Slip Rates on the Southern San Andreas Fault: Implications for Neotectonic, Seismic and Geodetic Models

南圣安德烈亚斯断层的滑动率：对新构造、地震和大地测量模型的影响

• 批准号: 0125741
• 负责人: Kerry Sieh
• 金额: $ 2.4万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-04-01 至 2003-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0125741&HistoricalAwards=false
• 关键词: Slip; Rates; Southern; San; Andreas

The PI proposes to determine the slip rate of the San Andreas Fault at several sites in southern California using 10Be and 26Al measurements of the exposure ages of offset geomorphic surfaces. Determination of a millennial slip rate north of Los Angeles, on the flank of the Mojave Desert, would provide a critical constraint to the interpretation of geodetic data there. Rates of slip across the fault on each side of the San Gorgonio Pass stepover would constrain the relative importance of the several strands of the fault in that region. Within the complex restraining stepover, rates and dates of fault slip and folding would test a new model of transpressional deformation. They would do this by constraining the evolution of deformation there throughout the late Quaternary period. A quantitative understanding of active deformation would also provide a basis for forward models of future large earthquakes involving this ominously historically dormant section of the San Andreas Fault.

PI建议使用10Be和26Al测量偏移地貌表面的暴露年龄来确定加利福尼亚州南部几个地点的圣安德烈亚斯断层的滑动速率。确定洛杉矶以北莫哈韦沙漠侧翼的千年滑移率，将对那里的大地测量数据的解释提供关键的限制。圣戈戈尼奥山口跨越区两侧断层的滑动速度将限制该地区断层几股的相对重要性。在复杂的约束跨越中，断层滑动和褶皱的速率和日期将检验一种新的扭压变形模式。他们将通过限制那里的变形在整个第四纪晚期的演化来做到这一点。对活动形变的定量了解也将为未来涉及圣安德烈亚斯断层这一不祥的历史休眠部分的大地震的正演模型提供基础。