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Evolution of a Granite Gneiss-Migmatite Terrane in Rajasthan: Melt Generation and Origin of Anjana Granite

  • D. B. GuhaEmail author
  • Sandip Neogi
  • Ausaf Raza
Chapter
Part of the Society of Earth Scientists Series book series (SESS)

Abstract

The granite gneiss and migmatitic terrane of southcentral Rajasthan around Devgarh-Madariya-Anjana areas in Rajsamand district has been geologically mapped and is found to contain rocks of individual precursor (protolith) identity. The major proportion of the precursor lithology (protolith) of the granite gneiss and migmatite terrane is mafic-ultramafic and pelitic rocks which were involved in regeneration through partial melting and formation of anatectic melt and its homogenisation and differentiation to produce magma of granitic composition. The other components of the migmatite terrane being chemogenic and arenaceous components, they did not participate in the regeneration through partial melting because of their inherent mineral composition not amenable to melting. The sequence of partial melt formation within the mafic-ultramafic-pelitic lithologies has been established through field evidences aided by chemico-mineralogical changes in the migmatite to the plutonic body of Anjana Granite. Chemically, it is seen that the Anjana Granite pluton is calkalkaline. It also indicates that during replacement from precursor mafic-ultramafic rocks, K2O and Al2O3 were released through melting in initial stages, which was also substantiated by lesser FeOt and higher normative orthoclase and corundum in the migmatites. EPMA studies of K-feldspar, plagioclase, biotite, and hornblende of Anjana Granite, migmatite and mafic enclaves show variable tetrahedral Al in biotites of the Anjana Granite in respect to the migmatite and mafic enclaves within the granite indicating biotite formed at varying higher temperatures to accommodate more tetrahedral sites with Al. The pargasitic hornblende is derived from common hornblende by addition of Na in A site and substitution of Al for Si. The EPMA data show Anjana Granite phase-I is Ab-An rich in which some of the plagioclase is replaced by Or as perthite growth whereas Anjana Granite phase-II is Or rich where Ab-An replaces Or during two feldspar growth or perthite–myrmekite formation. The dehydration melting reactions of pelitic and mafic precursor rocks produced partial melts of appropriate composition in a decompressive terrane. The melt, thus generated at depth, gathered into major granitic melt portions through folding and shear generated pathways and nucleation growth through shear instabilities; homogenised into granitic magma, and the magma intruded along the major shears within the terrane in forceful ballooning process making a ‘megaboudin’ like structure of the Anjana Granite pluton.

Keywords

Granite-Gneiss Migmatite Anjana Granite Greenstones Partial melt 

Notes

Acknowledgements

The authors acknowledge Sri A. Thiruvengadam, Addl. Director General and HoD of GSI, Western Region for permission to publish this paper. Chemical analysis from WR GSI and EPMA of mineral phases from GSI Bangalore are thankfully acknowledged.

References

  1. Bhattacharya, A. K., & Guha, D. B. (1988). Report on the study of high grade sequence and the associated rocks of the Sandmata Complex in parts of Udaipur district, Rajasthan. Progress report for FS 1987–88 GSI (Unpublished), 24p.Google Scholar
  2. Bhowmik, S. K., & Dasgupta, S. (2012). Tectonothermal evolution of the Banded Gneissic Complex in central Rajasthan, NW India: Present status and correlation. Journal of Asian Earth Sciences, 49, 339–348.CrossRefGoogle Scholar
  3. Buick, I. S., Allen, C., Pandit, M., Rubatto, D., & Hermann, J. (2006). The Proterozoic magmatic and metamorphic history of the Banded Gneissic Complex, central Rajasthan, India: LA-ICPMSU-Pb zircon constraints. Precambrian Research, 151, 119–142.CrossRefGoogle Scholar
  4. Cox, K. G., Bell, J. D., & Pankhurst, R. J. (1979). The interpretation of igneous rocks. London: George Allen and Unwin.CrossRefGoogle Scholar
  5. Dasgupta, S., Guha, D., Sengupta, P., Miura, H., & Ehl, J. (1997). Pressure-temperature fluid evolutionary history of the polymetamorphic Sandmata granulite complex, Northwestern India. Precambrian Research, 83, 267–290.CrossRefGoogle Scholar
  6. Dharma Rao, C. V., Santosh, M., Purohit, Ritesh, Wang, Junpeng, Jiang, Xingfu, & Kusky, Timothy. (2011). LA-ICP-MS U-Pb zircon age constraints on the Paleoproterozoic and Neoarchean history of the Sandmata Complex in Rajasthan within the NW Indian Plate. Journal of Asian Earth Sciences, 42(3), 286–305.CrossRefGoogle Scholar
  7. Ferry, J. M., & Spear, F. S. (1978). Experimental calibration of the partitioning of Fe and Mg between biotite and garnet. Contributions to Mineralogy and Petrology, 66, 113–117.CrossRefGoogle Scholar
  8. Guha, D. B. (1998). High-grade granulites of Sandmata-P-T conditions and metamorphic evolution. Bulletin Indian Geologists Association (P.U.,Chandigarh), 31(1.2), 75–81.Google Scholar
  9. Guha, D. B., & Bhattacharya, A. K. (1995). Metamorphic evolution and high-grade reworking of the Sandmata Complex granulites. Memoirs Geological Society of India, 31, 163–198.Google Scholar
  10. Gopalan, K., Mc Dougall, J. D., Roy, A. B., & Murali, A. V. (1990). Sm-Nd evidence of 3.3 Ga old rocks in Rajasthan, northwestern India. Precambrian Research, 48, 287–297.CrossRefGoogle Scholar
  11. Gupta, S. N., Arora, Y. K., Mathur, R. K., Iqballuddin, Prasad, B., Sahai, T. N., et al. (1997). The precambrian geology of the Aravalli Region, Southern Rajasthan and Northeastern Gujarat. Mem. Geol. Surv. India, v.123, pp. 262.Google Scholar
  12. Heron, A. M. (1953). The geology of central Rajputana. Memoir Geological Survey of India, 79, 389p.Google Scholar
  13. Holdaway, M. J., & Lee, S. M. (1977). Fe-Mg cordierite stability in high grade rocks based on experimental, theoretical and natural observations. Contributions to Mineralogy and Petrology, 63, 175–198.CrossRefGoogle Scholar
  14. Irvine, T. N., & Baragar, W. R. A. (1971). A guide to the chemical classification of the common volcanic rocks. Canadian Journal of Earth Sciences, 8, 523–548.CrossRefGoogle Scholar
  15. Mohanty, M., & Guha, D. B. (1995). Lithotectonic stratigraphy of dismembered greenstone sequence of the Mangalwar complex around Lawa Sardargarh and Parasali areas, Rajsamand district, Rajasthan. Memoir Geological Society of India, 31, 141–162.Google Scholar
  16. Perchuk, L. L., & Lavrenteva, I. V. (1983). Experimental investigation of exchange equilibria in the system cordierite–garnet–biotite. In S. K. Saxena (Ed.), Kinetics and equilibrium in mineral reactionsAdvances in physical geochemistry (Vol. 3, pp. 199–239). New York: Springer.CrossRefGoogle Scholar
  17. Raja Rao, C. S. (1970). Sequence, structure and correlation of the metasediments and gneisses of the BGC of Rajasthan. Records Geological Survey of India, 98(2), 122–131.Google Scholar
  18. Roy, A. B., & Kröner, A. (1996). Single zircon evaporation ages constraining the growth of the Archaean Aravalli craton, northwestern Indian shield. Geological Magazine, 133, 333–342.CrossRefGoogle Scholar
  19. Roy, A. B., Kroner, A., & Laul, V. (2001). Detrital zircons constraining basement age in a late Archaean greenstone belt of southeastern Rajasthan, India. Current Science, 81(4), 407–410.Google Scholar
  20. Sahoo, K. C., & Mathur, A. K. (1991). On the occurrence of Sargur type banded iron formation in Banded Gneissic Complex of south Rajasthan. Journal of the Geological Society of India, 38, 299–302.Google Scholar
  21. Sarkar, G., Ray, Burman T., & Corfu, F. (1989). Timing of continental arc type magmatism in northwest India: Evidence from U-Pb zircon geochronology. The Journal of Geology, 97, 607–612.CrossRefGoogle Scholar
  22. Sharma, R. S. (1988). Patterns of metamorphism in the Precambrian rocks of the Aravalli mountain belt. In A. B. Roy (Ed.), Precambrian of the Aravalli Mountains, Rajasthan, India (Vol. 7, pp. 33–76). Memoir Geological Society of India.Google Scholar
  23. Sharma, R. S. (1995). An evolutionary model for the Precambrian crust of Rajasthan: Some petrological and geochronological considerations. Memoir Geological Society of India, 31, 91–115.Google Scholar
  24. Sinha-Roy, S. (1985). Granite–greenstone sequence and geotectonic development of SE Rajasthan. Bulletin Geological Mining and Metallurgical Society India, 53, 115–123.Google Scholar
  25. Sinha-Roy, S., Guha, D. B., & Bhattacharyya, A. K. (1992). Polymetamorphic granulite facies pelitic gneisses of the Precambrian Sandmata Complex, Rajasthan, India. Indian Minerals, 46, 1–12.Google Scholar
  26. Thompson, A. B. (1976). Mineral reactions in pelitic rocks: II-calculation of some P-T-X (Fe-Mg) phase relation. American Journal of Science, 276, 425–454.CrossRefGoogle Scholar
  27. Upadhyaya, R., Sharma, B. L., Jr., Sharma, B. L., Sr., & Roy, A. B. (1992). Remnants of greenstone sequence from the Archaean rocks of Rajasthan. Current Science, 63, 87–92.Google Scholar
  28. Wiedenbeck, M., & Goswami, J. N. (1994). High precision 207Pb/206Pb zircon geochronology using a small ion microprobe. Geochimica et Cosmochimica Acta, 58, 2135–2145.CrossRefGoogle Scholar
  29. Wiedenbeck, M., Goswami, J. N., & Roy, A. B. (1996). Stabilization of Aravalli craton of the north-western India at 2.5 Ma: An ion microprobe zircon study. Chemical Geology, 129, 325–340.CrossRefGoogle Scholar
  30. Winkler, H. G. F. (1974). Petrogenesis of metamorphic rocks (3rd ed., p. 320). New York: Springer.CrossRefGoogle Scholar

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© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Geological Survey of IndiaJaipurIndia

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