CAREER: Fluid-driven Deformation in Underground Salt Caverns and Wastewater Injection Sites

职业：地下盐穴和废水注入场的流体驱动变形

• 批准号: 2045983
• 负责人: Patricia Persaud
• 金额: $ 58.91万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2045983&HistoricalAwards=false
• 关键词: CAREER; Fluid; driven; Deformation; Underground; CAREER; Fluid; driven; Deformation; Underground

Earthquakes caused by human activities - such as wastewater injection, geothermal extraction, and underground carbon storage - tend to be small. With notable exceptions, such as the 2016 Pawnee Oklahoma earthquake, these earthquakes often hide below cultural seismic noise. This presents a challenge for both monitoring and detecting them. It impedes studying their causes and assessing corresponding hazards. In the U.S., regions that have been free of earthquakes are now pressed to find reliable ways to address earthquake risks. Research on induced seismicity has expanded in the last decade; but studies have mostly focused on known hotspots in Arkansas, Colorado, Kansas, Ohio, Oklahoma, Texas, and Wyoming. Yet, it is expected that induced earthquakes will occur in regions which did not face this threat before. It is, thus, critical to monitor and catalog the natural baseline seismicity in these regions before induced earthquakes happen; this allows detecting when seismicity rises above background levels and assessing the risks. One such location is the State of Louisiana. It is currently at the threshold of implementing CO2 storage and increased oil and gas exploration. However, Louisiana lacks a statewide seismic network and monitoring program to assess seismic hazards. Here, the researchers integrate research and education in the aim to understand human-driven changes in Louisiana. Deploying geophysical and seismic instruments, they study three key locations related to human activities and resources. These locations are: 1) in northwest Louisiana, a region with high wastewater injection rates; 2) an underground storage cavern, where ground motions have been reported and nearby sinkhole formation has occurred (with precursor earthquake activity); 3) across the Baton Rouge fault that also acts as a patchy barrier for salt water. Integrating multiple data types, the team gradually unveils the new threats Louisiana is facing. The project also provides support to an early-career female scientist, one postdoctoral researcher, and graduate and undergraduate students. It includes the establishment of student-focused regional workshops, notably on Machine Learning applications in Geophysics. The project also fosters broadening participation in science, e.g., by involving students from the Southern University at Baton Rouge, a Historically Black University. This project is jointly funded by the Geophysics Program and the Established Program to Stimulate Competitive Research (EPSCoR).The project is an integrated geophysical study of multiple data types. It produces a detailed characterization of fluid-involved crustal deformation. The results have important societal implications for energy corridors undergoing rapid human change. They characterize the largely unknown deformation of the subsurface beneath a region that supplies a major part of the U.S. oil and gas. This region is challenged by ongoing subsidence, groundwater salinization, and increasing seismicity associated with wastewater disposal from hydrocarbon exploration. The seismic arrays installed at three key locations not only measure the levels of seismicity, but also constrain the poorly understood aseismic deformation. Indeed, innovative techniques are applied, such as Fracture Seismic imaging, that image fluid-filled networks by using harmonic resonances within fractures. Seismological methods are integrated with GPS data analysis to understand the deformation budget of the crust. This approach provides insight into the pattern of crustal deformation driven by human activities. One expected outcome is the first high-resolution mapping of fracture geometry and connectivity, subsurface material properties, and seismic and aseismic deformation in the region. The study, thus, has far-reaching impacts on our general understanding of fluid-driven processes and their effects on crustal deformation.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.

由人类活动引起的地震，例如注入废水，地热提取和地下碳储存 - 往往很小。除了明显的例外，例如2016年波尼俄克拉荷马州地震，这些地震通常藏在文化地震噪音之下。这对监视和检测它们提出了挑战。它阻碍了研究其原因并评估相应的危害。在美国，现在一直迫使没有地震的地区找到可靠的方法来解决地震风险。在过去的十年中，对诱导地震性的研究有所扩大。但是研究主要集中在阿肯色州，科罗拉多州，堪萨斯州，俄亥俄州，俄克拉荷马州，德克萨斯州和怀俄明州的已知热点。然而，预计诱发的地震将发生在以前没有面对这种威胁的地区。因此，在诱发地震发生之前，监测和分类这些区域的自然基线地震性至关重要。这允许检测何时地震高于背景水平并评估风险。这样的位置就是路易斯安那州。目前，它处于实施二氧化碳储存以及石油和天然气勘探增加的门槛。但是，路易斯安那州缺乏全州的地震网络和监测计划来评估地震危害。在这里，研究人员将研究和教育整合起来，目的是了解路易斯安那州以人为驱动的变化。部署地球物理和地震仪器，他们研究了与人类活动和资源有关的三个关键位置。这些位置是：1）在路易斯安那州西北部，一个地区的废水注射率很高； 2）地下储物洞穴，报告了地面运动并发生了附近的污水孔形成（前体的地震活动）； 3）穿过警棍的断层，也充当了盐水的斑点障碍。整合多种数据类型，团队逐渐推出了路易斯安那州面临的新威胁。该项目还为早期职业女科学家，一名博士后研究员以及研究生和本科生提供了支持。它包括建立以学生为中心的区域研讨会，特别是在地球物理中的机器学习应用程序上。该项目还通过参与历史悠久的黑人大学巴吞鲁日（Baton Rouge）的学生参与，促进了扩大科学的参与。该项目由地球物理学计划和刺激竞争研究（EPSCOR）的既定计划共同资助。该项目是多种数据类型的综合地球物理研究。它产生了流体涉及的地壳变形的详细表征。结果对经历人类快速变化的能源走廊具有重要的社会意义。它们表征了在供应美国石油和天然气大部分地区的地下的未知变形。该区域受到持续的沉降，地下水的盐水和与碳氢化合物勘探的废水处置相关的地震性的挑战。安装在三个关键位置的地震阵列不仅衡量地震含量的水平，而且还限制了较熟悉的亚西抗性变形。实际上，应用创新技术，例如断裂地震成像，这些技术通过裂缝内使用谐波共振来形象填充流体的网络。地震方法与GPS数据分析集成在一起，以了解地壳的变形预算。这种方法提供了对人类活动驱动的地壳变形模式的见解。 一个预期的结果是该地区断裂几何和连通性，地下材料特性以及地震和无性变形的第一个高分辨率映射。因此，这项研究对我们对流体驱动过程的一般理解及其对地壳变形的影响具有深远的影响。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的评估来审查标准的评估值得支持的。