Dating The Development Of Collapse Pillars In Coal Measure In Taiyuan Xishan

Collapse pillar was only found in China, especially in Northern China. It had great effect on coal mining, and causes substantial economic expense. So research in collapse pillar was absolutely necessary both in engineering and science.The time collapse pillar developed was one important part of this research. On the one hand, this time will be helpful for determining underground karst evolution and spatial distribution. On the other hand, it could provide a theory basis for predicting the distribution of collapse pillars and optimizing coal mining face layout and mining technology. However, there were no dating study before.In this research, the author tried to constraint the development time of collapse pillars in Taiyuan Xishan by geochronological methods, such as U-series. Firstly, the author constraints rough time span in field investigation and geological analysis(including large-scale tectonism, regional basin-range evolvement and karst hydrological system), and traced the geochronological recorder which involving basin sediments, valley terrace remains and cave deposits, then choose appropriate dating means-14C, U-series, thermoluminescence, optically stimulated luminescence, electron spin resonance and fissiontrack according to time-range of different dating methods and the available samples. Secondly, the author comprehensively considered sampling feasibility, veracity and precision in result, and also test cost and time, then carried out field sampling, dating in the laboratory, at the same time analyzed errors in entire test process one by one, and thought over data reliability. Finally, the author determines geologic events-time series, including karst collapse pillar development in Xishan Coalfield, Taiyuan.