贵州镇宁-紫云泥盆系重晶石矿床中热水成因灰岩的发现及其地质意义

Lenticular and nodular limestones occur in the Zhenning-ziyun barite deposits in the Devonian. Research on rock structures related to the limestones found that the structure is compact, grain size is small and thickness horizontally changeable. This paper separately makes carbon and oxygen isotope determination on limestones samples in the barite belt of Devonian System from Xiyahe Profile and Luocheng Profile in Zhenning-Ziyun County. the result demonstrates the δ13C values of the limestone in Xiyahe Profile and Luocheng Profile are individually within -8.82‰~-10.27‰ and +0.03‰~-3.31‰, and the δ18O values are individually within -8.10‰~-8.20‰ and -7.43‰~-7.91‰. Its strong negative carbon isotope anomaly and occurrence characteristics are similar to the hydrothermal sedimentary genesis of coarse-grained limestones in the Ni-Mo deposits in the Basal Cambrian. As a result, we believed that the interbedded limestones located in the Zhenning-ziyun barite deposits in Devonian formed by hrdrothermal exhalative mineraization which provides new evidences for hydrothermal sedimentary genesis of barite deposits.