Research On The High Precision ICP-MS Uranium Series Chronology Of Cave Stalagmites And The Paleo-climatic Changes In The South-Western Karst Region, P.R. China

The deterioration of global environment is a big challenge to scientists, therefore global changes research as an important scientific project has been researched in the all over the world. To forecast global changes and estimate it impact on survival condition of human and bring forward some advices in decreasing those deterioration, we can keep harmony and sustainable development with nature in the end. To improve ability to forecast present, we should have good knowledge of the past global changes, which is a key point in global changes research. There are many advantages to research past global changes in China, on the one hand, which have some global general climatic characteristics induced by global atmospheric physical system; on the other hand, which have some unique climatic characteristics induced by special geographical location, such as distinct monsoon climate, strong continental climate and various climatic types. Therefore, researching past global climate changes of China have very significant advances on establishing global climate changes model and forecasting local climate changes in China.Forming of cave stalagmites has close relation to atmosphere, hydrosphere, biosphere and lithosphere. There are continuous karstification occur, when atmospheric precipitation move in biosphere and lithosphere. Stalagmites very well respond to the external environmental changes during forming with karstification, as good preservation of environmental signals which can record information of reconstructive nature by human and climatic and ecological changes from hundred thousand years ago. Therefore, stalagmites are good archives of past climatic changes in continent. There is 5.4×10⁵km² karst region in the South of China, and caves well develop. As a good geological archive, stalagmite can record interaction changes of the monsoon and the intertropical convergence zone (ITCZ), which connected to the past climate changes in the South of China. We can reconstruct paleo-climatic and paleo-environmental change mode via researching stalagmites records, which can provide the scientific foundation for sustainable development between human and nature in the Karst region. Advance of researching in stalagmites keep pace with the development dating technique, and new dating technique administer to develop rapidly in reconstruction paleoclimate by stalagmites. Therefore, the precise chronology established is the first factor for reconstructing paleo-climate by stalagmites. This dissertation firstly research on high precision ICP-MS uranium series chronology methods, base on the chronology research we reconstruct paleo-climate by stalagmite Y1 records from Yamen Cave, Libo County, Guizhou Province, China. From researching of ²³⁰Th data and stable isotopes data of stalagmite Y1, the following conclusions can be made.(1) The precise chronology established has the practical significance to reconstruct paleo-climate by stalagmite; ICP-MS ²³⁰Th dating method is accurate and credible, which has...