Induced earthquake source process imaging and groundwater chemistry monitoring in the Western Canada sedimentary basin

加拿大西部沉积盆地诱发地震震源过程成像和地下水化学监测

• 批准号: 494141-2016
• 负责人: Liu, Yajing
• 金额: $ 11.19万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Strategic Projects - Group
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=693863
• 关键词: Induced; earthquake; source; process; imaging

In the past 5 years, there has been a drastic increase in the number of earthquakes potentially induced by fluid injection during unconventional oil and gas extraction in North America, including previously seismically quiescent areas. In particular, the occurrences of magnitude 4 and greater earthquakes associated with hydraulic fracturing operations in northeast British Columbia and Alberta has led to temporarily shut-down of well production and caused safety concerns among local communities. Despite the densification of seismic monitoring network, the detailed source process and triggering threshold of injection induced earthquakes remains a critical challenge to seismic hazard assessment and mitigation. In this project, we proposed to incorporate innovative geophysical, hydrogeological and geochemical monitoring techniques and numerical tools, to quantitatively image and model induced seismicity source processes at two hydraulic fracturing wells and one disposal well in northeast BC and west Alberta. At each target site, we will install a dense array composed of broadband seismometers and integrated seismo-geodetic systems for recording seismographs of induced earthquakes, and angled reflectors for enhanced Interferometry Satellite Aperture Radar ground motion imaging. We will also conduct groundwater chemistry and isotope surveys at the target sites, in order to identify temporal variations related to fluid injection with a focus on potential earthquake precursory signals. Field observations will be used to constrain the poroelastic model for simulating fluid pressure and solid matrix stress changes due to injection, and for designing injection strategies that reduce the likelihood of triggered seismic slip on pre-existing faults. The outcome of this project will provide unbiased scientific knowledge for the public policy making by our supporting organization GSC as well as regulatory policy adjustment by provincial oil and gas commissions.

在过去的5年中，在北美非常规石油和天然气提取期间，包括以前的地震静止区域在非常规石油和天然气提取过程中，液体注入可能引起的地震数量急剧增加。特别是，与不列颠哥伦比亚省东北部和艾伯塔省的液压压裂行动相关的4级和更大地震的发生导致暂时关闭了生产井，并引起了当地社区的安全问题。尽管地震监测网络致密，但详细的源过程和触发注射诱发地震阈值仍然是对地震危害评估和缓解措施的关键挑战。在这个项目中，我们提议将创新的地球物理，水文地质和地球化学监测技术和数值工具纳入，以定量图像和模型引起的地震源过程在两个液压压裂井中，并在东北艾伯塔省东北部和西艾伯塔省有一个井口。在每个目标部位，我们将安装一个密集的阵列，该阵列由宽带地震仪和集成的地震地理系统组成，用于记录诱导地震的地震仪以及增强干涉卫星孔径雷达雷达接地运动成像的倾斜反射器。我们还将在目标部位进行地下水化学和同位素调查，以识别与流体注入相关的时间变化，重点是潜在的地震前体信号。现场观察将用于约束毛弹性模型，以模拟注射导致的流体压力和实心基质应力变化，并设计降低预先存在故障触发地震滑移的可能性的注入策略。该项目的结果将为我们的支持组织GSC的公共政策制定以及省级石油和天然气委员会的监管政策调整提供公正的科学知识。