重庆秀山小茶园地区南华纪大塘坡组沉积环境与锰矿产出规律

在系统分析重庆秀山小茶园锰矿区大批钻孔数据资料的基础上，基于野外地质调查和室内沉积学、地球化学等分析得出，盆地中心相的沉积物厚度大，TOC、U、Mo、V、δ34S_py的含量高，草莓状黄铁矿丰富，指示了缺氧的水体条件，且锰矿的品位和厚度大。向盆地边缘相、斜坡相，沉积物厚度减小，TOC、U、Mo、V、δ34S_py含量降低，指示水体缺氧程度减弱，同时锰矿的品位和厚度减小。锰矿体厚度的变化与含锰岩系厚度的变化规律一致，二者呈正相关关系。小茶园矿区矿体展布方向与小茶园次级地堑盆地长轴方向基本一致，为NE60°左右。因此，小茶园矿区锰矿床矿体产出受到次级地堑盆地和沉积相带的控制，缺氧的盆地中心相成矿最佳，其次为盆地边缘相，斜坡相成矿较差。

Sedimentary Environment and Manganese Ore Deposits in the Nanhua Period Datangpo Formation in Xiaochayuan Area,Xiushan, Chongqing

Based on the systematic analysis of a large number of borehole data in the Xiaochayuan manganese mining area in Xiushan， Chongqing， field geological surveys， laboratory sedimentology， and geochemical analysis have shown that the sediment thickness of the central facies of the basin is large， with TOC， U， Mo， V， δ34S_py is high， and the content of framboidal pyrite is high， indicating anoxic water conditions， and the grade and thickness of manganese ore are large. Toward the basin edge and slope facies， the thickness of the sediments decreases， and the content of TOC， U， Mo， V， and δ34S_py decreases， indicating that the degree of hypoxia in the water body is weakened， and the grade and thickness of manganese ore decrease. The change of manganese ore body thickness is consistent with that of manganese-bearing rock series， and they have a positive correlation. The distribution direction of the ore bodies in the Xiaochayuan mining area is basically the same as the long axis direction of the Xiaochayuan secondary graben basin， which is about 60° northeast. Therefore， the output of manganese deposits in Xiaochayuan mining area is controlled by secondary graben basins and sedimentary facies belts. The hypoxic basin central facies is the best mineralization， followed by the basin edge facies， and the slope facies mineralization is poor.