Structural and stratigraphic interpretation of 2D seismic data of Kadanwari area (P-1114) (MFN 3597)

Abstract

The Kadanwari block study area is located 350 km NE of Karachi in the Khairpur District Sindh. It is part of Gondawanian domain and lies in the Middle Indus Basin of Pakistan. Kadanwari gas field is situated on the south eastern shoulder of Khairpur High. The area has been known to be prone for sweet gas production. Sembar formation of Cretaceous age is proven the source rock in the area; Lower Goru sands and upper Goru shaly sequence of lower cretaceous age are proven reservoir and seal respectively for hydrocarbons discovered in Kadanwari gas field. Stratigraphy and structural setting of Kadanwari block are described by interpreting 2D seismic data. Four seismic lines from Tajjal area namely TJ89 – 520, TJ89 – 524, TJ90 – 709 & TJ91 – 803 along with Gorwar-01 well were utilized for this purpose. The main objective of the study is to understand the structural style and identifying the potential leads, their extension and nature of structure providing closure for hydrocarbons at reservoir level. To achieve this objective structural interpretation on all the four lines is done which includes identification of horizons and faults on seismic section by careful marking on the basis of acoustic response of underneath earth. TWT contour maps and Depth contour maps are generated to determine and verify the traps identified on seismic section. Potential leads are identified at Lower Goru (Intra-cretaceous 1 & Intra-cretaceous 2), Basal Sands and Massive Sands of lower cretaceous age. Study area lies in transitional regime with associated normal faults; creating negative flowering structures. These faults are mainly responsible for structural traps in the study area. The reservoir is compartmentalized which provides interesting opportunity for development. Clearer image of subsurface can be generated by good quality 3D data.