摘要
通过构造、岩浆、变质、成矿等地质作用及其时空演化规律的对比分析,以及物探重力、航磁及遥感信息的综合研究,认为古生代阿尔泰富蕴地幔热柱成因的三联点裂谷形成与演化———“手风琴式”开合,是阿尔泰大型- 超大型矿床富集区形成与演化的根本原因。地幔热柱热地幔物质大规模上涌和横向扩张,产生三联点裂谷系统,导致古大陆解体,形成阿尔泰“洋岛型”蛇绿岩、阿尔泰型花岗岩、花岗岩化、高温低压变质带和主要大型- 超大型矿床;地幔热柱活动停止或间息,导致三联点裂谷系统发生A 型俯冲而封闭造山,形成三叉式陆间造山带和同造山花岗岩、中高压变质带及部分矿藏。
On the basis of comprehensive studies of various sorts of information such as tectonism,magmatism,metamorphism,ore_forming processes with their evolution in space and time,and geophysics,the formation and evolution(three accordion opening_closing events) of Altay large_superlarge deposits enriched region are considered to have been caused by the inception and evolution of Paleozoic Altay mantle plume_generated triple junction rifts.Ascending and lateral spreading of the mantle plume opened the triple junction rifts,resulted in the continental break_up,and generated Altay “ocean island_type” ophiolites,Altay_type granitoids,granitization,high_temperature and low_pressure metamorphic belts and chief large_superlarge deposits in the enriched region.Subsiding or resting of the mantle plume caused the A_type subduction,closing and orogeny of the triple junction rift system,and yielded triple_type intracontinental orogenic belts,synorogenic granitoids and some mineral deposits.
基金
国家三0 五项目!阿尔泰地区成矿规律与成矿系列研究阶段成果
关键词
地幔热柱
超大型矿床
富集区
地壳演化
铜矿床
mantle plume triple junction rift continental break_up large_superlarge deposits enriched region Altay