Collaborative Research: The M7.8 Simeonof earthquake: Untangling Slip from Seconds to Years across the edge of the Shumagin Seismic Gap

地球上最大的地震发生在一个板块推到另一个板块下方的地方。在美国，这些地震最频繁地发生在阿拉斯加，这使那里成为了解地震断层行为的理想场所。这一合作研究项目将研究最近发生在阿拉斯加舒马金群岛的2020年7月22日西蒙诺夫地震，以了解地震前、地震中和地震后断层滑动的特征。他们将确定地震期间和地震后断层滑动的分布，并将其与地震前的断层滑动分布进行比较。他们还将使用阿拉斯加两栖社区地震实验的数据来更准确地定位板块界面，那里发生了滑动。该项目还将与当地小学合作，为小学生开发与地震有关的培训材料。研究人员将收集三种类型的数据，外加使用NSF的Gage设施提供的数据。他们将在阿拉斯加舒马金群岛的几个岛屿上测量测量标记的位置，并在其中几个位置安装持续运行的GPS站点。这些数据将显示由于地震和持续的震后滑动，地面永久移动了多少。他们将用重复通过卫星雷达干涉测量的地面运动测量来补充这些测量结果。最后，研究人员将使用阿拉斯加两栖社区地震实验的地震数据来更准确地定位板块界面上的地震，并使用下行太平洋板块内的地震来确定板块界面的位置和几何形状。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The largest earthquakes on the planet occur where one plate pushes beneath another. In the United States, these earthquakes happen most frequently in Alaska, making that an ideal place to learn about how earthquake faults behave. This collaborative research project will study the recent 22 July 2020 Simeonof earthquake, located in the Shumagin Islands, Alaska, to learn about the character of fault slip before, during, and after earthquakes. They will determine the distribution of fault slip during and following the earthquake, and compare it with the distribution of fault slip before the earthquake. They will also use data from the Alaska Amphibious Community Seismic Experiment to more precisely locate the plate interface, where the slip occurs. The project will also develop training materials related to earthquakes for elementary students in partnership with local elementary schools.The researchers will collect three types of data, plus use data provided by NSF’s GAGE facility. They will measure the locations of survey markers on several islands of Alaska’s Shumagin Islands, and install continuously operating GPS sites at several of those locations. These data will show how much the ground moved permanently due to the earthquake and due to ongoing post-earthquake slip. They will complement these measurements with measurements of ground movements from repeat-pass satellite radar interferometry. Finally, the researchers will use seismic data from the Alaska Amphibious Community Seismic Experiment to locate earthquakes on the plate interface more precisely, and to use earthquakes within the downgoing Pacific plate to determine the location and geometry of the plate interface.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.