COLLABORATIVE RESEARCH: Thermal Evolution of the Maryland Pennsylvania Piedmont: Application of U-Pb Geochronology to Collisional Tectonics

合作研究：马里兰州宾夕法尼亚州皮埃蒙特的热演化：U-Pb 地质年代学在碰撞构造中的应用

• 批准号: 9304708
• 负责人: Maria Crawford
• 金额: $ 8.84万
• 依托单位: Bryn Mawr College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-07-01 至 1998-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9304708&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Thermal; Evolution; Maryland

The thermal evolution of crust margins involved in collisional processes is an important issue in tectonics, as the thermal and physical modification of the crust through thrust stacking and associated magmatism play an important role in the growth of continents. This project will focus on the piedmont of Maryland, Delaware and Pennsylvania where a continental margin arc developed and subsequently collided with the margin with attendant overthickening by thrust stacking and low pressure, high temperature metamorphism. The work will develop the tectonic chronology of the collisional orogen through high precision U-Pb ages of zircons and monazite from rocks that record the overthickening event and associated magmatism. The duration of the entire orogenic cycle from arc stage through thrust stacking to partial melting can be uniquely determined in the study area, and should provide a benchmark assessment of rates of metamorphic-igneous-tectonic processes in a collisional environment.

碰撞过程中涉及的地壳边缘的热演化是构造的一个重要问题，因为通过推力堆积和相关的岩浆作用在地壳中的热和物理修饰在大陆的生长中起着重要作用。 该项目将重点放在马里兰州，特拉华州和宾夕法尼亚州的皮埃蒙特，在那里，大陆边缘弧弧发展，随后与边缘相撞，随之而来的是因推力堆积和低压力，高温质量的过度打击。 这项工作将通过岩石的高精度U-PB年龄来发展碰撞造山基因的构造年代，从岩石中记录了过度冲刺事件和相关的岩浆作用。 从弧阶段到推力堆叠到部分熔化的整个造山周期的持续时间可以在研究区域中确定，并应在碰撞环境中对变质 - 毫无形态的构造过程的速率进行基准评估。