腾冲—梁河地区砂锡矿形成条件及富集规律研究  

ON FORMATION CONDITIONS AND ENRICHMENT LAWS OF THE TIN PLACER IN TENGCHONG-LIANGHE REGION

作　　者：陈华慧[1] 何科昭[1] 何浩生[1] 赵其强[1] 

机构地区：[1]中国地质大学

出　　处：《云南地质》1991年第4期337-361,共25页Yunnan Geology

摘　　要：在充分研究区域的地貌、第四纪地层及新构造的基础上,分析了腾冲-梁河地区砂锡矿的形成条件和富集规律。本区形成砂锡矿的有利条件为:砂锡矿的物质来源——含锡母岩;有利于砂锡矿堆积的控盆构造;有利于含矿母岩不断破坏的控风化剥蚀构造;配套的剥蚀地貌、侵蚀地貌和堆积地貌;有利于含矿母岩风化的湿热气候;有利于砂锡矿富集的水流动力条件。砂锡矿的富集规律为:云英岩发育的地区很可能富集砂锡矿;靠近原生锡矿的活动断裂带附近有利于富集砂锡矿;风化壳砂锡矿底部及粘土细粒层的表层,砂锡品位相对较高;坡积砂锡矿在接近含矿母岩处品位最高;冲积砂锡矿在区内最为发育,在接近含矿母岩处品位最高。以山寨盆地为代表,洪积及冲-洪积砂锡矿在盆地西缘极其发育,湖滨砂锡在近岸粗碎屑物中较为富集。Based on the studies of the regional landforms, Quaternary strata and neotectonics, we analyse the formation conditions and enrichment laws of the tin placer in Tengchong-Lianghe region. Conditions which are favourable to the formation of the tin placer in this region are: the mother rock of the tin placer; controlling structures which are favourable to the accumulation of the tin placer in the basin and to the repeated fracture, weathering and denudation of the ore-bearing mother rock; a suit of landforms of denudation, erosion and accumulation; the damp and hot climate which is favourable to the weathering of the ore-bearing mother rock; stream dynamic power which is favourable to the enrichment of the tin placer. The enrichment laws of the tin placer are: areas well developed with greisen are quite possible to have enriched tin placer; the active fault zone which is close to the primary tin deposit is favourable to the enrichment of the tin placer; relatively higher tin grades are found in the bottom of weathering crust and in the surface layer of the fine clay beds; the highest grade of the deluvial tin placer lies in the part adjacent to the ore-bearing mother rock; the alluvial tin placer developed best in this region with its grade being hig-best in the part adjacent to the ore-bearing mother rock; the proluvial and alluvial-proluvial tin placer was developed very well along the western margin of the basins, which are represented by Shanzhai basin, and the lacustrine tin placer got more enriched in the coarse fragments adjacent to the bank.

关 键 词：砂矿 锡矿 成因 富集 腾冲-梁河 

分 类 号：P618.44[天文地球—矿床学]