Distribution-controlling factors and emplacement mode of lamproite in southeastern Guizhou Province

A large number of lamproite plutons were discovered in eastern Guizhou Provence, which are distributed either as regional elliptical pattern and/or local banding pattern. Dating information reveals that they were mainly formed in late Ordovician. Geohisto-ry analyses suggest that geological structural conditions of the substrate of the lamproite pluton regions should resemble those of the rhombic structural framework that characterized the "Jiangnan old land", after experiencing multiphase tectonic movements including Wuling Orogeny, Xuefeng Orogeny, and Yunan Orogeny as well as Duyun Movement in the Caledonian. The resulting geological structural condition thus accounted for the formation of the lamproite plutons, i.e., elliptical pattern in regional and banding pattern locally. In combination of dating data and lithofacies paleogeography studies, the authors hold that lamproite plutons were emplaced at the position with the mode of "loach throw bean-curd", which was controlled by substrate structural conditions. The prospecting and exploration policy should primarily focus on "exploring to the deep and unknown places" of existing deposits.