Towards Understanding the Range of Fault Properties that Generate Tremor and Earthquake Activity Along the San Andreas Fault

了解沿圣安德烈亚斯断层产生震颤和地震活动的断层特性范围

• 批准号: 1049609
• 负责人: Danielle Sumy
• 金额: $ 8.5万
• 依托单位: Sumy Danielle F
• 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: 2011-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1049609&HistoricalAwards=false
• 关键词: Towards; Understanding; Range; Fault; Properties

Dr. Danielle F. Sumy has been awarded an NSF Earth Sciences Postdoctoral Fellowship to carry out a research and education plan at the US Geological Survey, Pasadena. This study will investigate the spatial and temporal distribution of earthquake and tremor activity along the Parkfield - Cholame segment of the San Andreas Fault. Tremor, a long duration low-frequency seismic signal, occurs at deeper depths than traditional earthquake activity and can illuminate the transition between the shallow, earthquake generating portions of the fault and the deeper stable-sliding regime. She will first locate earthquake and tremor signals from seismic waveform data recorded by the temporary Parkfield Experiment to Record MIcroseismicity and Tremor (PERMIT) array. The PERMIT array consists of thirteen densely-spaced seismometers centered directly over the zone of tremor activity, and augments existing seismic networks in this area. Accurate locations of earthquake and tremor activity will allow for an assessment of how much deformation is accommodated via tremor versus earthquake activity. Finally, these results will allow for a detailed investigation into the relationship between tremor and earthquakes, and whether tremor has a part in nucleating earthquake activity or vice versa. The aim of the experiment is to advance our understanding of how the shallow and deeper portions of the San Andreas Fault communicate with one another, and to shed light on the range of fault properties that generate earthquake and tremor activity at this site.Since the first observations of tremor made almost a decade ago, the conditions necessary to generate tremor activity, and whether earthquakes and tremor are generated by the same processes, is hotly debated. Through this research, the entire range of fault behaviors from the earthquake-generating to silently-slipping portions of the San Andreas Fault, as well as the conditions necessary to generate and trigger earthquake and/or tremor activity, will be better understood. Outreach and educational activities associated with this research involve introducing the Quake-Catcher Network (QCN) to K-12 schools and teacher workshops. The QCN is widely distributing seismic sensors throughout K-12 schools and the general public to engage students in scientific research by directly involving them in data collection and interpretation. Additionally, her own research into the relationship between earthquakes and tremor will be introduced through an activity named "Earthquake Science Through Sound". As part of the activity, the entire spectrum of seismic activity from regular earthquakes to tremor to silent earthquakes will be introduced through musical instruments and through the conversion of seismograms to sound.

Danielle F.博士Sumy获得了NSF地球科学博士后奖学金，在帕萨迪纳的美国地质调查局开展研究和教育计划。本研究将探讨地震和震颤活动的空间和时间分布沿着帕克菲尔德-乔莱姆段的圣安德烈亚斯断层。震颤是一种持续时间较长的低频地震信号，发生在比传统地震活动更深的深度，可以照亮断层的浅层地震发生部分与更深的稳定滑动状态之间的过渡。她将首先从临时帕克菲尔德实验记录微震和震颤（PERMIT）阵列记录的地震波形数据中定位地震和震颤信号。PERMIT阵列由13个密集分布的地震仪组成，中心直接位于地震活动区，并增强了该地区现有的地震网络。地震和震颤活动的准确位置将允许评估通过震颤与地震活动适应多少变形。最后，这些结果将允许一个详细的调查震颤和地震之间的关系，以及震颤是否有一部分，在成核地震活动，反之亦然。该实验的目的是促进我们对圣安德烈亚斯断层的浅部和深部如何相互沟通的理解，并阐明在该地点产生地震和震颤活动的断层性质的范围。自从近十年前首次观察到震颤以来，产生震颤活动的必要条件，以及地震和震颤是否是由同一过程产生的，这是一个激烈的争论。通过这项研究，将更好地了解从圣安德烈亚斯断层的地震生成到无声滑动部分的整个断层行为范围，以及生成和触发地震和/或震颤活动所需的条件。与本研究相关的推广和教育活动包括向K-12学校和教师研讨会介绍网络捕手（QCN）。QCN正在K-12学校和公众中广泛分发地震传感器，通过直接让学生参与数据收集和解释来吸引他们参与科学研究。此外，她还将通过一项名为“声音中的地震科学”的活动介绍自己对地震和震颤之间关系的研究。作为活动的一部分，将通过乐器和通过将地震图转换为声音来介绍从常规地震到震颤再到无声地震的整个地震活动范围。