Enhancing Diversity in the Geosciences by Testing the Rigidity of the Eurasia Plate Using GPS

利用 GPS 测试欧亚板块的刚性，增强地球科学的多样性

• 批准号: 1347561
• 负责人: Richard Bennett
• 金额: $ 17.17万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-15 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1347561&HistoricalAwards=false
• 关键词: Enhancing; Diversity; Geosciences; Testing; Rigidity

Preliminary analyses of GPS-derived crustal motions from 251 continuous GPS stations in west and central Europe cast doubt on the rigidity of western Eurasia. Possible belts of concentrated deformation appear to coincide with prominent seismically active and/or geologically distinct features, such as the Trans-European Suture Zone, the Rhine Graben, and the Pyrenees Mountain belt. But the motions are small and many additional tests of the internal kinematics of the region are required. This project exploits existing data from hundreds of continuously operating GPS stations located in west and central Europe to determine whether or not intraplate seismicity is accompanied by observable intraplate deformation. The project involves: (1) acquisition and analysis of new data from existing continuous GPS networks in Europe and the Mediterranean region; and (2) statistical tests of western Eurasia plate rigidity in order to explore possible explanations for observed crustal motions such as microplate motion, interplate and inter-microplate elastic strain accumulation, diffuse intraplate deformation, ephemeral strain accumulation associated with glacial isostatic adjustment, site specific secular motion, and time correlated measurement error. The science objectives will provide an opportunity to attract new Geoscience majors with physical disabilities, an important underrepresented group in the Geosciences. Specifically and in conjunction with the University of Arizona Disability Resource Center, the project will (1) increase awareness of Geoscience research opportunities; (2) develop strong mentoring relationships between undergraduate students with physical disabilities and more senior researchers; and (3) create meaningful undergraduate research experiences, including hypothesis testing and dissemination of results at a student-run symposium and at national level scientific conferences.The main objective of this project is to test the internal rigidity of the western Eurasia plate. The theory of plate tectonics is based upon the idea that relative motion between adjacent plates is accommodated mostly within narrow zones of intense deformation. However, abundant intraplate seismicity and strain accumulation observed by space geodesy indicates that this hypothesis is not strictly valid. Where plate boundaries involve continental lithosphere the zones of interplate deformation may extend hundreds of kilometers into the continental interiors, blurring the distinction between interplate and intraplate deformation. This project exploits existing of data from hundreds of continuously operating GPS stations located in west and central Europe to determine whether or not intraplate seismicity is accompanied by observable intraplate deformation. Understanding the rigidity of continental plate interiors is also important for earthquake hazards assessment because intraplate earthquakes may have very long recurrence periods, and are thus difficult to anticipate. The project will broaden participation and diversity among Geoscience majors by creating meaningful and broadly accessible undergraduate research experiences, including hypothesis testing, and dissemination of results at a student run symposium and at national scientific conferences.

对西欧和中欧251个连续GPS站的GPS地壳运动的初步分析，令人怀疑西欧欧亚大陆的刚性。可能的集中变形带似乎与突出的地震活动和/或地质特征相吻合，如跨欧洲缝合带、莱茵格拉本和比利牛斯山带。但运动很小，需要对该区域的内部运动学进行许多额外的测试。该项目利用位于西欧和中欧的数百个连续运行的GPS站的现有数据来确定板内地震活动是否伴随着可观察到的板内变形。该项目涉及：(1)从欧洲和地中海地区现有的连续全球定位系统网络获取和分析新数据；(2)对欧亚大陆西部板块硬度进行统计测试，以探索对观测到的地壳运动的可能解释，例如微板块运动、板块间和微板块间的弹性应变累积、板内弥散变形、与冰川均衡调整有关的短暂应变累积、特定地点的长期运动和与时间相关的测量误差。科学目标将提供一个机会来吸引新的地球科学专业的肢体残疾学生，这是地球科学中一个重要的代表性不足的群体。具体地说，该项目将与亚利桑那大学残疾资源中心合作，(1)提高对地球科学研究机会的认识；(2)在身体残疾的本科生和更资深的研究人员之间建立牢固的指导关系；(3)创造有意义的本科生研究经验，包括在学生举办的研讨会和国家一级的科学会议上进行假设检验和结果传播。该项目的主要目标是测试欧亚板块西部的内部刚性。板块构造理论是基于这样一种观点：相邻板块之间的相对运动主要是在剧烈变形的狭窄区域内进行的。然而，空间大地测量观测到的丰富的板内地震活动和应变积累表明，这一假设并不严格有效。如果板块边界涉及大陆岩石圈，板块间变形的区域可能延伸到大陆内部数百公里，模糊了板块间变形和板块内变形之间的区别。该项目利用位于西欧和中欧的数百个连续运行的GPS站的现有数据来确定板内地震活动是否伴随着可观察到的板内变形。了解大陆板块内部的刚性对于地震危险性评估也很重要，因为板块内地震可能有很长的重现期，因此很难预测。该项目将通过创造有意义和广泛接触的本科生研究经验，包括假设检验，以及在学生举办的研讨会和国家科学会议上传播结果，扩大地学专业的参与度和多样性。