Evaluation Of Regional Crustal Stability Of The New Base Of Panzhihua Iron The Xichang Vanadium And Titanium Steel

The researching area is confining by Anning river fracture and Zemu river fracture, and the Anning river area is a seismicity belt which inheritanced and developed the features of Panxigu rift valley of Hercynian-Indosinian. This area has a complex tectonic framework, the new building block had obvious differences in fracture which shows the strongly down-faulted zone, increased ground temperature zone and seismic activity zone. Therefore, this area has diverse structure and many earthquakes. The stability evaluation of area is based on geological conditions and activity history and then we summarize the factors and levels of stability. So it can reflect the status and develop trend of geological disasters correctly and forecast the harmful levels for human and property exactly. Indeed, the stability and geological evaluation for areas are important and significant for constructions.This thesis is based on researches about evolution history and the new tectonic movement characteristics of Panxigu rift valley. By combined the specific examples and the fuzzy assessment method of surrounding rock stability, we established a stability evaluation system of new base area and defined the relationship of subordination between each factor and evaluation results. The paper is include:We summrized the geological features, new tectonic movement characteristics and distribution of main geological disasters of Panxigu rift valley area. And then we collected the geological and geophysical data of this area to abstract the basic data of stability evaluation.We summrized the application of fuzzy mathematics by predecessors on area stability evaluation; according to the geological environment of Panxi area, we choose the stability factors and assign the weight, then we can have evaluation indicators and index.By taking advantage of MapGIS system, we divide it into three Modules which are Data Management, Stability Evaluation and Statistics. According to geological conditions and exploration material, we marks on each stability factors and then decides the Function to fuzzy set.Based on basic equation of membership function, stability evaluation, calculation of stability levels and the MapGIS system, we have tested and verified the example of Panzhihua New Steel Vanadium Titanium Base Project. We have conclusion that the stability of new base is not very good, the sum of unstability area and most unstability area is 63%, By calculation of membership function, it shows that the most important factor is the earthquake effect and then fracture activities.Besides, in the process of using MapGIS system, we also had some problems that the contrast of each factors and quantitative research, the conditions and results of Grid cells reflection are a bit idealized. This needs more research in the future.