密封缺陷和流体诱导的地震性
Zahra Esmaeilzadeh1, David W Eaton1, Navid Hosseini2
1Department of Earth, Energy & Environment, University of Calgary , Calgary, Alberta, Canada.
概括
密封缺陷,阻碍流体流动的障碍,与水力压裂 (HF) 过程中诱导的地震性相关. 这项研究揭示了它们在地下压力变化和地震风险中的作用,影响了二氧化碳储存潜力.
科学领域:
- 地质物理学 地质物理学
- 表面下流体动力学 表面下流体动力学
- 构造物理学 构造物理学
背景情况:
- 密封断层作为不透的障碍物,定义了地下孔隙压力领域.
- 这些断层对于碳化合物陷和在耗尽的水库中潜在的二氧化碳储存至关重要.
- 以前的假设表明密封断层仅仅是压力的隔间,但这项研究探讨了它们的动态行为.
研究的目的:
- 研究水力压裂 (HF) 过程中密封缺陷和诱导的地震性之间的关系.
- 了解密封断层在毛孔压力分隔和地震风险中的作用.
- 用数值模拟分析高频应力下的密封故障的行为.
主要方法:
- 诱导地震性分布的统计分析与孔隙压力梯度的关系.
- 解释高孔压梯度区域作为密封断层系统.
- 使用速率和状态摩擦力学,对断层交叉的液压压裂的数值模拟.
主要成果:
- 在HF期间诱导的地震性显示出与高侧孔压梯度具有显著的空间相关性,被解释为密封断层.
- 最大的地震事件,4.5ML的主震,发生在两个井之间,孔隙压力差异很大 (~10MPa).
- 断层破裂的数值模拟与HF井附近观察到的冲击滑动断层相一致.
结论:
- 密封断层表现出以前未知的行为,影响诱导的地震性.
- 了解这些断层行为对于评估和减轻与地下活动相关的地震风险至关重要.
- 这些发现对二氧化碳储存和资源提取在低透性储中的完整性有影响.
相关概念视频
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01:27Movement Joints in Buildings
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01:23Plane Potential Flows
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01:28Types of Non-structural Cracks in Concrete
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01:26Unsoundness of Aggregate due to Volume Change
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