Rock Physics Analysis, Seismic and Well Log Interpretation for The Evaluation of Reservoir Properties of Basal Filed, Upper Indus Basin, Pakistan

Abstract

Basal oil field is an exclusive Development & Production Lease of Oil and Gas development corporation, was discovered in 1999 by OGDCL. 2-D seismic survey was done in the area in 1999. It is situated about 77 km Northwest of Islamabad and it lies in Attock District. Basal oil field lies in Basal block bounded by latitudes 33° 28' 39" N to 72° 11° 40" E. Main emphasis of the present work is the application of 2-D structural analysis based on integrated techniques of seismic and well log and rock physics analysis in Basal area, Pakistan. The seismic reflection data of the study area and well logs of Garhi-X-01 well is provided by LMKR with the prior approval from the Directorate General of Petroleum Concession (DGPC) Pakistan. Seismic data interpretation has been performed on given seismic lines by marking reservoir horizons of Chorgali Formation, Sakesar Formation, Nammal Formation, Patala Formation and Lockhart Formation by using formation tops. Structural interpretation of the area is done after making time and depth contours of Chorgali, Sakesar, Nammal, Patala and Lockhart formation after picking time and their time to depth conversions. Rock physics analysis and geosesimic section was drawn to understand the lithological character and possible hydrocarbon zones in Lockhart Formation got marked by viewing cross-over effects in logs of these Formations. Petrophysical analysis got performed on the log data of Lockhart Formation by using different log formulae, Graphs of pay zone have made them easy to interpret the hydrocarbon prospect of Chorgali and Lockhart Formations. Results of seismic and Petrophysical analyses claim that, pop-up anticlinal structure is formed in the understudy area and there is one pay zone in Lockhart Formation of Garhi-0X-01 well.