Analysis of the Sediments from the Subsurface of the Bogra Area, Bengal Basin, East Pakistan: ABSTRACT

Abstract

The Bengal Basin, located in East Pakistan and neighboring India, contains a stratigraphic section which can best be described as a basin-delta complex. Formations ranging in age from Gondwana (Upper Paleozoic) to Recent have been studied in cuttings and core samples from two dry tests. The samples were described and some were analyzed either mechanically or chemically. Conclusions are that both the tectonic and the resulting sedimentary environments varied considerably during the deposition of this section. The older sediments deposited prior to the principal Himalayan orogenies were nonmarine. They differ greatly in lithologic character and in thickness. They were influenced by volcanic activity and continental glaciation. The Sylhet limestone (Eocene) can be interpreted as having originated in a fairly uniform marine environment. The growth of the Himalayas initiated a new and significant source of sediments and fluviatile and deltaic agencies of deposition predominated as they do at present. The Sylhet limestone has yielded gas from several pools and appears to be the most likely, if not the only, possibility for future discoveries of hydrocarbons. However, there may be other marine deposits to the south, closer to or underlying the Bay of Bengal. End_of_Article - Last_Page 357------------