Wide Azimuth Seismic Attribute Extraction Method Research

In the field of petroleum exploration, the conventional porous type reservoir resources have been less and less, our country has put the exploration focus to the storage large fractured reservoirs in our country. However, fracture reservoirs of low porosity and strong heterogeneity, and the fracture distribution is complex, the conventional exploration methods effect is not very ideal, how effective exploitation of fracture reservoir has become a recognized in the field of geological exploration. This paper adopted wide azimuth seismic data that has a good effect on fracture prediction, using the characteristics of wide azimuth seismic data in all kinds of the opposite sex, wide azimuth seismic data combining with the advantages of seismic attributes can get more accurate prediction of fractured reservoirs of wide azimuth seismic attributes. The innovation of the specific work is as follows:Wide azimuth seismic data compared with traditional post-stack seismic data, has very obvious advantages: wide azimuth seismic data information is rich, the anisotropic characteristics of fault, fracture recognition effect is very good, can more elaborate the small fault and fracture performance. But, wide azimuth seismic data in different azimuth change of the time slice of subtle, directly by observing the contrast of each azimuth slices for seismic interpretation difficult. In this paper, based on the wide azimuth seismic data, using anisotropic characteristics, formed can enhance slice of subtle features in the wide azimuth seismic attribute extraction method. The innovation of the specific work is as follows:1. This paper proposed the wide azimuth coherence and the wide azimuth variance algorithm: wide azimuth seismic signals in a continuous homogeneous geological structure data travels in different directions with a regional differences will be very big, these differences reflect the formation of the discontinuous geologic structure. This paper for the first application of coherence and variance body attribute in the wide azimuth seismic data, through the calculation with a different direction of similarities and differences of data, has been able to show the formation of the fault, fracture and other wide azimuth coherence of geological structure and wide azimuth variance. Wide azimuth coherence and wide azimuth variance body relative to the original amplitude slices and post-stack coherence and post-stack variance body attribute, the fracture prediction effect is better.2. Wide azimuth texture attributes algorithm is proposed: the algorithm using the wide azimuth seismic data in different Angle signal after fault, fracture of the geological structures such as signal transmission speed and strength are different of the opposite sex characteristics, firstly we calculate different azimuth seismic attributes of three direction of the gradient to get the data body structural differences, then by the gradient data calculating correlation matrix of each point in space, according to the correlation matrix of each point to get a series of predictable formation under the fault, fracture and cavity, dissolved pore geological structures such as wide azimuth texture attributes, these attributes and the texture properties of post-stack seismic data body, compared to crack and fault prediction effect is better.3. Wide azimuth curvature attribute algorithm is proposed: the algorithm of each point in the use of space in different azimuth Angle amplitude value of the difference in the space to construct a three dimensional space curved surface, in the use of interpolation algorithm to 3-d space curved surface after completion, finally calculated the surface curvature center of curvature to get the target attribute. The curvature properties used in the actual seismic data body, the work area of the special geological structure prediction effect is good, has reached the expected goal.Finally, in the actual application of seismic data, get all kinds of wide azimuth seismic attributes with the same work area comparing the conventional post-stack seismic attributes and the effect has obvious improvement, achieved the desired effect in advance.