Geomorphic Development and Neotectonic Deformation of Paleolake Coasts in the Eastern Great Basin

东部大盆地古湖岸地貌发育与新构造变形

• 批准号: 8721114
• 负责人: Donald Currey
• 金额: $ 15.07万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-02-15 至 1992-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8721114&HistoricalAwards=false
• 关键词: Geomorphic; Development; Neotectonic; Deformation; Paleolake

This project will (1) reconstruct regional patterns of late Pleistocene coastal processes and coastal chronology in the eastern Great Basin, (2) survey 300 to 400 vertical control points on selected shorelines having relatively well constrained ages, (3) use those surveryed shorelines as long-baseline tiltmeters to reconstruct regional and local isostatic and seismotectonic deformation; (4) and model those data to constrain the mechanical/rheological properties of the earth. Recent studies of coastal chronology and shoreline morphometry in the basins of Lake Bonneville and two nearby paleolakes indicate that deformation of late Pleistocene shorelines resulted mainly from loads imposed by Lake Bonneville, but probably included far-field responses to loads imposed by continental ice sheets. This study will vastly expand the existing data set, to include the deformation of transgressive, maximum-stage, and regressive shorelines of the last deep-lake cycle in 16 paleolake basins in the eastern Great Basin. Studies of coastal chronology and coastal geomorphology will be combined with vertical control surveying using an electronic distance measuring theodolite to define the spatial and temporal dimensions of post-lacustrine deformation. At the Lunar and Planetary Institute, the observed deflections (shoreline tilt) will be modelled as the response of a layered elastic/visco-elastic earth to loads imposed by the small lakes, the much larger Lake Bonneville, and the still more massive but more distant Laurentide and Cordilleran ice sheets.

本项目将(1)重建大盆地东部晚更新世海岸过程和海岸年代学的区域格局；(2)在年龄约束相对较好的选定海岸线上测量300 ~ 400个垂直控制点；(3)利用这些海岸线作为长基线倾斜仪重建区域和局部均衡和地震构造变形；(4)并对这些数据建模，以约束地球的力学/流变特性。最近对Bonneville湖和附近两个古湖泊盆地的海岸年代学和海岸线形态测量学的研究表明，晚更新世海岸线的变形主要是由Bonneville湖施加的载荷引起的，但可能包括对大陆冰盖施加的载荷的远场响应。本研究将极大地扩展现有的数据集，包括大盆地东部16个古湖盆末次深湖旋回的海侵、最大期和退退岸线的变形。海岸年代学和海岸地貌学的研究将与使用电子距离测量经纬仪的垂直控制测量相结合，以确定湖后变形的时空维度。在月球和行星研究所，观测到的偏转（海岸线倾斜）将被模拟为层状弹性/粘弹性地球对小湖泊、大得多的博纳维尔湖以及更大但更远的劳伦泰德和科迪勒兰冰盖施加的载荷的响应。