Seismic and Rockphysics Diagnostics of Multiscale Reservoir Textures Quarterly Report (open access)

Seismic and Rockphysics Diagnostics of Multiscale Reservoir Textures Quarterly Report

As part of our study on ''Relationships between seismic properties and rock microstructure'', we have continued our work on analyzing microstructural constraints on seismic signatures. Our analysis is now extended to over 280 images of shales, giving us better statistics. The shales cover a range of depths and maturity. We estimate different statistical measures for characterizing heterogeneity and textures from scanning acoustic microscope (SAM) images of shale microstructures. Characterizing and understanding the microgeometry, their textures, scales, and textural anisotropy is important for better understanding the role of microgeometry on effective elastic properties. We analyzed SAM images from Bakken shale, Bazhenov shale, and Woodford shale. We observed quantifiable and consistent patterns linking texture, shale maturity, and elastic P-wave impedance. The textural heterogeneity and P-wave impedance increase with increasing maturity (decreasing kerogen content), while there is a general decrease in textural anisotropy with maturity. We also found a reasonably good match between elastic impedance estimated from SAM images and impedance computed from ultrasonic measurements.
Date: November 1, 2004
Creator: Mavko, Gary
System: The UNT Digital Library