A rock physics model-based approach to delineate deep and tight sand reservoir heterogeneity in the Bohai Bay Basin, China
Year: 2025
Type: article
Abstract: Delineating sweet spots is critical for the exploration and production of oil and gas in deep and tight sand reservoirs. The lack of advanced and reliable methods makes this a challenge for geologists and geophysicists. This study introduces, for the first time, an integrated workflow that combines pre-stack seismic inversion with rock physics modeling to predict reservoir porosity and shale volume (V-shale) for sweet spot identification in tight sand reservoirs. A new elastic parameter, the density calculation index (DCI), is introduced which links acoustic and shear impedance for seismic density inversion, thereby addressing the long-standing problem of poor density inversion accuracy. A novel combined Sun–Walsh rock physics model, developed as part of this study, significantly improves V-shale evaluation from seismic data. The proposed three-step seismic inversion approach includes: (1) deriving acoustic and shear impedance from angle-stack seismic data using model-based inversion; (2) calculating density using shear impedance constrained by DCI, followed by porosity estimation from the density–porosity relation; and (3) evaluating V-shale using the α-parameter derived from the Sun–Walsh model and pre-stack inversion results. This integrated workflow provides an effective tool for building accurate 3D reservoir models, and is especially applicable to deep, low-porosity, tight sand reservoirs worldwide. • A new elastic parameter for seismic density inversion. • The Sun-Walsh model derived to improve the accuracy of V-shale seismic estimation. • Potential applicatoion to deep, low-porosity, tight sand reservoirs worldwide.
Source: Energy Geoscience
Authors: Donghong Zhou, Qifeng Dou, Jiaqi Jiang, Yihao Deng, Xiaodong Wei, Xingrui Dou, Yuhui Zhao, Fengyang Dong
Language: English
Subfield: Geophysics
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4415680986