Frontier Exploration of the Deepwater Indus Fan Basin, Pakistan

Richard Tozer¹, Shakeel Akhter¹, John Bennett¹, Scott Carmichael¹, Richard Corfield¹, Mansoor Fatimi¹, Robert Jones¹, and Mark Longacre^2
1BP Exploration & Production, Sunbury on Thames, United Kingdom
²MBL inc., Denver, CO

The deepwater Indus Fan Basin is located on the NW passive margin of the Indian Subcontinent. The basin is under-explored with only 2 wells drilled offshore Pakistan and 5 offshore NW India in water depths greater than 1000m. New 2D seismic reflection lines acquired during 2007/8, together with existing potential field and well data, have allowed a new assessment of hydrocarbon potential and exploration risk in this frontier area.

Rifting between India and the Seychelles began during the Late Cretaceous and was followed by separation and ocean spreading in the Late Cretaceous - Early Paleocene. This event is associated with the extrusion of large volumes of volcanic rock which infill the late rift structure and strongly mask the underlying Late Cretaceous rift geometries. These volcanic rocks are equivalent in age and thickness to the Deccan volcanics onshore. During the Paleocene and early Eocene, isolated carbonate reefs developed on bathymetric highs above the offshore volcanic edifice. These were flanked by deep water, sediment starved basins. This pattern of sedimentary facies changed dramatically during the middle Eocene when formation of the Himalayas and establishment of the Indus River resulted in a major increase in clastic sediment input. This continued in the Oligocene and throughout the Neogene, and up to 9000m of clastic sediment is present; spectacular Neogene channel-levee systems represent potential reservoir targets. The key challenge for future exploration is to determine whether source rocks are present in sufficient quality and quantity for commercial discoveries.

Presentation GEO India Expo XXI, Noida, New Delhi, India 2008©AAPG Search and Discovery