Abstract:
This dissertation contains the study and interpretation of 2D seismic reflection data of
selected seismic lines of Sinjhoro area, Lower Indus Basin, Pakistan. The main objective
of this research was delineation of subsurface structures favorable for hydrocarbon
accumulation and attributes analysis.. This area is situated in the Sanghar District of
Sindh Province and is licensed to Oil and Gas Development Corporation Limited
(OGDCL). The seismic data for this dissertation was provided by the Land Mark
Resources (LMKR) by the permission of Directorate General of Petroleum Concessions
(DGPC). The data comprised six seismic lines, well tops of well CHAK 63-01, CHAK
66-01 and CHAK 7A-01. The names of lines obtained are: (20017-SNJ-03, 20017-SNJ-
04, 20017-SNJ-05, 20017-SNJ-07, 20017-SNJ-08 and 20017-SNJ-20). Six horizons are
marked and named after correlating with well tops of CHAK 66-01, after well to seismic
tie these horizons are correlated in whole area. In time structure maps, it was found that
the area is under the Extensional Tectonic Regime which produced the Normal faulting in
the region. Major Horst and Graben structures are formed due to process of rifting After
Cretaceous only single major fault extends up to Chiltan Formation of Jurassic age. The
lower cretaceous shale of sember formation is proven source for oil and gas discovered in
the lower Indus basin, The Basal Sands of Lower Goru Formation are the main zones of
interest in this area the upper goru formation as well as shale within the lower goru
formation serves as cap rock for the underline sandstone reservoir. Time and depth
contours were generated to for structural delineation. Seismic attributes are applied to
identify the lithological distribution, structural deformation of the strata and for
identifying the presence of hydrocarbon in the area. Instantaneous frequency attributes
are used for the purpose of identifying the lithological distribution and their lateral
discontinuities. Variance attribute is used for identification of the structural deformation,
whereas envelope attribute is used to mark the possible location for hydrocarbon
presence. The hydrocarbon potential of CHAK 66-01and CHAK 63-01is calculated by
evaluating their petrophysical analysis of the Well logs.
