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Genesis of Epidiorites Associated with Dhalbhum Formation of Proterozoic Singhbhum Basin

  • Vidyanand Bhagat
  • Vikash KumarEmail author
Chapter
Part of the Society of Earth Scientists Series book series (SESS)

Abstract

Epidiorites occurring as conspicuous bands and sill-like bodies interstratified with schistose rocks of Dhalbhum Formation, belonging to Proterozoic Singhbhum Group, are rocks of enigmatic nature characterized by volcanic flows associated with tuffs and other volcaniclastic materials, the genesis of which has so far remained a matter of debate. They are very fine-grained, less schistose with irregular joints, partings and splintery habits. Petrographically, they are characterized by greenschist facies mineralogy represented by albite–epidote–chlorite ± actinolite assemblages similar to the Dalma rocks occupying the mid basinal part of the Singhbhum mobile belt but with higher proportion of saussuritized plagioclase and sericitized K-feldspar often containing oval and elliptical bombs and tephra of glassy matters revealing their tuffaceous character. Their overall compositional homogeneities and other chemical attributes indicate their tholeiitic to calc-alkaline nature. Some of them show very close chemical proximity with the Dalma metavolcanic rocks which are characterized by exceedingly low-K tholeiites comparable to oceanic abyssal tholeiitic basalts falling within the chemical spectrum of enriched MORB ranging in composition from mafic to somewhat ultramafic lavas. The various chemical trends amply suggest that epidiorites are the late differentiates of Dalma parental magma ranging in composition from basalt–basaltic trachy andesite–trachy andesite following the iron suppressed calc-alkaline line of descent. The MORB and Chondrite normalized patterns showing more spiky nature in contrast to relatively smooth patterns of Dalmas are also suggestive of their more evolved nature. Enrichment of LREE (~7xHREE), higher range of total REE (200–434 ppm) as well as (La/Sm)N (3.45–4.78) and (La/Yb)N (7.81–11.60) also indicate their fractionated character. A distinctive negative Eu-anomaly marks the REE patterns of the more felsic epidiorites. A narrow range of variation in Ce/Nd ratio in Dalma metavolcanics (1.26–1.55) and epidiorites (1.80–2.49) together with Mg number (58–74) and FeO0/MgO (0.85–1.59) suggest their comagmatic character. The enriched MORB composition and bimodal mafic to ultramafic effusion of Dalma rocks are specific of back-arc extensional tectonic regime showing signs of violent eruptive nature both subaerial and subaqueous. Dalmas as well as the epidiorites with 4–5% MgO simulate the common chemical features of the back-arc basalt from East Scotia basin in south Atlantic. The study of epidiorites assumes significance as components of Dalma volcanics are also found within the Dhalbhum succession. The larger implication of the work has suggested that the volcanic dominated Singhbhum Group of rocks resemble the Precambrian greenstone associations related to island-arc assemblages.

Keywords

Epidiorites Dhalbhum formation Dalma volcanics Tholeiites Calc-alkaline Back-arc basin 

References

  1. Arculus, R. J., & Powell, R. (1986). Source component mixing in the regions of arc magma generation. Journal of Geophysical Research, 91, 5913–5926.CrossRefGoogle Scholar
  2. Bose, M. K. (1994). Sedimentation pattern and tectonic evolution of the Proterozoic Singhhum basin in the eastern Indian Shield. Tectonophysics, 23, 325–346.CrossRefGoogle Scholar
  3. Bose, M. K. (2000). Mafic-ultramafic magmatism in the eastern Indian craton–a review. Geological Survey of India Special Publication, 55, 227–258.Google Scholar
  4. Bose, M. K., & Chakraborti, M. K. (1981). Fossil marginal basin from the Indian shield: A model for the evolution of Singhbhum Precambrian belt, Eastern India. Geologische Rundschau, 70, 504–518.CrossRefGoogle Scholar
  5. Chakraborti, M. K., & Bose, M. K. (1985). Evaluation of the tectonic setting of Precambrian Dalma volcanic belt, eastern India, using major and trace element characters. Precambrian Research, 28, 253–268.CrossRefGoogle Scholar
  6. Chatterjee, P., De, S., Ranaivoson, M., Mazumder, R., & Arima, M. (2013). A review of the ~1600 Ma sedimentation, volcanism and tectono-thermal events in the Singhbhum craton, Eastern India. Geoscience Frontiers, 4(3), 277–287.CrossRefGoogle Scholar
  7. Condie, K. C. (1989). Geochemical changes in basalts and andesites across the Archaean-Proterozoic boundary: Identification and significance. Lithos, 23, 1–18.CrossRefGoogle Scholar
  8. Crawford, A. J., Beccaluva, L., & Serri, G. (1981). Tectonomagmatic evolution of the west Phillipine—Mariana region and the origin of boninites. Earth and Planetary Science Letters, 54, 346–356.CrossRefGoogle Scholar
  9. Dasgupta, H. C., &  Mishra, S. (2005). Petrogenesis of Hudupahar Gitilgarh Metabasic Rocks in Chotanagpur Granite Gneiss. Journal of the Geological Society of India, 66(1), 66–80.Google Scholar
  10. Davidson, J. P. (1996). Deciphering mantle and crustal signatures in subduction zone magmatism. In G. E. Bebout, D. W. Scholl, S. H. Kirby, & J. P. Platt (Eds.), Subduction top to bottom (Vol. 96, pp 251–262). American Geophysical Union Geophysical Monograph.CrossRefGoogle Scholar
  11. Dunn, J. A., & Dey, A. K. (1942). The Geology and Petrology of Eastern Singhbhum and surrounding areas. Memoirs of the Geological Survey of India, 69(2), 281–456.Google Scholar
  12. Dwivedi, A. K., Pandey, U. K., Murugan, C., Bhatt, A. K., & Ramesh Babu, P. V. (2011). Geochemistry and geochronology of A-type Barabazar Granite: Implications on the geodynamics of South Purulia Shear Zone, Singhbhum Craton. Journal of the Geological Society of India, 77, 527–538.CrossRefGoogle Scholar
  13. Engel, A. E. J., Engel, C. G., & Havens, R. G. (1965). Chemical characteristics of oceanic basalts and the upper mantle. Bulletin of the Geological Society of America, 76, 719–725.CrossRefGoogle Scholar
  14. Eriksson, P. G., Mazumder, R., Catuneanu, O., Bumby, A. J., & Ountsche Ilondo, B. (2006). Precambrian continental freeboard and geological evolution: A time perspective. Earth-Science Reviews, 79, 165–204.CrossRefGoogle Scholar
  15. Grove, T. L., & Baker, M. B. (1984). Phase equilibrium controls on the tholeiitic versus calc-alkaline differentiation trends. Journal of Geophysical Research, 89, 3253–3274.CrossRefGoogle Scholar
  16. Gupta, A., & Basu, A. (1979). On the occurrence of pillow lavas in Dalma metavolcanic suite, Singhbhum and Ranchi districts, Bihar. Journal of the Geological Society of India, 20, 42–44.Google Scholar
  17. Gupta, A., Basu, A., & Singh, S. K. (1977). Occurrence of a pyroclastic conglomerate in Dalma metavolcanics, Singhbhum district, Bihar. Indian Journal of Earth Sciences, 4(2), 160–168.Google Scholar
  18. Hart, S. R., & Blusztajn, J. (2006). Age and geochemistry of the mafic sills, ODP site 1276, Newfoundland margin. Chemical Geology, 235, 222–237.CrossRefGoogle Scholar
  19. Hawkesworth, C. J., & Powell, M. (1980). Magma genesis in the Lesser Antilles island arc. Earth and Planetary Science Letters, 51, 297–308.CrossRefGoogle Scholar
  20. Hirose, K., & Kawamoto, T. (1995). Hydrous partial melting of lherzolite at 1GPa: The effect of H2O on the genesis of basaltic magmas. Earth and Planetary Science Letters, 133, 463–473.CrossRefGoogle Scholar
  21. Jensen, L. S. (1976). A new cation plot for classifying sub-alkalic volcanic rocks. Miscellaneous paper (Ontario Division of Mines), Vol. 66, p22.Google Scholar
  22. Karig, D. E. (1971). Origin and development of marginal basins in the western Pacific. Journal Geophysical Research, 76, 2542–2561.CrossRefGoogle Scholar
  23. Keith, S. B. (1978). Palaeosubduction geometries inferred from cretaceous and tertiary magmatic patterns in south western south America. Geology, 6, 516–521.CrossRefGoogle Scholar
  24. Kumar, V. (2014). Stratigraphic status of the Koderma Mica belt vis-a-vis the tectonic evolution of amphibolites of the Chotanagpur region. IJEE, 7(4), 764–774.Google Scholar
  25. Le Maitre, R. W. (2002). Igneous rocks: A classification and glossary of terms (2nd ed., p. 236). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
  26. Mazumder, R. (2005). Proterozoic sedimentation and volcanism in the Singhbhum crustal province, India and their implications. Sedimentary Geology, 176, 167–193.CrossRefGoogle Scholar
  27. Mazumder, R., & Altermann, W. (2009). A brief overview of Paleoproterozoic geology of the Singhbhum Crustal Province, Eastern India. Rep IGCP 509. http://earth.yale.edu/sites/default/files/files/IGCP/SinghbhumRepIGCP(1).pdf.
  28. McBirney, A. R. (1996). The Skaergaard intrusion. In R. G. Cawthorn (Ed.), Layered intrusions (pp. 147–180). New York: Elsevier.CrossRefGoogle Scholar
  29. McDonough, W. F., & Sun, S. S. (1995). The composition of the Earth. Chemical Geology, 120, 223–253.CrossRefGoogle Scholar
  30. Miyashiro, A. (1974). Volcanic rock series in island arcs and active continental margins. American Journal of Science, 274(4), 321–355.CrossRefGoogle Scholar
  31. Pearce, J. A. (1983). Role of sub-continental lithosphere in magma genesis at active continental margins. In C. J. Hawkesworth & M. J. Norry (Eds.), Continental basalts and mantle xenoliths (pp. 230–249). Cheshire: Shiva Publ.Google Scholar
  32. Powell, R. (1978). Thermodynamics of rock and fluid systems: Equilibrium thermodynamics in petrology (p. 283). New York: Harper and Row.Google Scholar
  33. Sarkar, S. N., & Saha, A. K. (1962). A revision of the Precambrian stratigraphy and tectonics of Singhbhum and adjacent regions. Quarterly Journal Geological, Mining and Metallurgical Society of India, 34(2&3), 97–136.Google Scholar
  34. Saunders, A. D., & Tarney, J. (1979). The geochemistry of basalt from back-arc spreading center in the East Scotia sea. Geochimica et Cosmochimica Acta, 43, 555–572.CrossRefGoogle Scholar
  35. Schmidt, M. W., & Poli, S. (1998). Experimentally based water budgets for dehydrating slabs and consequences for arc magma generation. Earth and Planetary Science Letters, 163, 361–379.CrossRefGoogle Scholar
  36. Shao-Cong Lai. (2007). Geochemistry and tectonic significance of the ophiolite associated volcanics in the Mianlue Suture, Qinling Orogenic belt, China. Journal-Geological Society of India, 70, 217–234.Google Scholar
  37. Shirley, D. N. (1987). Differentiation and compaction in the Palisades sill, New Jersey. Journal of Petrology, 28, 835–865.CrossRefGoogle Scholar
  38. Shuguang, L. (1993). Ba-Nb-Th-La diagrams used to identify tectonic environments of ophiolite. Acta Petrlogica Sinica, 9, 146–157.Google Scholar
  39. Sugimura, A. (1968). Spatial relations of basaltic magmas in island arcs. In H. Hess & A. Poldervaart (Eds.), Basalts 2 (pp. 537–571). New York: Interscience.Google Scholar
  40. Sun, S. S., & McDonough, W. F. (1989). Chemical and isotopic systematics of ocean basalts: Implication for mantle composition and processes. Geological Society, London, Special Publications, 42, 313–345.CrossRefGoogle Scholar
  41. Tarney, J., Saunders, A. D. & Weaver, S. D. (1977). Geochemistry of volcanic rocks from the island arcs and marginal basins of the Scotia Arc region. In M. Talwani & W. C. Pitman (Eds.), Island arcs, Deep sea trenches and back-arc basins (pp. 367–377). American Geophysical Union.CrossRefGoogle Scholar
  42. Thompson, R. N., Morrison, M. A., Hendry, G. L., & Parry, S. J. (1984). An assessment of the relative roles of a crust and mantle in magma genesis: An elemental approach. Philosophical Transactions of the Royal Society of London, A, 310, 549–590.Google Scholar
  43. Wilson, M. (1989/97). Igneous petrogenesis (a global tectonic approach). Chapman and Hall: London. 466 p.Google Scholar
  44. Wones, D. R., & Eugster, H. P. (1965). Stability of biotite: Experiment, theory, and application. American Mineralogist, 50, 1228–1272.Google Scholar

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© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Geology (CE)Muzaffarpur Institute of TechnologyMuzaffarpurIndia

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