Abstract：
Increasing seismic activity due to fluid injections for oil and gas production may be contributing to leakage along non-producing oil and gas wells and emitting methane, a potent greenhouse gas. However, the extent to which nearby seismicity may drive or exacerbate methane emissions and cause well integrity issues is unknown. Therefore, we analyze field evaluations at 448 non-producing oil and gas wells in Northeast British Columbia (NEBC) and geospatially analyze oil and gas well and fluid injection data alongside locations of 3515 earthquakes from 2001 to 2021 and 130 faults. Through analysis of ground and helicopter-based field evaluations of non-producing wells in NEBC, we show that methane emission rates of non-producing wells average at 8301 mg/h/well but vary by 10 orders of magnitude. We find that higher methane emission rates (milligrams of methane/h/well) are observed at wells with larger flowing pressures at the wellhead during completion (kPa) and with shorter distances (m) to earthquakes, particularly at plugged wells. These results imply that seismicity may increase the likelihood of non-producing well integrity issues and methane leakage, thereby also exacerbating groundwater contamination and environmental degradation risks.
摘要：
由于用于石油和天然气生产的流体注入而导致的地震活动增加，可能会导致沿非生产油气井的泄漏并排放甲烷，一种强效的温室气体.然而,附近的地震活动可能驱动或加剧甲烷排放并导致油井完整性问题的程度尚不清楚。因此,我们分析了不列颠哥伦比亚省东北部（NEBC）448口非生产油气井的现场评估，并对2001年至2021年的3515次地震和130个断层的位置进行了地理空间分析油气井和流体注入数据。通过分析NEBC非生产井的地面和直升机现场评价，我们表明，非生产井的甲烷排放速率平均为8301mg/h/井，但变化幅度为10个数量级。我们发现，在完井期间（kPa）和距地震的距离（m）较短的井口流动压力较大的井中，观察到较高的甲烷排放率（甲烷毫克/小时/井）。特别是在堵塞的井。这些结果表明，地震活动可能会增加非生产井完整性问题和甲烷泄漏的可能性，从而也加剧了地下水污染和环境退化的风险。
