Metallogeny of convergent and collisional plate margins through geological time

会聚和碰撞构造板块边缘，一个板块俯冲到另一个板块之下或与另一个板块碰撞，是地壳物质返回地幔的唯一位置。这些物质包括水、硫和氯等挥发物，它们对地幔岩浆中金属的增溶和运输至关重要，当它们侵位到上地壳时，它们作为热液再次从这些岩浆中释放出来。斑岩型Cu±Mo±Au和浅成热液型Au±Cu2+矿床形成于这些流体的流动充分集中和体积大的地方，从而导致矿石矿物以经济浓度沉淀。虽然近年来在矿石沉积过程方面取得了重大进展，但产生“肥沃”岩浆(即有可能形成矿床的岩浆)的潜在岩浆和构造过程却不太了解，也不太能很好地纳入成矿模型。这项提议的目的是汇集和扩大对俯冲和碰撞带构造和岩浆作用的研究，重点是限制影响金属行为的过程。这是一项巨大的努力，我将与其他具有专业知识的研究人员合作，以实现这些目标。具体的研究领域将是：显生宙俯冲和后俯冲成矿过程在地球系统范围内的作用；岩浆弧下地壳根部的成矿作用，在那里可以观察到罕见的暴露情况下对地幔衍生金属进行深加工的证据；稀有的前寒武纪斑岩矿床，它可能保存有随地质时代变化的构造-岩浆作用的证据及其对成矿的影响。

Convergent and collisional tectonic plate margins, where one plate subducts beneath or collides with another, are the only locations where crustal materials are returned to the mantle. These materials include volatiles such as water, sulfur, and chlorine, which are critical for the solubilization and transport of metals in mantle-derived magmas, and which are exsolved again as hydrothermal fluids from those magmas upon emplacement in the upper crust. Porphyry Cu±Mo±Au and epithermal Au±Cu ore deposits are formed where the flow of these fluids is sufficiently focused and voluminous to result in precipitation of ore minerals in economic concentrations. While major advances have been made in recent years relating to ore depositional processes, the underlying magmatic and tectonic processes that give rise to “fertile” magmas (i.e., magmas with the potential to form ore deposits) are less well understood, and less well integrated into metallogenic models. The objective of this proposal is to draw together and extend research on subduction and collision zone tectonics and magmatism, with a focus on constraining the processes that affect the behaviour of metals. This is a large endeavour, and I will work collaboratively with other researchers with specialist expertise to achieve these goals. Specific areas of research will be: Phanerozoic subduction and post-subduction ore-forming processes at an Earth-system scale; the metallogeny of the lower crustal roots of magmatic arcs, where evidence for deep processing of mantle-derived metals can be observed in rare exposures; and rare Precambrian porphyry deposits that may preserve evidence of changing tectonomagmatic processes over geological time, and their effects on metallogeny.