摘要
密西西比河谷型(MVT)铅锌矿是世界最重要的铅锌矿床类型之一,MVT矿带或其附近往往相伴有砂岩型铜矿、铀矿、铁矿(化)等。对新疆塔西南地区主要容矿地层建造、主要类型矿床典型矿床解剖等方面的研究发现,这些矿床的形成均与盆地卤水作用有密切的关系。这些矿床的含矿建造往往为一些特定的沉积岩石组合,诸如碳酸盐岩(上)/紫色砂岩(下)组合、膏盐层(上)/紫色砂岩(下)组合、紫色泥岩(上)/砂(砾)岩(中)/紫色泥岩(下)组合等,分别控制MVT型铅锌矿和铁矿、砂岩型铅锌矿、砂岩铜矿和铀矿等。塔西南地区的MVT、砂岩型铅锌矿、铜矿、铀矿等均分布于红层盆地和生烃岩盆地附近。其中,红层盆地形成于中新世,提供氧化性的卤水,在渗透性良好的砂岩中迁移时,淋滤其中的金属物质,因此富含Pb、Zn等元素;生烃岩盆地主要是侏罗纪盆地,提供富含有机质的还原性卤水,其中可能富含低价态的硫。不同类型矿床成矿机制不尽相同,但主要与两类盆地卤水作用有关。
The Mississippi valley type Pb -Zn deposit （MVT） is one of the most important lead -zinc resources. The sandstone type copper, uranium, iron ore deposit or mineralization usually occurred in the MVT belt. On the studies of the geology and geochem- istry of the typical deposits and the ore- hosting strata in the southwestern Tarim basin, Xinjing, it suggests that there is a close rela- tionship of the ore - forming process among the different types of deposit, and that all of the deposit types are associated with the basin brines. Ore formation of these deposits are often some particular sedimentary rock assemblages including carbonate rocks （up） / purple sandstone （down） assemblage, gypsum （up） / purple sandstone （down） assemblage, and purple mudstone （up） / sand （middle） rock / purple shale （down） assemblagewhich control the distribution of the MVT lead zinc ore and iron mineralization, sandstone type lead - zinc deposit, and sandstone type copper and uranium deposits respectively. The key factors of metallogenic geology of the depos- its includ the red bed basin and hydrocarbon source rocks （basin）. The MVT, sandstone type lead -zinc, copper and uranium depos- its occurred in the vicinity of these two types of basin in the southwestern Tarim basin. The oxide brines from the Miocene red bed basin flowing in permeable sandstone, leach Pb, Zn and other metal elements. Jurassic basins are mainly the hydrocarbon source, and the reducible brines from the basins rich in organic matter, which may contain low reduced sulfur. The mineralization mechanism of differ- ent types deposit are not the same, but mainly associated with those two kinds of brines react each other in special sedimentary rock as- semblages.
出处
《矿产勘查》
2014年第2期136-148,共13页
Mineral Exploration
基金
国家973计划项目(编号:2014CB440803)
有色金属矿产地质调查中心科研项目(编号:2004ZHXM002)联合资助
关键词
铅锌矿
铜矿
铀矿
密西西比河谷型
砂岩型
盆地卤水
红层盆地
成矿系统
lead -zinc deposit
copper deposit
uranium deposit
MVT
sandstone -type deposit
basin brines
red -bed ba-sin
metallogenic system
作者简介
祝新友,男,1965年生,硕士,教授级高工,从事矿床学研究工作.
