Application of Seismic Multi-Wave Amplitude Attributes to Dolomite Prediction

A number of dolomite reservoirs in the Permian Qixia Formation in the central Sichuan Basin have been drilled and obtained high production, indicating that they have high exploration potential. High and medium porosity dolomite reservoirs are the main gas-producing reservoirs in the Qixia Formation. However, the P-wave velocity is unable to distinguish between medium-porosity dolomite and limestone, which leads to P-wave seismic data only being used to predict high-porosity dolomite reservoirs. Multi-component seismic exploration is a potential solution to solve the problem of fine prediction of medium porosity reservoirs. It is found that medium porosity dolomite and limestone have obvious differences in S-wave velocity. And through the comprehensive analysis of elastic wave forward modeling, it is believed that PS-wave data have a better identification effect on medium porosity dolomite reservoirs. The comprehensive use of PP-PS wave amplitude attributes and paleo-geomorphology, can effectively predict high porosity and medium porosity dolomite. The prediction results are highly consistent with geological understanding and drilling conditions, which support the exploration and development deployment of the Qixia Formation in this area.