Conditions of Karst Cave Formation in Deep Strata in Maoba Syncling Mountain Region

摘要

Maoba syncline locates on the Chuanqianxiange fold zone in southwest part of China. It is a relatively unattached hydrogeology unit. Limestone of Permain and Triassic stratum is in the middle part, and a relatively impervious layer formed by siltstone and mudstane of Silurian is around it. In the ground surface karst is very development in this region. Now in the mining course of Yuanliangshan railway tunnel some large karst caves have also been found in the deep stratum. Their depths under the ground are about more than 6 hundred meters. In this paper hydrogeology condition of Maoba syncline mountain region is analyzed. On the base of analysis the forming condition of karst cave in deep stratum is studied. The research result gave more information for the geological super-leading forecast during tunnel construction.