Study On Lithology Interpretation Technology Of High-density 3D Seismic Data In Huaibei Mining Area

Huaibei mining area works towards deep region with complex structure conditions, while it is difficult to obtain information about precise structure, satus of coal, lothilogy of coal’s roof and floor for conventional geological and seismic exploration technologies, severely restricting the sustainable development of coal industry of Huaibei mining area.In order to solve the problems of fine structure and lithology that endanger coal production seriously, in this study, high-density 3D seismic data of No.106 mining area, Liudian was processed to make good use of multiple lithology technologies such as seismic attributes, spectral decomposition, seismic facies analysis, seismic inversion and anisotropy technology for interpreting complex structure and lithology, a good result was obtained.Given conventional 3D seismic interpretation methods commonly baae on that of 2D seismic exploration, which always applies seimic profile to interpret structure anomaly. To this end, a fault model is established, seismic numerial simulation is carried on and multiple seismic attributes are extracted from theoretical profile. The characteristics of seismic attributes are analyzed and summarized to build a foundation for full three-dimensional interpretation. In the process of actual seismic data interpretation, firstly, slices of seismic attributes of target layers are extracted, and then structure anomaly is determined by the characteristics of seismic attributes, finally, fine structure is jointly interpreted by seismic attribute slices and seismic profiles.For the problem of magmatic rock intrusion, differences of coal, magmatic rocks(natural coke) and coal’s roof and floor in physical property are analyzed comparatively firstly, after that the range of magmatic rock intrusion is delineated respectively by multi-parameter lithological seismic inversion method based on impedance and electrical property, spectral decomposition based on differert spectrum, seismic facies analysis based on waveform difference. The range of magmatic rock intrusion is finally identified by the interpretations of these three methods, mainly by multi-parameter lithological seismic inversion method, associated by spectral decomposition and seismic facies analysis, combined with geological drill data.For the problem of gas-rich in coal, four kinds of seismic attributes are extracted from different azimuth data. The direction and density of fracture in coal is calculated by these seismic attributes, the feature of fracture is consistant with that of research region’s structure. Then wave impedance data is obtained by seismic data of different angle(offset), based on coal structure factor P value, tectonic coal zone is delineated. Finally, gas-rich anomaly is evaluated comprehensively by coal fracture density and tectonic coal zone.With respect to the interpretation of the convetional 3D seismic exploration, high-density 3D seismic method interprets fine structure more accurately, especially small faults, the compliance rate of seismic outcomes are improved obviously. The range of magmatic rocks(natural coke) and gas-rich anormaly zone is determined by multiple kinds of lithological information, with higher resolution and reliability than that of traditional geological methods.