspahari granitoid (RG) pluton Tumiya (TG) and Nerueadamar (NG) granitoid plutons Volcanic lithounits Chapter VI: U-Pb Zircon Chronology Introduction NG pluton: Product of collisional-related thermal event (~1880 Ma) Tumiya pluton: Product of late collisional-related thermal event (~1780 Ma) Vast coeval mafic-felsic magmatism: Major thermal events (~1750 Ma) Jhirgadandi granitoid (JG) Peraluminous microgranular enclave (JE) Metaluminous microgranular enclave (JE) Dudhi granite gneiss (DG) Porphyritic volcanic Coeval mafic-felsic magmatism: minor thermal event (~1730Ma) Katoli granitoid Microgranular enclave (K17E) in KG Age of provenance from quartzite of Harnakachar: evolution of an intra- magmatic or plutonic basin Magmatic event ( ~1710 Ma): HG pluton with older xenolith Chapter VII: Petrogenetic and Geodynamic Discussion Introduction Field evidences Basement of Mahakoshal Belt

13 7.2.2 Evidences of magma intrusion, assimilation, mingling, mixing and undercooling of mafic to hybrid magma globules Magnetite to ilmenite series of granitoids Tectonic scenario and questions remained unanswered Pre to syn sedimentation of magmatism in Mahakoshal Belt Petrographic features of genetic value Crystallization of HG magma and its interaction with enclaves Evidence of JE mingling and syn-crystallization in JG Crystallization of KG magma and its interaction with enclaves Migmatized nature of DG granite gneiss Magmatic processes and protolith assessment of RG pluton Magmatic processes and protolith assessment of NG and TG melts Textural similarities among the granitoid plutons Volcanism and assimilation with country rocks Porphyritic rhyolitic xenoliths in mafic volcanics of Sidhi area: Evidence of fragments of Bundelkhand craton basement Mineral chemical evolution of magmas Nature of JG melt: evidence from pyroxene composition Redox-state of evolving melts under variable P-T conditions: imprinted on amphibole composition Subsolvus granites: evidence from feldspar thermometry Redox conditions of granitoid magmas: evidence from biotite chemistry Water fugacity (ƒh2o) of granitoid melts Tectonic implications: based on biotite chemistry Muscovite composition as an indicator of

14 barren and mineralized granites Geochemical Petrology Granite typology and protolith assessment Depth of granitoid magma emplacement based on normative composition Recognition of magmatic processes Geochemical evolution of HG and HE Mantle derived HG melt fractionation without assimilation Geochemical evolution of JG pluton Mixing between fractionating mafic and felsic magmas Chemically modified JE REE features of mafic and felsic magma fractionation Geochemical evolution of KG pluton Elemental exchange during mingling of mafic-felsic magmas Fractional crystallization (FC): evidence from REE chemistry Geochemical evolution of DG pluton Geochemical evolution of RG pluton Evidence of trace and REE partial equilibration Geochemical evolution of NG and TG plutons Protolith for generation of leucocratic NG and TG melts Low-to-high degree of partial melting Comparison of lithounits with

15 lower, upper and bulk continental crusts Tectonic setting of plutonic and volcanic lithounits Syn-to-post collisional felsic plutonism Fractional crystallization assimilation (AFC) in post-collisional volcanics U-Pb SHRIMP zircon chronology: inferred sequence of geological events Opening of the Mahakoshal Basin: evidence from inherited and magmatic zircons of NG and TG plutons Slow rate of Mahakoshal Basin closure: evidence from collisional-related plutonism Bimodal mafic-felsic magmatism in post-collision tectonic setting Coeval mafic-felsic magma interaction in plutonic setting Intra-plutonic sedimentation A viable model for the evolution of Mahakoshal Belt Comparison of past Mahakoshal orogeny with present younger Himalayan orogeny in Indian subcontinent Chapter VIII: Summary and Conclusions References