COLLABORATIVE RESEARCH: Tectonothermal Evolution during Collisional Orogenesis: Blueschist to Granulite facies Metamorphism in the Kigluaik Mountains, Alaska

阿拉斯加的Kigluaik山脉包含一个麻粒岩相（高温）变质叠加在相对较冷的高压绿帘石蓝片岩上。两个相互竞争的假说是：（1）它代表了一个伸展变质核杂岩，在不同等级的岩石之间有明显的结构断裂;（2）高温Meta作用是由于增厚地壳的热再平衡而形成的，没有结构断裂。本研究将通过野外工作、岩石学和地质年代学的综合方案直接检验第二种假设。它还将评估高品位岩石的热传输机制。这一结果将对碰撞后造山带深部的热历史提供重要的制约，因而具有广泛的构造意义。

The Kigluaik Mountains in Alaska contain a granulite facies (high-temperature) metamorphic overprint on relatively cool, high pressure, epidote-blueschist rocks. Two competing hypotheses for this juxtaposition are (1) that it represents an extensional metamorphic core complex with a pronounced structural break between the different grade rocks, and (2) that the high temperature meta- morphism formed in response to thermal re-equilibration of thickened crust with no structural break. This study will directly test the second hypothesis by an integrated program of field work, petrology and geochronology. It will also evaluate heat transport mechanisms for the high grade rocks. The results will provide important constraints on the thermal history of deep seated parts of orogens immediately post-collision, and will thus have wide tectonic significance.