Application of the 3D Finite-Element Seismic Modeling Technique to Reservoir Characterization and Fluid Monitoring

Wei He, Roger N. Anderson, Yu-Chiung Teng, Xuefen Wang

The 3D Finite-Element seismic modeling technique has not been widely used in seismic data processing and interpretation because it is computationally expensive. However, the nature of the algorithm itself promises superior shape adaptation and fluid property assignment to realistic reservoirs. We have accurately mapped and characterized the Pleistocene production reservoirs in the Eugene Island Block 330 Field by using various wireline logs and core samples. The extrapolation of these observations away from wells is implemented by using inverted 3D seismic data. The sedimentary frameworks in our area of interest indicate that the primary sedimentary facies of shallow reservoirs is deltaic, and that of the deep reservoirs are graded basin floor facies. The high to moderate horizontal permeability of these reservoirs, modified by a deep-rooted large growth fault system has evidently caused the reservoir to over produce in the GA sands. By using our 3D Finite-Element seismic modeling technique with results derived from reservoir characterization, we have investigated the seismic responses of reservoir drainage by production and infilling from major growth faults in the El 330 Field area. In conclusion, we have found that 3D seismic amplitude is an effective indicator of the fluid migration when reservoir thickness is grater than tuning thickness and reservoir permeability is high. The 3D Finite-Element forward modeling technique is a powerful tool in reservoir characterization and fluid migration monitoring.

AAPG Search and Discovery Article #91020©1995 AAPG Annual Convention, Houston, Texas, May 5-8, 1995