Examining the mechanical behavior and evolution of the southern San Andreas fault system through determination of late Quaternary slip rates and distinct element simulations

通过确定晚第四纪滑动速率和不同元素模拟来研究圣安德烈亚斯断层系统南部的力学行为和演化

• 批准号: 1049688
• 负责人: Kimberly Blisniuk
• 金额: $ 8.5万
• 依托单位: Blisniuk Kimberly
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2014-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1049688&HistoricalAwards=false
• 关键词: Examining; mechanical; behavior; evolution; southern

Dr. Kimberly Blisniuk has been awarded an NSF Earth Science Post Doctoral Fellowship to carry out a research and education plan at University of California at Berkeley. She will study how deformation within continental strike-slip fault systems is partitioned along and across individual fault strands and fault zones over 1,000s to 100,000s year timescales. More specifically, the project is aimed at understanding the kinematic and mechanical evolution of the San Andreas Fault System in southern California by: (1) mapping offset landforms through wavelet analysis of high-resolution topography data and geologic fieldwork, (2) dating displaced landforms to obtain precise estimates of fault slip rates at multiple time scales by applying terrestrial cosmogenic nuclide exposure age dating of surface clasts and U-series dating of pedogenic carbonate coatings on subsurface clasts, and (3) using those observations to formulate first-order distinct element models simulating the behavior and interactions of faults observed in the field.A particularly promising aspect of this study is that cosmogenic nuclide dating and U-series dating are relatively new dating methods that can be used to reliably date late Quaternary sediments and landforms measurably offset along active faults. Prior to the development of these methods, the dating of fault motion has only been possible at the time scales of geodetic and paleoseismological studies, typically years to thousands of years, or from total displacements of geological units over hundreds of thousands to millions of years. As these new dating techniques permit the dating of fault displacements at time scales of thousands to several hundreds of thousands of years, they provide the "missing link" that existed in geochronologic studies of fault systems. Accordingly, detailed studies of fault systems during this time interval combined with mechanical models that mimic the behavior of faults observed in the field can reveal previously unrecognized aspects of fault mechanics and fault system evolution. Such information can be used to refine and improve models for earthquake recurrence used in assessing seismic hazards. This fellowship will not only develop K. Blisniuk's skills as a researcher but it will also further her skills as an educator through her co-teaching of upper division geology courses and mentoring of undergraduate and graduate students in neotectonic and geochronologic studies at the University of California, Berkeley.

Kimberly Blisniuk博士被授予NSF地球科学博士后奖学金，在加州大学伯克利分校开展研究和教育计划。她将研究大陆走滑断层系统内的变形是如何沿着沿着和跨越个别断层链和断层带在1,000到10万年的时间尺度上划分的。 更具体地说，该项目旨在通过以下方式了解加州南部圣安德烈亚斯断层系统的运动学和力学演化：（1）通过高分辨率地形数据的小波分析和地质野外工作绘制偏移地貌，（二）通过对地表碎屑和U-同位素的地球宇宙成因核素暴露年龄测定，确定移位地貌的年龄，以获得多个时间尺度上断层滑动速率的精确估计。地下碎屑上成土碳酸盐涂层的系列测年，（3）利用这些观测结果建立一阶离散单元模型，模拟野外观测到的断层行为和相互作用。系列测年法是一种相对较新的测年方法，可用于可靠地测定晚第四纪沉积物和地貌的年代，这些沉积物和地貌可测量地沿活动沿着偏移断层 在这些方法发展之前，断层运动的年代测定只能在大地测量学和古地震学研究的时间尺度上进行，通常是几年到几千年，或者从几十万年到几百万年的地质单元的总位移中进行。 由于这些新的测年技术允许在数千至数十万年的时间尺度上测定断层位移的年代，它们提供了断层系统地质年代学研究中存在的“缺失环节”。 因此，在这段时间内，结合力学模型，模拟在现场观察到的故障的行为，可以揭示以前未被认识的方面的故障力学和故障系统的演化故障系统的详细研究。 这些信息可用于完善和改进用于评估地震危险的地震复发模型。 这个项目不仅能开发K。Blisniuk作为一名研究人员的技能，但它也将进一步她作为一名教育工作者的技能，通过她的合作教学的上层司地质课程和指导本科生和研究生在新构造和地质年代学研究在加州大学伯克利分校。