The Research Of Seismic Identification Technique Of Heterogeneous And Fracture Tight Gas Reservoir Of Xujiahe Formation, In Chuanxi Depression

This dissertation pays a main research on the tight clasolite gas pool of upper Triassic Xujiahe Formation on the middle segment in west Sichuan depression. On the basis of the whole analysis of basic character of deep-buried Xujiahe Formation reservoir and gas accumulation rule, this paper integrates seismic data acquisition, processing and interpretation, and aim at those problems such as deep-buried Xujiahe formation reservoir prediction, fracture detection and gas-bearing sand identification. By means of studying relevant seismic attribution scrutinizingly, author developed a suit of problem-orienting and innovated methods which are very suitable to identify Xujiahe Formation reservoir in West Sichuan depression.The idea of processing seismic pre-stack data is characterized with "Keeping credible and relevant amplitude changes". According to the need of predicting deeply seated Xujiahe Formation gas pool, a set of key seismic data processing technique has been developed. Those key technologies include pre-stack automatic denoise method in the multi-field which keeps relevant amplitude, tomography static correction method using nonlinear first arrival wave, non-hyperbola moveout dynamic correction method, and etc. The matching techniques have also been founded. The prestack automatic de-noising technique in the multi-field is developed by our own and very successful to remove noises of seismic data in the Chuanxi region.By analyzing log and seismic response of different reservoirs in Xujiahe Formation, integrating the high-resolution sequence strata and seismic strata, the author developed the reservoir prediction methods of Xujiahe Formation and summarized the prediction mode of reservoir which features "bright spot" and is based on wave form.It is the first time designing a three-D width survey system of seismic data acquisition and putting it into action, which has a pattern of brick wall and has good azimuth character. By calculating the directional characteristic of P-wave, the software to predict anisotropism of layer and the density and azimuth of fracture is developed independently, which has integrated 3-D data acquisition of broad azimuth, pre-processing of prestack data and prediction of fracture. The technique and method using P-wave feature to detect pony-size fracture are most reliable and straightforward presently .In order to detect the fracture of Xujiahe Formation reservoir, we developed a set of seismic.