广西锡多金属大地构造成矿演化、分带与找矿方向

Geotectonic Metallogenic Evolution and Belt of Tin Polymetal Ore and Exploration in Guangxi

广西锡多金属成矿系统是一个不同时代成矿体系的亲缘性谱系。富含Sn等成矿元素的变质基底和古老岩浆岩组成的地球化学块体是成矿的物质基础,大地构造活动是成岩成矿的动力来源,Sn等成矿元素以不同的形式多阶段聚集成矿,表现出螺旋式不均衡的发展性和继承性,在燕山期和藏南期达到成矿高峰。广西可分为四堡—雪峰期桂北、燕山期桂东北-桂东南和藏南期桂西北-桂西南3大锡多金属成矿带。锡多金属战略找矿的重点是桂西地区,该区具有上金下锡的"双层成矿"模式。寻找"大厂式"超大型矿床的方向应放在桂西藏南期3个锡多金属成矿亚带上,其中重点是桂西南锡多金属成矿亚带。

Metallogenic system of tin polymetal in Guangxi is a pedigree composed of ore-forming series in different era. The geochemical block with metallogenic material base is composed of metamorphic basement and old magmatic rock rich in ore-forming elements of Sn etc.. Geotectonic movement results in the formation of rock and ore, displaying spiral unbalanced development. The ore-forming elements of Sn etc. gathered and formed into ore through different way in different era. Metallization reached a high tide in the Yanshan stage and the Zangnan stage. In Guangxi, three tin polymetal metallogenic belts can be divided as following： the northern Guangxi tin polymetal belt in Sibao-Xuefeng stage, the northeast -southeast tin polymetal belt in Yanshan stage and northwest-southwest tin polymetal belt in Zangnan stage. West Guangxi is priority in strategic prospeering of tin polymetallic ore. In the tin-polymetals district in Guangxi, there is a ＂Bilayers Mineralization Model＂, indicating that the gold mineralization overlies the tin-polymetallic mineralization. The exploration strategy for the ＂Dachang-Type＂ superlarge deposits should be focused on the three subbelts of tin-polymetals metallization which were formed during the Zangnan stage in west Guangxi, especially on the subbeh of the tinpolymetal metallization in southwest Guangxi among the belts.