Collaborative Research: Bear Mountain Intrusive Complex, Klamath Mountains, California: Arc Magmatism and Crustal Anatexis During a Contractional Orogeny

9902807 SnokeArc岩浆活动通常被认为与弧环境中的伸展变形有关，但在某些情况下，它可能与收缩变形有关。 在加州的克拉马斯山脉地区，伸展弧岩浆作用与收缩弧岩浆作用交替发生，前者形成钙碱性岩浆，后者则与富钾岩浆有关。 熊山侵入杂岩包含这些岩体类型及其接触晕。 本研究将讨论岩体和围岩的运动学和应变历史、岩相学和热压学，以便将岩浆成分与构造环境联系起来。 岩石学建模将试图了解岩体和接触带（包括混合岩）的形成和演化。 结果将提供更清晰的了解岩浆成分，构造背景和应变组构的发展之间的联系，无论是熊山复杂的和其他例子弧岩浆活动的收敛和伸展的情况。

9902807SnokeArc magmatism is generally thought to be associated with extensional deformation within the arc environment, but in some instances it can be associated with contractional deformation. In the Klamath Mountains province of California, extension related arc magmatism alternated with contraction-related magmatism, but the former resulted in calc-alkaline magmas whereas the latter was associated with distinctive K20-rich magmas. The Bear Mountain intrusive complex contains these pluton types and their contact aureoles. This study will address the kinematic and strain history, the petrography and thermobarometry of the plutons and wall rocks in order to relate magma composition to tectonic environment. Petrologic modeling will attempt to understand the formation and evolution of the pluton and contact zone, including migmatitic rocks. Results will provide clearer understanding of the links between magma composition, tectonic setting and development of strain fabrics, both for the Bear Mountain complex and other examples for arc magmatism in convergent and extensional circumstances.