RAPID: Collaborative Research: Seismic Response to the 2016 M5.8 Pawnee Earthquake

RAPID：协作研究：2016 年 M5.8 波尼地震的地震响应

• 批准号: 1664286
• 负责人: Kathleen Keranen
• 金额: $ 2.39万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-11-01 至 2019-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1664286&HistoricalAwards=false
• 关键词: RAPID; Collaborative; Research; Seismic; Response

Induced earthquakes, or seismicity caused by human activity such as wastewater injection or secondary oil recovery, have been increasing in the midwestern United States since 2009. The state of Oklahoma has become known as "the new earthquake capital", with earthquake rates of M3 exceeding those of California in the last few years. The 3 September 2016 Mw5.8 Pawnee, Oklahoma earthquake occurred within the region of induced seismicity, near wastewater disposal wells, and was the largest earthquake ever recorded within the state. The earthquake occurred five years after the second largest earthquake, the similarly sized Mw5.7 November 2011 Prague earthquake. Near Pawnee, local residents reported strong ground-shaking, damage to houses, cracks on the ground, and concerns about safety. Students from Cornell University and Colombia University, in collaboration with local universities including the University of Oklahoma, Oklahoma State University, and University of Tulsa, actively participated in the rapid deployment of 25 seismic stations around the epicentral region. Students of the institutions involved have been actively involved in learning about sensors, network designs, and earthquake physics. The main fault the ruptured during the Pawnee event was an unmapped fault intersecting mapped Labette Fault, which has hosted a significant number of aftershocks include the largest aftershock (M3.9). The aftershock sequence and related seismic activity in the region that has been recorded since the rapid (within 2 days) deployment of seismic instrumentation will help study aftershocks and the likely triggered seismicity on the regional fault systems. In the coming weeks, we will deploy an additional 20 short-period stations that will record data for 12 months. This combined network will provide information on fault structure, aftershock decay, duration, and interaction with injection rate variations. The data will help to understand the characteristics of faults that host large damaging earthquakes, and will help to assess earthquake hazards in Oklahoma and the midcontinent. The broader impact of this rapid deployment will help understand the regional tectonic framework in northern Oklahoma and may elucidate the relationship between this recent seismic activity with the fluid injection activities in the region.

自2009年以来，美国中西部诱发地震，即由废水注入或二次采油等人类活动引起的地震活动不断增加。俄克拉荷马州已成为“新地震之都”，近几年M3级地震发生率超过了加利福尼亚州。 2016 年 9 月 3 日，俄克拉荷马州波尼 Mw5.8 地震发生在废水处理井附近的诱发地震活动区域内，是该州有记录以来最大的地震。这次地震发生在第二大地震（2011 年 11 月布拉格 Mw5.7 类似规模的地震）五年后。波尼附近，当地居民报告了强烈的地面震动、房屋受损、地面裂缝以及对安全的担忧。康奈尔大学、哥伦比亚大学的学生与俄克拉荷马大学、俄克拉荷马州立大学、塔尔萨大学等当地大学合作，积极参与震中地区周边25个地震台站的快速部署。相关机构的学生积极参与传感器、网络设计和地震物理学的学习。波尼事件期间破裂的主要断层是未绘制的断层，与绘制的拉贝特断层相交，该断层发生了大量余震，包括最大的余震 (M3.9)。自快速（2天内）部署地震仪器以来记录的该地区的余震序列和相关地震活动将有助于研究余震和区域断层系统上可能引发的地震活动。在接下来的几周内，我们将另外部署 20 个短期站，记录 12 个月的数据。该组合网络将提供有关断层结构、余震衰减、持续时间以及与注入率变化的相互作用的信息。这些数据将有助于了解发生大破坏性地震的断层的特征，并将有助于评估俄克拉荷马州和中部大陆的地震危害。这种快速部署的更广泛影响将有助于了解俄克拉荷马州北部的区域构造框架，并可能阐明最近的地震活动与该地区的流体注入活动之间的关系。