Seismic AVO statistical inversion incorporating poroelasticity

Petroleum Science

Hai-Kun Lin¹  Xing-Yao Yin¹  Zhao-Yun Zong¹  Kun Li¹ 

[1] School of Geosciences, China University of Petroleum (East China), 266580, Qingdao, Shandong, China;Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, 266071, Qingdao, Shandong, China;

关键词: Poroelasticity;    AVO inversion;    Statistical inversion;    Bayesian inference;    Seismic fluid discrimination;   

DOI  :  10.1007/s12182-020-00483-5

来源: Springer

【 摘 要 】

Seismic amplitude variation with offset (AVO) inversion is an important approach for quantitative prediction of rock elasticity, lithology and fluid properties. With Biot–Gassmann’s poroelasticity, an improved statistical AVO inversion approach is proposed. To distinguish the influence of rock porosity and pore fluid modulus on AVO reflection coefficients, the AVO equation of reflection coefficients parameterized by porosity, rock-matrix moduli, density and fluid modulus is initially derived from Gassmann equation and critical porosity model. From the analysis of the influences of model parameters on the proposed AVO equation, rock porosity has the greatest influences, followed by rock-matrix moduli and density, and fluid modulus has the least influences among these model parameters. Furthermore, a statistical AVO stepwise inversion method is implemented to the simultaneous estimation of rock porosity, rock-matrix modulus, density and fluid modulus. Besides, the Laplace probability model and differential evolution, Markov chain Monte Carlo algorithm is utilized for the stochastic simulation within Bayesian framework. Models and field data examples demonstrate that the simultaneous optimizations of multiple Markov chains can achieve the efficient simulation of the posterior probability density distribution of model parameters, which is helpful for the uncertainty analysis of the inversion and sets a theoretical fundament for reservoir characterization and fluid discrimination.

【 授权许可】

CC BY