Reservoir prediction using pre-stack inverted elastic parameters
Chen Shuang-Quan1,2, Wang Shang-Xu1,2, Zhang Yong-Gang3, and Ji Min4
1. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249 China.
2. CNPC Key Laboratory of Geophysical Prospecting, China University of Petroleum, Beijing 102249 China.
3. Science and Technology Institute, China Petroleum & Chemical Corporation, Beijing 100086 China.
4. Overseas Research Center, Petroleum Research Institute of Exploration & Development, SINOPEC, Beijing 100086 China.
Abstract：
This is a case study of the application of pre-stack inverted elastic parameters to tight-sand reservoir prediction. With the development of oil and gas exploration, pre-stack data and inversion results are increasingly used for production objectives. The pre-stack seismic property studies include not only amplitude verse offset (AVO) but also the characteristics of other elastic property changes. In this paper, we analyze the elastic property parameters characteristics of gas- and wet-sands using data from four gas-sand core types. We found that some special elastic property parameters or combinations can be used to identify gas sands from water saturated sand. Thus, we can do reservoir interpretation and description using different elastic property data from the pre-stack seismic inversion processing. The pre-stack inversion method is based on the simplified Aki-Richard linear equation. The initial model can be generated from well log data and seismic and geologic interpreted horizons in the study area. The input seismic data is angle gathers generated from the common reflection gathers used in pre-stack time or depth migration. The inversion results are elastic property parameters or their combinations. We use a field data example to examine which elastic property parameters or combinations of parameters can most easily discriminate gas sands from background geology and which are most sensitive to pore-fluid content. Comparing the inversion results to well data, we found that it is useful to predict gas reservoirs using λ, λρ, λ/µ, and K/µ properties, which indicate the gas characteristics in the study reservoir.
CHEN Shuang-Quan,WANG Shang-Xu,ZHANG Yong-Gang et al. Reservoir prediction using pre-stack inverted elastic parameters[J]. APPLIED GEOPHYSICS, 2009, 6(4): 375-384.
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2009, Vol. 6 
