Research On The Intrinsic Structure Feature And Characterization Means Of Fault Zone

As the products of faulting, faulted zones record abundant information of faulting, and the intrinsic structure of them decide their macroscopic distinctions. The research on their intrinsic structure and fluid migration can help to fulfill human’s needs in fields like geographical engineering, resources and environment, such as high radioactive waste disposal, geothermal exploitation,CO2 disposal, water engineering construction, cause of fluid and mineral prospecting. In addition, permeability of faults is of significance to the research on faults mobility, especially seismology. What’s more, the permeability of faults is the most important parameter to understand the state of the stability and deep-seated fluid.Based on the Shiyuejing faulted zone in Beishan Gansu, the paper carries out meticulous study on its intrinsic structure and its permeability. The major contents and contributions are as follows:(1) Detailed site investigation and sampling was carried out on the core, crushed zones and induced fracture zone of Shiyuejing fault. A summary which sums up previous research methods and results on the basis of many a literature on faults intrinsic structure, was used to guide the research.(2)Researches were conducted on the intrinsic structure of the Well, such as the size characteristic, mineralogy, and microstructure. Substances in faulted zones are characterized by zonality, i.e., faults in different places are apparently different in intrinsic structure.(3) Mercury-injection experiment was carried out to study the gap texture of gouge in epiderm of Shiyuejing fault. It is found that most of the gaps in gouge are intergranular opening, resulting in the aeolotropism in the gouge.(4) Experimental equipment and methods are upgraded to carry out indoor permeability test, thus obtaining the meinzer of gouge. Combining this with its size characteristic, mineralogy and microstructure, we also discussed the intrinsic mechanism of the permeability characteristics.(5) Characterization means study was carried out, using NMR and CT, to study flaw texture of fault rock mass. The selection of parameters and experimental methods of NMR on granite were upgraded. CT scanning was done to obtain the image of intrinsic flaw, and MATLAB was use to draw parameter of rock flaw structure.