Study On The Formation And Protection Of The Karst Caves In Yangchun National Geopark, Guangdong

Yangchun city lies in the middle section of the Sihui—Wuchuan deep faultbelt.Since the Neoproterozoic , the Sihui—Wuchuan deep fault belt has controled thetectonic evolution of the Yunkai plot in the east and the Huaxia plot in the west, it was animportant borderline between Yunkai plot and Huaxia plot.Therefore,Yangchun had beeninfluenced deeply by the fault belt.This dissertation deals with the forming process of the karst caves by the methods oftectonics, stratigraphy, Quaternary physiognomy and karst geology. In theCarboniferous,Yangchun area was covered with shallow sea,where the calcium carbonatesdeposited,then the thick –beded limestone and dolomite limestone formed. After theIndosinian movement,Yanshanian movement and Sichuan movement,the lithosphere ofYangchun area became the land,and the multi-oriented joints are formed in limestone. Inthe early middle pleistocene,the karst caves in Yangchun area began to develop. With therising of the lithosphere and the downcutting of the river,the karst caves in Yangchun areaformed multilayer configuration. The strikes of the caves are almost along the NNEdirection because of the influence of Sihui—Wuchuan deep fault belt. The earthquakeshappened in this area is the reason of the big rock block accumulations in the caves.Karst caves are very invaluable,and they are non-renewable, so we must protectthem immeidiately. Except for the protections by policy and system,we must improve theprotective methods by using advanced technology. The protection of water system andsediments in the caves is very important.Based on the previous protective methods of thekarst caves, I propose two new protective methods according to the conditions of thekarst caves in Yangchun area. They are all the methods for protecting the sediments in thecaves. The two methods are controling of the lights in the caves and using the nanometertechnology to repair the sediments.To sum up,the formation of karst caves in Yangchun area is related to the geotectoniclocation,tectonic envolution, climate and so on. The invaluable karst cave in Yangchunarea must be protected at once. Except for the protection by policy and system,we mustadopt the high technological protection methods.we should adhere the principle ofprotection the first,development the second,and persist the sustainable development allthe time.