CAREER: Induced seismicity: Increasing understanding of fluids in fault zones and engaging stakeholders for rapid knowledge transfer

职业：诱发地震活动：增进对断层带流体的了解并让利益相关者参与快速知识转移

• 批准号: 1554846
• 负责人: Kathleen Keranen
• 金额: $ 58.5万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-02-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1554846&HistoricalAwards=false
• 关键词: CAREER; Induced; seismicity; Increasing; understanding

Earthquakes occurring near oil and gas production wells have surged in number and public visibility within the US in recent years. These earthquakes may be triggered by pressure changes in subsurface rock layers resulting from injection or withdrawal of fluids, and are referred to as induced seismicity. These earthquakes pose a hazard to local residents and create challenges for energy production. However, despite recent research, we remain unable to determine, prior to injection, whether wells in a given area are likely to induce earthquakes, and if so, of what number and magnitude. This research seeks to determine the primary factor(s) controlling the triggering of induced seismicity, to test seismic methods of detection of increased fluid pressure along subsurface fault zones that may potentially increase seismic risk, and to investigate whether faults produce detectable seismic signals during the initiation of fault slip during moderate earthquakes. Results from this research will be combined with related studies to provide current and unbiased scientific information regarding induced seismicity to stakeholders, such as local residents, oil and gas regulators, oil and gas corporations, or scientists advising these groups. The results will have broad global significance for energy resource development since induced seismicity has occurred in association with wastewater disposal wells, hydraulic fracturing operations, geothermal stimulation, gas production, and gas storage. Induced seismicity is a potential challenge for long-term carbon storage in the subsurface, one of the primary solutions proposed to remove carbon dioxide from the atmosphere, thus mitigating the impacts of climate change. Results from this research may also provide insight into the processes by which fault slip initiates during earthquakes.This research will acquire seismic data using long-term and dense passive seismic networks, encompassing regions of high-volume wastewater disposal near known large faults. Data will be used to monitor the seismic or aseismic nature of pressure propagation away from active wells, and to probe the seismic responsiveness of the local faults. Forty-five broadband seismometers will be deployed at about 5 km spacing in two 18-month deployments, first in Oklahoma and subsequently in a complementary region of active fluid injection. Within the spatial footprint of the first deployment, a high-density array will be deployed over actively evolving seismicity. Specifically, the research will address 1) whether dense arrays are capable of continuously mapping pressure migration fronts away from wastewater disposal wells by detecting signals from fluid pressure migration; 2) the degree to which this migration is focused along a narrow pathway of faults/fractures, or dispersed over multiple pathways; 3) whether large fault zones are seismically reactive to the larger nearby earthquakes; and 4) whether seismic source characteristics change temporally as fluid pressure increases. The region within north-central Oklahoma includes active seismicity, large disposal wells, and a major fault system. In the second region, with a contrasting geological environment, this research will test and refine methods to detect signals of high fluid pressure approaching faults. Results from both deployments will be synthesized in the global context of induced seismicity. This research seeks to engage local residents and to help them become more confident in finding the information necessary to make informed decisions important in their lives. The scientific results will be communicated to stakeholders, within the context of a frequently updated synthesis of research completed by other groups. This work will engage next-generation leaders in the fields of hazards and resources across geoscience and engineering.

近年来，在美国，发生在油气生产威尔斯井附近的地震数量激增，公众可见度也在上升。这些地震可能是由地下岩石层的压力变化引起的，这些压力变化是由流体的注入或抽出引起的，这些地震被称为诱发地震。这些地震给当地居民带来了危险，并给能源生产带来了挑战。然而，尽管最近的研究，我们仍然无法确定，在注入之前，是否威尔斯井在一个给定的地区可能会引发地震，如果是这样，什么数量和规模。这项研究旨在确定控制诱发地震活动触发的主要因素，测试沿沿着可能增加地震风险的地下断层带增加的流体压力的地震检测方法，并调查在中等地震期间断层滑动开始期间断层是否产生可检测的地震信号。这项研究的结果将与相关研究相结合，为利益相关者提供有关诱发地震活动的最新和公正的科学信息，如当地居民，石油和天然气监管机构，石油和天然气公司或为这些团体提供建议的科学家。这些结果将对能源开发具有广泛的全球意义，因为诱发地震活动与废水处理威尔斯井、水力压裂作业、地热刺激、天然气生产和天然气储存有关。诱发地震活动是地下长期碳储存的一个潜在挑战，而地下长期碳储存是从大气中去除二氧化碳从而减轻气候变化影响的主要解决方案之一。这项研究的结果也可能提供洞察断层滑动在地震期间启动的过程。这项研究将使用长期和密集的被动地震网络获取地震数据，包括已知大型断层附近的高容量废水处理区。数据将用于监测远离活动威尔斯井的压力传播的地震或抗震性质，并探测局部断层的地震响应性。45个宽频带地震仪将以大约5公里的间距在两个为期18个月的部署中部署，首先在俄克拉荷马州，随后在一个活跃流体注入的补充区域。在第一次部署的空间范围内，将在活跃的地震活动上部署一个高密度阵列。具体而言，研究将解决1）密集阵列是否能够通过检测流体压力迁移的信号来连续映射远离废水处理威尔斯的压力迁移前沿; 2）这种迁移沿着断层/裂缝的狭窄路径集中的程度，或分散在多个路径上的程度; 3）大断层带是否对附近较大的地震具有地震反应性;（4）震源特征是否随流体压力的增加而随时间变化。位于俄克拉荷马州中北部的区域包括活跃的地震活动、大型处置威尔斯井和主要断层系统。在第二个区域，与对比的地质环境，本研究将测试和完善的方法来检测信号的高流体压力接近断层。两次部署的结果将在全球诱发地震活动的背景下加以综合。这项研究旨在让当地居民参与进来，帮助他们更有信心找到必要的信息，以便在生活中做出重要的明智决定。科学成果将在经常更新的其他小组完成的研究综合报告的范围内传达给利益攸关方。这项工作将使下一代领导人参与地球科学和工程领域的灾害和资源。