The Regional Stratigraphic and Depositional Setting of the Paleocene-Eocene Coal-Bearing Rocks of South Sindh, Pakistan

Peter D. Warwick, Roger E. Thomas

Subsurface data from more than 150 coal, oil, and gas exploration drill holes, seismic data, and palynological data from southeastern Pakistan, were incorporated into a regional stratigraphic and depositional model which can be used to explain the distribution of coal deposits in the region.

Preliminary stratigraphic correlations indicate that the Paleocene-Eocene-age coal deposits of Lakhra and Sonda coal fields and the recently discovered Thar coal field in southern Sindh Province are part of a time-transgressive regional sequence that culminates with the deposition of Eocene-age coal-bearing strata in western India. The coal-bearing strata of the Paleocene Bara Formation in the Lakhra-Sonda area of southwestern Sindh were deposited in near-shore mires that formed in a subsiding basin during a relative low stand. The Thar coal deposit, which contains about 88 percent of the 90 billion tonnes of coal resources estimated for Pakistan, was deposited in near-shore mires that were parallel to an exposed terrain of granitic basement rocks. These faulted basement rocks, which re exposed in the Nargar Parkar area in southeastern Pakistan, directly underlie the coal-bearing interval in parts of the Thar coal field. The Eocene-age lignite-bearing rocks of western India appear to have been deposited in restricted depressions within the granitic terrain during a relative high stand. Common intercalations of marine sediments into the coal-bearing intervals in Pakistan indicate that the transgression was not continuous but that it fluctuated through time.

AAPG Search and Discovery Article #91020©1995 AAPG Annual Convention, Houston, Texas, May 5-8, 1995