Abstract: Mesozoic and Cenozoic History and Hydrocarbon Potential of Sulaiman Range, Central Pakistan

WAHEED, ABDUL

Sulaiman Range is a N-S fold-thrust belt, which rises abruptly from plains west of Indus River. In its central areas, the range exposes 6000 meters of Jurassic to Eocene rocks and several kilometers of younger molasse crop out in its eastern foothills. The Cretaceous paleogeography agrees with a pre-orogenic, west-facing, open-marine shelf on which carbonates and later clastics (derived from craton in the east) were deposited. Early Tertiary sedimentation was broadly dominated by carbonates (shelf, reef, slope facies). However, during Paleocene and Eocene, clastic deposition occurred in certain parts of the Sulaiman Range. These clastic influxes from north and northwest indicate uplift of the shelf due to oblique collision between Indo-Pakistan plate with SE Afghanistan microplate. In the later period of Himalayan Orogeny during Miocene and Pliocene, coarsening-upward molasse was deposited in foredeeps by longitudinal and transverse rivers flowing toward south and southeast.

Several gas and gas/condensate fields have been discovered in Sulaiman Range. Mature source rocks are known to exist in the Mesozoic sequence. Good-quality clastic and carbonate reservoirs are present within Cretaceous, Paleocene and Eocene rocks. Large structures (simple folds, faulted folds), which post-date the main hydrocarbon generation phase, are targets for future drilling and hold promise for large discoveries. Case histories of several fields will be presented.

AAPG Search and Discovery Article #90942©1997 AAPG International Conference and Exhibition, Vienna, Austria