The special of siliceous rocks is distributed at the bottom of Permian manganese ore deposits in Zunyi, Guizhou Province. The set of siliceous rocks surrounding the manganese enrichment region produced, known as the“Bainitangceng”or the“wall form”siliceous rocks. The genesis of siliceous rocks is considered associated with manganic metallogenesis. According to careful investigation in the field, it was found that the set of siliceous rocks’structures are ribbon, breccia and block, the steel grey and black manganese stringer is across the ribbon cherts. The spatial distribution of brecciated structure siliceous rock is astatism, the more closed to the manganese ore, the more densely the brecciated structure siliceous. Element geochemical analysis of 10 siliceous rock samples show that siliceous rocks have high SiO2（80.55% ～99.56%）and Fe2O3（0.47% ～13.76%）, lower Al2O3（0.05% ～4.06%）and TiO2（0～0.49%）, which indicates that terrigenous detrital material rarely participate in the process of siliceous rocks formed. The ratio of（La/Ce）N and the Ce anomaly value characteristics indicate that siliceous rocks was formed in the deep-water reduction environment at fracture basin. The diagram of Fe-Mn-Al and SiO2-Al2O3 indicate siliceous rocks mainly fall into the hydrothermal sedimentary zone or near the area. Al/（Al+Fe+Mn）,（La/Ce）N , Y/Ho and Eu/Eu* ratios are 0.26, 1.51～2.34, 30.64～43.91, 0.96～1.67, and standardized REE distribution pattern is similar to hydrothermal sedimentary siliceous rocks, which illustrates that siliceous rocks have obvious hydrothermal matter participation in the process of diagenesis. The genesis of the siliceous rocks is belong to hydrothermal sedimentary genesis. This conclusion provides new evidence for the hydrothermal sedimentary origin in Zunyi Permian manganese deposit.
Xu Hai Gao Junbo Yang Ruidong Zheng Lulin Zhang Xu. The origin of siliceous rocks in Zunyi Permian manganese ore fields in Guizhou Province and their metallogenic significance[J]. Chinese Journal of Geology, 2017, 52(4): 1297-1311.