A mud shale seismic rock physics model considering complex pore structure

Key words:  continental shale  rock physics model  complex pore structure  rock physics cross plot template  seismic "sweet spot"

Abstract:

Based on the petrological and microtexture characters of continental shales of Qingshankou Formation in Gulong Sag, northern Songliao Basin, a combined modeling technique, including Kuster & Toksz, self consistent, double-porosity and linear slippage modeling, is used to propose a complex pore structure rock physics model for the organic-rich shale. Based on the modeling results, the influence factors, the organic volume fraction, the fracture porosity, the matrix porosity, the pore aspect ratio and the pore connectivity coefficient on the rock elastic properties are discussed. In addition, the sensitive parameters, which are sensitive to the change of organic content and total porosity, are optimized, and a rock physics crossing template for continental shales is established. Actual data have shown that the proposed model has good predictability, which can be used in the reservoir evaluation and seismic "sweet spot" for continental shale reservoir of Qingshankou Formation in Gulong Sag.