April 13th, 2023 DGS Luncheon Presentation – Sagnik Dasgupta, SLB

Comprehensive lithological description, reservoir property and pore pressure prediction for unconventional shale reservoirs using rock physics: Midland reservoir characterization study

Sagnik Dasgupta

Abstract:

Unconventional reservoirs are generally found to be primarily heterogeneous and with complex minerology. Variations in production at different stages from the same horizontal wells clearly demonstrate the complexity of these source rocks. Inversion of seismic data plays a critical role in understanding this spatial variability. Identification of lateral variations of elastic lithofacies, associated mineralogical composition, kerogen and porosity can be achieved by integrating rigorous rock physics models with seismic inversion results. Reservoir pressures in this kerogen rich source rock is another crucial property for successful production. As generation of hydrocarbons from kerogen and the associated volume expansion makes such pressures develop, high resolution pore pressure estimation helps to identify the reservoir quality and possible completion strategy for such cases. Herein, we present results of lithoclassification as well as reservoir property and pore pressure prediction, all derived from elastic parameters of input prestack Amplitude-Variation-with Angle (AVA) inversions from the Midland Basin, in West Texas.

Sagnik Dasgupta is a Senior rock physicist at SLB (Houston, Texas). He has worked at SLB for 16 years and has been in the field of rock physics for the last 14 years. As a rock physicist, he has worked different projects both onshore and offshore from China, Malaysia, India, Kuwait, Nigeria, Egypt, and Argentina and presently is working on different projects in the US, Canada, and Mexico. He received his M.Sc. and M.Tech. degree in geosciences from the Indian Institute of Technology Bombay (India). His main interests are rock physics, petrophysics, geophysics and geomechanics, bringing different data from different disciplines to understand the behavior of rocks. He has published several papers in different geophysical societies and is an active member of SEG and GSH.