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

阿拉斯加的Kigluaik山脉在相对凉爽、高压的绿帘蓝片岩上覆有麻粒岩相（高温）变质岩。对于这种并置，有两种相互竞争的假设：(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构造断裂；(2)高温变质态形成于加厚地壳的热再平衡，没有构造断裂。这项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递机制。研究结果将为研究造山带深部碰撞后的热史提供重要的约束条件，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.