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

该项目将继续对中国超高压地层研究过程中获得的岩心和露头样品进行地球化学和年代分析。中国大陆钻探工程（CCSD）在苏鲁地体东海地区开展，为研究这一重要带提供了独特的三维研究机会。钻探工作刚刚结束，几个浅孔和一个5公里深的钻孔已经完成。大别-苏鲁带的野外研究和钻孔样品的初步研究，对大陆物质的俯冲掘出过程和高P -低T变质作用过程提供了许多新的认识；目前是地球科学的“热门话题”。具体而言，大别-苏鲁缝合带似乎是世界上解决地壳岩石被带到100公里以上深度然后返回地表的条件以及地幔岩石如何从200公里深处运输到浅层并融入俯冲大陆板块或山带的问题的最佳地点之一。该项目是PI与中国同事长期合作的延续，他们在钻井中发挥了重要作用。美国的主要任务是对岩心样本进行详细的矿物学研究。

0507331RumbleThis project will continue geochemical and chronological analyses of drill core and outcrop samples obtained in the course of studying an ultrahigh-pressure (UHP) terrane in China. The Chinese Continental Drilling Project (CCSD), in the Donghai area of the Sulu terrane, provides a unique opportunity to study this important belt in three dimensions. The drilling is just now winding up with the completion of several shallow holes and one 5-km deep borehole. Field studies of the Dabie-Sulu belt and the initial studies of borehole samples have provided many new insights into the processes involved in the subduction and exhumation of continental material and into the processes of high P - low T metamorphism; presently a "hot topic" in earth sciences. Specifically, the Dabie-Sulu suture zone appears to be one of the best places in the world to address the conditions under which crustal rocks are taken to depths of more than 100 km and then returned to the surface, as well as the question of how mantle rocks from depths of 200 km are transported to shallow depths and incorporated into subducted continental slabs or mountain belts. The project is the continuation of the PI's long term collaborations with Chinese colleagues who have played a major role in the drilling. The major US role involves detailed mineralogical studies of drill core samples.