Collaborative Proposal: 4-D Assessment of the Earliest Stages of Magmatism in a Continental Margin Arc

0000719 Beard 0001004 Crawford 0001102 Sinha由于会聚构造，外来物质增生到大陆边缘，发生了一些重要的条件变化，其中一些导致岩浆的产生，随后参与了增生的持续结构发展。 英云闪长质岩体通常是在大陆边缘弧增生时生成的，它们的成分提供了源区P-T-X H2O条件的信息，并结合组构和结构数据，提供了对迁移和侵位过程的限制，这些过程可能导致岩浆在穿越和侵位地壳时发生化学改性。 该项目将利用阿拉斯加东南部Revillagigedo岛上的一套英云闪长岩岩体，记录大陆弧岩浆活动的早期阶段。 研究结果有望详细描述和追踪这些岩浆在这种会聚环境中的起源、改造和构造相互作用。

0000719 Beard0001004 Crawford0001102 SinhaAs exotic material accretes to a continental margin by convergent tectonics, a number of important changes in conditions occurs, some of which lead to production of magma that subsequently becomes involved in the ongoing structural development of the accretion. As tonalitic plutons are commonly generated as continental margin arcs accrete, their composition provides information about the P-T-X H2O conditions of the source region, and combined with fabric and structural data, provide constraints for the transport and emplacement processes that might lead to chemical modification of magmas as they traverse and are emplaced in the crust. The project will utilize a suite of tonalitic plutons on Revillagigedo Island in southeastern Alaska that record early stages of continental arc magmatism. Results are expected to detail and track the origin, modification and tectonic interactions of these magmas in this convergent setting.