Abstract: Structure and Hydrocarbon Exploration in the Southern Portion of the Sulaiman Range Fold and Thrust Belt, Pakistan

Thom L. Davis, Jay Namson, David A. C. Clark, Dudley R. Seifert

Recent hydrocarbon exploration in the southern portion of the Sulaiman Range fold and thrust belt adds new insights into the structural framework and hydrocarbon potential of this relatively unexplored region. New data collected during the last three years consist of field mapping, seismic reflection profiles and source rock samples. These new data have been integrated with a considerable body of older data and require modification of an earlier thrust-wedge model developed by Banks and Warburton. These data also show the area to have considerable gas and oil potential. Field relationships and interpretations of seismic profiles show that convergence within the inner part of the belt is early Eocene in age, and Miocene and younger in the outer part of the belt. Eocene age thrust flats occur near the base of the Jurassic carbonate sequence and within the lower part of the Eocene Ghazij Formation and are south-vergent. Backthrusts, stepping up from the base of the Jurassic, are common but do not seem to connect into a north-vergent regional passive-roof thrust as in the thrust-wedge model. Rather, excess south-directed thrust slip comes to the surface or is truncated along an Oligocene age unconformity. Late Cenozoic thrusts rarely reach the surface. These thrusts step up from the base of the Jurassic carbonate sequence and thrust slip is consumed making very large fault-propagation folds. Several oil seeps and a well test (3-7 MMcfd) indicate hydrocarbons have been generated within the belt. The lower portion of the Lower Cretaceous Sembar Formation is the most likely ource of gas and oil based on field samples with total organic content between 1.00-2.5.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994