Collaborative Research: Subduction and Exhumation of Ulltrahigh-Pressure Rocks -- Field and Drilling Studies in Eastern China

合作研究：超高压岩石的俯冲和折返——中国东部的野外和钻探研究

• 批准号: 0003355
• 负责人: Juhn Liou
• 金额: $ 96.22万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2006-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0003355&HistoricalAwards=false
• 关键词: Collaborative; Research; Subduction; Exhumation; Ulltrahigh

0003355LiouThis project is focused on the area around a 5 km drill hole the Chinese are going to drill in the Sulu ultrahigh-pressure (UHP) metamorphic terrane in east-central China. The goal of the project is to understand the formation and exhumation of UHP rocks through study of ultramafic (mantle) rocks from a "forbidden zone" of P-T conditions (i.e., very high P, very low T). Some specific questions to be addressed are: o What type of crust-mantle interaction occurs when continents are subducted? o How much of continental mass is recycled in this manner? o Can timing of fluid-rock interactions be constrained? o What do the UHP garnet peridotites tell us about "petrotectonic" processes? o How were UHP peridotites emplaced into the crust? How did they evolve during exhumation? What mechanisms and rates of ascent are necessary to preserve their high P, low T assemblages? o What roles do slab hydrous phases play in recycling of volatiles into the mantle? o Can we tell the difference between subduction/collisional architecture of orogens from younger events using deep-seismic profiles? o In what tectonic settings does UHP metamorphism and subsequent exhumation occur? Is continent-continent collision required?The Principal Investigators will employ a variety of methods in their study: 1) mapping and structural analysis; 2) petrology & geochemistry; 3) geochronology; 4) geophysics at the Donghai drill site; and 5) geodynamic modeling.***

0003355LIOUTHIS项目集中在中国东部中部的Sulu Ultrahigh Prassure（UHP）变质地层中，中国人将在5公里的钻孔附近进行钻探。 该项目的目的是通过从P-T条件的“禁区”（即非常高的P，非常低的T）研究超越（地幔）岩石来了解UHP岩石的形成和挖掘。 要解决的一些具体问题是：o在俯冲时发生哪种类型的外壳甲型相互作用？ o以这种方式回收了多少大陆质量？ o流体 - 岩石相互作用的时机可以受到限制吗？ o UHP石榴石橄榄岩告诉我们什么“石油”过程？ o UHP橄榄岩是如何将其放入地壳中的？ 他们在挖掘过程中如何发展？ 保持高P，低T组合需要什么机制和上升速率？ o平板含液相在将挥发物回收到地幔中有什么作用？ o我们能否分辨出使用深度看法的年轻事件的俯冲/碰撞体系结构之间的区别？ o UHP变质和随后的挖掘发生在哪些构造环境中？ 是否需要大陆碰撞？主要研究人员将在其研究中采用多种方法：1）映射和结构分析； 2）岩石学与地球化学； 3）年代学； 4）地球物理学在Donghai演习现场； 5）地球动力学建模。***