| It is very important for activity analysis of the fracture, seismic hazard analysis,seismic safety evaluation of major constructions, and earthquake disaster evaluationto have the segmentation research of active faults. The faults have complex andself-organizing nonlinear systems in the earth crust. And the fault distributionappears a series of linear or planar aggregation. Fractal theory can bequantificationally measure the complexity level of the geometric construction indifferent segmentations, and associates fracture tectonic activity and seismic activity.Consequently, it can quantificationally evaluate the tectonic activity of the differentfaults or the different segmentations in the same fault.This area has complicated geological structure, a large number of historicalearthquakes, and had occurred several times5-magnitude earthquakes. There arehistorical earthquake records in Ankang-Fangxian fault zone, Baihe-Gucheng faultzone, Zhuxing fault zone and so on. So, it is worth further research.Zhushan fault and Zhuxi fault are the two typical faults. They are studied form thefractal theory perspective in this thesis. The main studies and contributions aredescribed as following:1Researched the seismic and geologic features in Zhushan fault zone and Zhuxifault zoneIn base of existing seismic and geologic data, we deeply investigated the tectonicgeologic feature, topography and geomorphology, quaternary geology and historicalearthquake in the region. And drew the integral fault profile of Zhushan fault zoneand Zhuxi fault zone and Zhushan fault zone geological map (1:100000).2Used the fractal theory to put on fracture active segmentation of Zhushanfault zone and Zhuxi fault zoneAfter summarized these seismic and geologic features, tectonic stress environmentand referencing geological segment features, set a fracture fractal segment model.Use the fractal theory to put on study of fracture active segmentation. 3Studied the multi-fractal characteristics of Zhushan fault zone and Zhuxifault zoneSet a multi-fractal model of Zhushan fault zone and Zhuxi fault zone, and gaintheir multi-fractals spectrum, and quantify their active differences. The results ofmuti-fractal model are as following:①Horizontal comparison, Zhuping-Tianjiabasegment is stronger than Zhushan-Fangxian segment in energy clustering and theinhomogeneity and nonlinear of the fracture distribution.②Vertical comparison,Zhuxi fault zone’s multi-fractal spectrum interval is different from Zhushan faultzone’s. Thus, illustrate that they are belong to two different tectonic system. Because,Zhuxi fault zone has a lower spectrum. So, it has a more stronger inhomogeneity,nonlinear and activity.4Researched the multi-fractal characteristics of Zhushan fault zone and Zhuxifault zone related seismic activityThe earthquakes are related to the fracture, and complementary exist. In order todeeply research the fracture activity, set a25km buffer analysis model and study themulti-fractal characteristics of the related seismic activity. Gain the multi-fractalspectrums of the earthquake (1.0ML4.0) and (ML4.0). The results indicatethat they have different seismic activity, and the former activity is stronger than thelatter when earthquakes take place. |
