Multi-wave Seismic Technology Apply In The Crack Description Of Wang Jia Tun Igneous Rock

Wang jiatun gas reservoirs is igneous rock, where the geological conditions are very complicated and the reservoir property change greatly. Because of the different types of igneous rocks, the rock structure is very different, and the reservoir capacity is greatly related to the formation of the tectonic stress. The development and distribution of fractures are the main controlling factors of gas reservoir and migration, and the distribution of fractures is often multi-scale and inhomogeneous.Therefore, how to realize the prediction of the fracture of igneous rock has important significance to the identification and engraving of the reservoir, and it is helpful to the development of oil and gas.In this paper, we introduced the core processing technology of converted wave and the method of conversion wave static correction. Wang jiatun igneous reservoir are described mainly through two aspects. Firstly, interpret the large sets fault area using seismic profile. On the basis of combining Wang jiatun fractured gas reservoir,the means of identification of fractured formation is introduced, focuses on the formation of cracks in the shear wave splitting detection method. Combining Wang jiatun volcanic rock fracture reservoir, perform the fracture development prediction through converted wave data from shallow to deep layer. By Alford transformation to obtain the fracture azimuth angle, and the time difference of fast and slow waves to indicate the development degree of fractures. Through the layer by layer shear wave splitting analysis, eliminating the shallow stratum fracture development of deep strata fracture prediction effect, so as to realize the deep volcanic reservoir layer crack development of fine interpretation. Finally, combined with the Poisson’s ratio,velocity ratio of seismic attribute parameters in the study area perform the prediction of oil and gas bearing.Through the above research work, the igneous rock fractured gas reservoir in the area has achieved the following results and understanding:1、 The jurassic volcano rock along the basement fault distribution, and the acid volcanic rocks of andesite has better reservoir physical condition. In the reservoir,factures are developed widely.2、Anisotropy analysis shows that there are four high value anomalies in the transverse direction, which are two bands. But the anisotropy in different directions,approximately perpendicular to each other; area of cracks is four obvious anomaly area, which the development direction of fracture general between North West 40 to60 degrees, and some individual high angle fractures;3 、 There are two high speed anomalies in the target layer, but there are differences in the velocities of the two kinds of converted shear waves. Often body velocity anisotropy direction; the speed of the two lines than in the target are high value anomaly and display for decreasing or pore cementation, compaction degree,sewing hole relative development; two lines of Poisson’s ratio in the presence of target low value anomaly, on behalf of the oil and gas; due to the Poisson’s ratio is very small, the possibility of the existence of gas greater.