Metamorphic evolution of the contact aureole of the Jhirgadandi pluton, Sonbhadra district,Mahakoshal mobile belt, central India

Journal of Earth system science

Anand K Srivastava2³  S P Singh1⁴  Gopendra Kumar3²  S B Dwivedi4¹ 

[1] Department of Civil Engineering, Indian Institute of Technology (BHU), Varanasi 221 005, India.$$;Formerly, Geological Survey of India, B58, Kendriya Vihar Apartment, Sector 6, Jankipuram Vistar, Lucknow 226 021, India.$$;Formerly, Department of Geology, Lucknow University, 124 Kashipur House, Aryanagar, Lucknow 226 004, India.$$;Department of Geology, Institute of Earth Science, Bundelkhand University, Jhansi 284 128, India.$$

关键词: Contact aureole;    geothermobarometry;    hornfels texture;    Jhirgadandi pluton;    superimposed metamorphism.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

The metamorphic evolution of the contact aureole around the Late Paleoproterozoic Jhirgadandi pluton in the eastern part of Parsoi Formation of Mahakoshal terrain, central India represents three distinct metamorphic zones, characterized by definite mineral assemblages. The contact-metamorphic event produced the peak-metamorphic mineral assemblages Bt + Qtz + Alb + Sil ± Cd ± Grt ± Mus ± Kfs in the metapelites of inner aureole, Bt + Qtz + And + Mus + Kfs + Plag ± Cd ± Chl in middle aureole and Chl + Mus + Bt ± And + Alb + Qtz ± Ep + Mt ± tourmaline in the outer aureole. The estimated P–T conditions based on detailed geothermobarometric calculations in the thermal metamorphosed rocks are 690°C/3.4 kbar, 580 ± 15°C and 487 ± 30°C in inner aureole, middle aureole and outer aureole, respectively. The variation in metamorphic condition suggests that the shallow crustal level emplacement of Jhirgadandi pluton is responsible for the overprinting of contact metamorphic assemblages (M2) in the low grade metapelites (regional metamorphism M1) of Mahakoshal Group.

【 授权许可】

Unknown