Study of seismic physical modelling of fractured reservoirs
WANG Lingling1, WEI Jianxin1, HUANG Ping2, DI Bangrang1, QIN Shuyuan1
1 State Key Laboratory of Petroleum Resources and Prospecting, CNPC Key Laboratory of Geophysical Exploration, China University of Petroleum-Beijing, Beijing 102249, China 2 Exploration and Development Research Institute, PetroChina Southwest Oil & Gasfield Company, Chengdu 610041, China
A small fracture-scale, multi-fractured parameter proportional model of a fractured reservoir has been constructed in the laboratory based on the geological background of Longgang in the central Szechwan Basin, southeast China. Small-scale fractured zones with variable fracture parameters are constructed to simulate the equivalent characteristics of all fractures in certain regions and paper sheets are used to simulate fractures. The model is a trial of the fractured physical model technique. Then the data acquisition and processing are carried out to obtain azimuthal data. Finally, we analyse amplitude at central CDPs of four fractured zones with different fracture densities versus incident angles and the azimuthal anisotropy of amplitude and frequency attenuation gradient attributes are used to detect the development of fractures. The results show that the amplitude of the fractured zones has characteristics of azimuthal anisotropy and the fitting results of the azimuthal amplitude show the predicted orientations are around 90o and four fracture densities have an increasing trend, in accordance with the model design. The azimuthal anisotropy of frequency attenuation gradient attributes is more sensitive to small fractures, comparing with amplitude.
Key words：
fractures physical model anisotropy fracture detection
