Collaborative Research: Geodetic Constraints on the Kinematics of the Colorado Plateau and its Western and Southern Margin

合作研究：科罗拉多高原及其西缘和南缘运动学的大地测量约束

• 批准号: 0951731
• 负责人: Richard Bennett
• 金额: $ 29.51万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0951731&HistoricalAwards=false
• 关键词: Collaborative; Research; Geodetic; Constraints; Kinematics

Collaborative Research: Geodetic Constraints on the Kinematics of the Colorado Plateau and its Western and Southern MarginThe Colorado Plateau, southwestern United States, has played an important role in the geologic evolution of the Pacific-North America plate boundary zone. Unlike most other parts of the western U.S., the Colorado Plateau has remained largely intact during most of its geologic history. Indeed, the area shows little to none active earthquake faults. However, earthquakes do happen within the Colorado Plateau, and some very large ones have occurred in southern Arizona and northern Mexico.This project uses precise GPS measurements to establish how the crust of the Colorado Plateau moves relative to stable North America. Interpretation of the horizontal velocities tells the investigators whether the area moves as a coherent block or is internally deforming. In case of the former little earthquake activity is expected, and in case of the latter the seismic hazard in the region may be higher than currently thought. The deformation implied by the GPS data and earthquake data is compared in order to assess whether the earthquake activity can be related to the deformation measured in this project or whether they are due to other processes, such as gravitational collapse. To perform the measurements, 33 new GPS stations are installed in Arizona, southern Utah and southeastern Nevada. These stations complement and densify the long-running continuous GPS stations of NSF EarthScope's Plate Boundary Observatory. The additional stations are needed to create well-constrained models to describe the region's present-day tectonics. With a well-constrained model of the deformation can the origin of the motion and deformation of the Colorado Plateau be investigated. Some of the models that are considered include a rigid motion of the plateau causing opening of the Rio Grande Rift, crustal extension encroaching into the plateau due to evolving mantle processes, and the effect of Pacific plate motion on the deformation of the southern Basin and Range.Many of the new GPS stations are installed in National Parks and Monuments, as well as in State Parks. The investigators provide educational material to inform the parks on the active tectonics of the region and the aim of the project. The goal of these outreach activities is to educate the parks' visitors that the geologic wonderland they are in is actively changing due to geologic processes. Measurements are made for four years and the project involves training of a graduate student. The outcome of this project may be used in a reassessment of the seismic hazard in the region?s urban centers.

合作研究：对科罗拉多高原及其西部和南部边缘的科罗拉多州科罗拉多高原的大地限制在美国西南部，在太平洋 - 北美板块边界区的地质进化中发挥了重要作用。与美国西部的大多数地区不同，科罗拉多高原在其地质历史的大部分历史中都在很大程度上保持完整。 确实，该区域几乎没有发生主动地震断层。但是，科罗拉多高原确实发生了地震，在亚利桑那州南部和墨西哥北部发生了一些非常大的地震。该项目使用精确的GPS测量来确定科罗拉多高原的外壳如何相对于稳定的北美。水平速度的解释告诉研究者该区域是作为连贯的块移动还是内部变形。如果预计前几个地震活动，那么在后者的情况下，该地区的地震危害可能高于目前的想象。比较了GPS数据和地震数据所隐含的变形，以评估地震活动是否可以与该项目中测得的变形有关，或者它们是否是由于其他过程（例如重力崩溃）所致。为了进行测量，在亚利桑那州，犹他州南部和内华达州东南部安装了33个新的GPS站。这些电台补充并致密NSF Earthscope板边界观测站的长期连续GPS站。需要其他站点来创建良好的模型来描述该地区当今的构造学。使用良好的变形模型，可以研究科罗拉多高原运动的起源和变形。一些被认为的模型包括高原的僵化运动，导致里奥格兰德裂谷的开放，由于不断发展的地幔过程而侵占高原的地壳延伸，以及太平洋板运动对南部盆地和南部盆地变形的影响。新的GPS站的变形。调查人员提供教育材料，以告知公园该地区的积极构造和该项目的目的。这些外展活动的目的是教育公园的游客，他们所处的地质仙境正在积极变化，这是由于地质过程的变化。进行了四年的测量，该项目涉及培训研究生。该项目的结果可用于重新评估该地区城市中心的地震危害。