Integrating Geologic, Geodetic, and Coastal Tide Gauge Observations with 100-year Vertical Deformation Models of California Earthquake History

将地质、大地测量和沿海验潮观测与加州地震历史 100 年垂直变形模型相结合

• 批准号: 0838252
• 负责人: Bridget Smith-Konter
• 金额: $ 23.08万
• 依托单位: University of Texas at El Paso
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-15 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0838252&HistoricalAwards=false
• 关键词: Integrating; Geologic; Geodetic; Coastal; Tide

This project investigates earthquake-induced vertical deformation using a synthesis of coastal tide gauge, geodetic, and geologic data of the Pacific-North American plate boundary. While the growing archive of space geodetic data in this region provides precise deformation measurements with a high degree of spatial coverage, these data supply only a 15-year record of crustal motions and therefore only weakly constrain time-dependence of crustal motions. Geologic data provide a 1000-year averaged record of deformation, however these data are often sparsely located and can have large uncertainties. Alternatively, sea level change has been continuously recorded along the California coastline at several tide gauge stations for over the past 50-100 years. These stations provide a temporal record of sea level change, generally attributed to post-glacial rebound and ocean climate phenomena. However, geologic processes, including displacements from large earthquakes, have also been shown to produce sea level variations, as vertical interseismic strain accumulation can contribute uplift and subsidence rates of 1-3 mm/yr. Using coastal tide gauge time series data, this project is exploring the correlation between sea level variations and estimates of vertical displacements produced by a three-dimensional earthquake cycle deformation model that is constrained by geologic slip rates, geodetic velocities, and historical seismic data along the San Andreas fault system. First order vertical deformation estimates derived from geologically and geodetically constrained models are highly compatible with long-term sea level trends, however further analysis is needed to thoroughly explore model parameter space and investigate sources of misfit and unmodeled phonomena. The project will integrate 100-year coastal tide gauge data (Permanent Service for Mean Sea Level), geodetic data (EarthScope Plate Boundary Observatory continuous GPS and InSAR) spanning the last 15 years, and a new geologic database (Southern California Earthquake Center Geologic Vertical Motion Map).This study investigates the long-term role of tectonic deformation on sea level change recorded over the past 100 years along the California coastline. In doing so, these research activities contribute to the objectives of NSF?s EarthScope Initiative by further advancing our understanding of fault system crustal dynamics, earthquake hazards, and data synthesis. The data and model products generated by this investigation will provide an enhanced infrastructure for education and public awareness of both past and present earthquake hazards in California. Furthermore, because a major California earthquake has the potential for massive economic and human loss, quantitative seismic hazard estimates, which rely on an accurate characterization of tectonic motions in California, are critical to the advancement of earthquake science.

该项目通过使用沿海潮汐量表，大地测量学和太平洋北美板块边界的沿海潮汐量表，地质数据的合成来研究地震诱导的垂直变形。尽管该区域的空间大地数据的日益增长的档案提供了具有高度空间覆盖的精确变形测量值，但这些数据仅提供15年的地壳运动记录，因此仅限制了地壳运动的时间依赖性。地质数据提供了1000年的平均变形记录，但是这些数据通常位置稀疏，并且可能具有较大的不确定性。另外，在过去的50 - 100年中，在加利福尼亚海岸线上一直在加利福尼亚海岸线上不断记录海平面变化。这些站点提供了海平面变化的时间记录，通常归因于冰川后反弹和海洋气候现象。然而，由于垂直的经过震荡应变的积累可以促进1-3 mm/yr的垂直瞬变，包括大地震的位移，包括大地震的位移，包括大地震的位移。使用沿海潮汐量规时间序列数据，该项目正在探索海平面变化与由三维地震周期变形模型产生的垂直位移之间的相关性，该模型受地质滑移速率，地质速度，地质速度和沿San Andreas断层系统沿线的历史震颤数据约束。一阶垂直变形估计值是从地质和地质约束模型中得出的，与长期的海平面趋势高度兼容，但是需要进一步的分析来彻底探索模型参数空间并研究不合适和未模块化的Phonomena的来源。该项目将整合过去15年的100年沿海潮汐量表数据（平均海平面的永久服务），地球板数据（Earthscope板边界观测值连续GP和Insar），以及新的地质数据库（南加州地震中心地震中心的地质垂直垂直图）。这项研究研究了该层次沿海层面上的沿海层面上的研究，该研究均在统计级别上进行了100年的统一沿岸的作用。通过这样做，这些研究活动为NSF的EarthScope倡议的目标做出了贡献，它进一步推进了我们对断层系统地壳动态，地震危害和数据综合的理解。该调查产生的数据和模型产品将为加利福尼亚州的过去和现在地震危害提供增强的基础设施和公众对过去和现在的地震危害的认识。此外，由于加州的主要地震具有大规模经济和人类损失的潜力，因此依赖加利福尼亚州构造运动的准确表征的定量地震危害估计对于地震科学的发展至关重要。