Fluid identification based on direct inversion of equivalent fluid bulk modulus
Deng wei1, Yin Xingyao2, Zong Zhaoyun2
1. School of Geosciences, China University of Petroleum(East China), Qingdao, Shandong 266580, China;
2. Function Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266071, China
Abstract:Fluid factor is important for reservoir fluid identification,equivalent fluid bulk modulus is more sensitive to different types of fluid within the pores of rock than conventional fluid factor.Pre-stack seismic inversion can effectively get equivalent fluid bulk modulus.With porous elastic medium petrophysical model,a direct relationship between equivalent fluid bulk modulus and Gassmann fluid is established.The Zoeppritz approximate and elastic impedance equations are derived.Direct inversion is realized based on elastic impedance equation of equivalent fluid bulk modulus.Model test verifies the feasibility of the method,the actual data inversion indicates that the method improves the accuracy of fluid identification.
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