大陆边缘成矿

METALLOGENY OF CONTINENTAL MARGIN

大陆陆壳的形成与发展经历了陆核—地块 (台 )—联合大陆—大陆裂解—陆缘增生—碰撞造山的演化过程。地壳通过不均一性分异而形成大陆型和大洋型地壳,大陆裂解、洋壳向陆缘消减和陆 -陆碰撞拼接则形成具有不同构造特征的大陆边缘。以中国大陆已存在的 3条陆壳对接消减带为界划分了 5个大陆边缘构造带,进一步区分出 13个次一级的边缘构造区及其内的 53个时空配置结构,并据现有矿产地计算了边缘构造区的矿产发现几率。将中国大陆边缘划分为离散型、会聚型、对接型和转换型 4类,总结了其成矿系列类型专属;认为大陆边缘普遍性成矿有利因素的耦合对成矿至关重要,而最佳耦合的机制及其发生在大陆边缘区的时空位置是圈定有利成矿靶区的关键科学问题。

The continental crust was formed through the continental nucleus, platform, Pangea, continental splitting, continental accretion, intercontinental collision and orogeny in its progress. The crust was split into continental crust and oceanic crust by inhomogeneous differentiation. Continental margins that have different tectonic features were formed by continental splitting, oceanic crust subduction or intercontinental collision. Five marginal tectonic belts, thirteen secondary tectonic regions and fifty-three space-time distribution structures were decided according to the distribution of three intercontinental collision belts. The probabilities for discovering ore deposits in tectonic regions were calculated based on existing deposits. Continental margins were divided into divergence type, convergence type, collision type and transform type, and their metallogenetic serial specialization was summarized. It's very important for metallogeny to occur where advantaged metallogenetic multiple factors were coupled. Their coupling mechanism and space-time distribution in continental margin are key to outlining advantaged metallogenetic area.