Structural Imaging of Daman Pay in the Presence of Overlying Carbonate Build-Up: A Case Study from B9 Area of Mumbai Offshore Basin
- Debakanta Biswal (Adani Welspun Exploration Limited) | Nasimudeen Nedeer (Adani Welspun Exploration Limited) | Subrata Banerjee (Adani Welspun Exploration Limited) | Kumar Hemant Singh (Indian Institute of Technology)
- Document ID
- Society of Petroleum Engineers
- SPE Oil and Gas India Conference and Exhibition, 9-11 April, Mumbai, India
- Publication Date
- Document Type
- Conference Paper
- 2019. Society of Petroleum Engineers
- 5.1.8 Seismic Modelling
- Carbonate Build-up, Structural Imaging, Layer Cake Depth Conversion, Structural Configuration, Velocity Pull-up
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- 48 since 2007
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The boundary between a thick carbonate layer and its substrata is often a well-defined reflector due to the presence of shaly and clayey layers beneath the carbonates. This reflector and other underlying reflectors result in a velocity pull-up effect because the seismic velocities within the carbonates are higher than that of the surrounding sediments. The geometry of velocity pull-up beneath the carbonate body is related to the geometry of the structure and the thickness of the carbonate body the seismic wave travels through.
In B9 area of Mumbai Offshore basin, the reservoir facies are largely represented by clastics deposited along tidal deltaic lobes. Wells drilled though Daman formation have encountered good quality pay sands within the Daman formation. This pay has produced commercial quantities of hydrocarbons in the vicinity making the area attractive for further exploration and exploitation. The overlying Bombay formation consists mainly of shale with occasional bands of limestone and claystone. The development of thick isolated carbonates bodies within Bombay formation is observed in "C" structure on which "Well-C" is placed. This is seen to significantly constrain the structural configuration in the "C" area. There is a possibility of substantial extension of the "C" structure towards south if the impact of velocity pull up due to carbonate build up can be successfully mitigated. The ultimate challenge is to image the Daman reservoirs, mitigating overburden lateral velocity variations.
In addition to a layered cake depth conversion approach for depth conversion of the time map, a more robust approach, PSDM followed by depth conversion was carried out. This paper highlights the merit of different methods.
|File Size||2 MB||Number of Pages||13|
Biswal, S. K., Harilal, Vachak, H. S., Rawat, D. S., Bhagat, S., Bharsakale, A., Tandon, A. K., (2012); Deliberate Search for Stratigraphic Traps within Oligocene Sediments of Central Graben in the Western Offshore Basin, India. 10th Biennial International Conference & Exposition, Society of Petroleum Geophysicists, Hyderabadi, India
Pande, J. P., Singh, K. R. K., Singh, M., Kalaiarasan, T., Mukherjee, R. N., Marathe, U. G., (2013); Late Oligocene Sandstone reservoirs of Saurashtra Offshore, significance of their deposition – An Integrated study resulting in regional clastic model; 10th Biennial International Conference & Exposition, Society of Petroleum Geophysicists, Kochi, India.
Singh, B. K., Satyanarayana, P. V. V., Nambiar, K. R., Marathe, U. G., (2013); Delineation of Thin Reservoir Pay Sand and it’s Prediction in Saurashtra Dahanu Area, Western Offshore Basin, India-A Case Study; 10th Biennial International Conference & Exposition, Society of Petroleum Geophysicists, Kochi, India.