Elastic rock properties analysis of diagenetic facies identification of deep tight sandstone in the Xihu Sag, China

Abstract

In order to investigate the physical relationship between elastic properties and reservoir parameters, and determine sensitive seismic elastic parameters of diagenetic facies of deep tight sandstone in the sparse well network area, 16 samples of typical diagenetic facies were selected for rock physics experiment. Diagenetic characteristics and diagenetic facies of tight sandstone were analyzed using petrographic data, and mineral associations and diagenetic pathways of diagenetic facies were investigated. Then, based on rock physics experiment data and petrographic data, sensitive seismic elastic parameters were determined, by comprehensively using rock physics analysis, correlation analysis, and relationship between diagenetic characteristics, mineral composition and seismic elastic parameters. Sensitive seismic elastic parameters can identify four diagenetic facies of tight sandstone. The results show that shear modulus, p-wave to s-wave velocity ratio, p-wave impedance and porosity data volume are sensitive to diagenetic facies, and the correlation between four seismic elastic parameters is weak. The determination of sensitive seismic elastic parameters in this study makes seismic diagenetic facies research targeted to distinguish four diagenetic facies. Understanding the basic physical significance of four elastic parameters is very important for their application to diagenetic facies prediction.