Collaborative Research: RAPID: Capturing the Elgin-Lugoff earthquake swarm with a dense nodal array

该RAPID项目涉及在南卡罗来纳州正在进行的埃尔金-卢格夫震群序列的震中区域部署86个Smartsolo 5 Hz节点。该序列始于2021年12月27日的3.3级（M），位于背景地震活动相对较低的地区。这一序列似乎发生在几个事件中，有时由M3+事件引发，并且之间有长达数月的间隙。虽然它们沿着古老的东部皮埃蒙特断层系统发生，但对地震的仔细检查表明，大多数事件发生在断层系统之间。目前还不清楚这次震群的动力是什么，会持续多久，这个部署是及时的，因为这个序列还在进行，没有马上结束的迹象。此外，只有一个站部署在蜂群的几公里范围内。这样的台站分布不足以提供震群期间微震活动的详细高分辨率检测/重新定位，这是更好地破译震群序列及其物理机制的时空演变所必需的。此外，在这次部署中收集的地震数据将用于构建当地地下结构的速度模型。精确的地震模型对于建立地震危险性评估和断层定位的地面运动模型至关重要。来自格鲁吉亚理工学院和南卡罗来纳州大学的多达15名本科生/研究生将参与节点部署。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This RAPID project involves a seismic deployment of 86 Smartsolo 5Hz nodes to the epicenter region of the ongoing Elgin-Lugoff earthquake swarm sequence in South Carolina. This sequence started with a magnitude (M) 3.3 on December 27, 2021, in a region with relatively low background seismicity. This sequence appears to occur in several episodes, sometimes initiated by M 3+ events, and has up to months of gaps in between. While they occurred along the ancient Eastern Piedmont Fault System, a close examination of the earthquakes reveals that most of the events occurred in between the fault system. At this point, it is still not clear what is the driving force for this earthquake swarm and how long it will last.This deployment is timely, because this sequence is still ongoing, with no signs of ending soon. In addition, only one station was deployed within a few kilometers of the swarm. Such station distribution is not sufficient enough to provide a detailed high-resolution detection/relocation of microseismicity during an earthquake swarm, which are needed for better deciphering the spatio-temporal evolutions of the swarm sequence and their physical mechanisms. In addition, the seismic data collected in this deployment will be used to construct a velocity model of the local subsurface structure. Accurate seismic models are crucial particularly for developing ground motion models for seismic hazard assessment and delineating faultlocations. Up to 15 undergraduate/graduate students from both Georgia Tech and University of South Carolina will be involved in the nodal deployment. Data will be made available through the IRIS Data Management Center.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.