PALYNOSTRATIGRAPHIC STATUS AND DEPOSITIONAL ENVIRONMENT OF GIRUJAN CLAY AND DUPITILA FORMATION EXPOSED ALONG SHARI RIVER (DIGRAIL) AND DUPIGAON, SYLHET, BANGLADESH

S. K.  Saha; R.Y.  Singh

doi:10.53808/KUS.2000.2.2.0045-L

Authors

S. K. Saha Environmental Science Discipline, Khulna University, Khulna 9208, Bangladesh
R.Y. Singh Centre of Advanced Studies in Geology, Panjab University, Chandigarh 160014, India

DOI:

https://doi.org/10.53808/KUS.2000.2.2.0045-L

Keywords:

Girujan clay; DupiTila; Palynostratigraphy; Pliocene; Pleistocene; Sylhet; Bangladesh

Abstract

The Girujan Clay Formation is demarcated as Bangladeshopollenites barishalensis Zone, which is equivalent to middle-upper Siwalik sediments of Punjab Basin. The mangrove and coastal palynotaxa present in this formation indicate that these sediments have been deposited under the delta condition in a supratidal environment. The Girujan Clay Formation is considered to be of Mio-Pliocene in age. The DupiTila Formation is recognized here as Corrugatisporites sp. Zone. This formation is equivalent to Namsang bed of Assam-Meghalaya region. The palynological assemblage of this formation is suggestive of a high degree of precipitation and the presence of rainfed river system prevailing in the basin of deposition. It is of Plio-Pleistocene in age.

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