Late Oligocene climate and floristic diversity of Assam, Northeast India


  • Harshita Bhatia Birbal Sahni Institute of Palaeosciences, 53 University Road, Lucknow 226 007, India
  • Gaurav Srivastava Birbal Sahni Institute of Palaeosciences, 53 University Road, Lucknow 226 007, India
  • R.C. Mehrotra Birbal Sahni Institute of Palaeosciences, 53 University Road, Lucknow 226 007, India



Fossils, CLAMP, Monsoon, Oligocene, Palaeoclimate


Late Oligocene is considered as the last significant globally warm climate. In India, the Makum Coalfield has exposures of sediments which were deposited at a low latitude of 10–15° N during the late Oligocene. Here, we report a diverse assemblage of fossil leaves and fruits. The assemblage envelops 18 leaf and 9 fruit morphotypes. The floristic assemblage indicates a warm and humid climate during the deposition of the sediments. The quantitative palaeoclimate reconstruction indicates that the leaf morphological traits were dominantly adapted to Indonesian–Australian type of monsoon.


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How to Cite

Bhatia, H., Srivastava, G., & Mehrotra, R. (2021). Late Oligocene climate and floristic diversity of Assam, Northeast India. Journal of Palaeosciences, 69, 73–92.



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