Geologic and Environmental Systems Directorate, National Energy Technology Laboratory, Department of Energy, 626 Cochran Mill Rd, Pittsburgh, PA, 15236, USA; Leidos Research Support Team, National Energy Technology Laboratory, Pittsburgh, PA, 15236, USA.
Geologic and Environmental Systems Directorate, National Energy Technology Laboratory, Department of Energy, 626 Cochran Mill Rd, Pittsburgh, PA, 15236, USA; Leidos Research Support Team, National Energy Technology Laboratory, Pittsburgh, PA, 15236, USA.
J Environ Manage. 2021 Feb 15;280:111856. doi: 10.1016/j.jenvman.2020.111856. Epub 2020 Dec 25.
Hundreds of oil wells were drilled along Oil Creek in Pennsylvania in the mid-1800s, birthing the modern oil industry. No longer in operation, many wells are now classified as abandoned, and, due to their age, their locations are either unknown or inaccurately recorded. These historic well sites present environmental, safety, and economic concerns in the form of possible methane leaks and physical hazards.
Airborne magnetic and LiDAR surveys were conducted in the Pioneer Run watershed in Oil Creek State Park to find abandoned wells in a historically significant but physically challenging location. Wells were drilled in this area prior to modern geolocation and legal documentation. Although a large number of old wells were abandoned summarily without remediation of the site, much of the land area within Oil Creek State Park is now covered in trees and dense underbrush, which can obscure wellheads. The thick vegetation and steep terrain limited the possibility of ground-based surveys to easily find well sites for methane emissions studies. The data from remote sensing surveys were used to corroborate potential well locations from historic maps and photographs. Potential well sites were verified in a ground-based field survey and monitored for methane emissions.
Two historic photographs documenting oil activity in the late 1800s were georeferenced using a combination of magnetic and LiDAR data. LiDAR data, which were more useful in georeferencing and in field verification, identified 290 field locations in the Pioneer Run watershed, 86% of which were possible well sites. Sixty-two percent of the ground-verified wells remained unplugged and comprised the majority of leaking wells. The mean methane emissions factor for unplugged wells was 0.027 ± 0.099 kg/day, lower than other Appalachian Basin methane emissions estimates.
LiDAR was used for the first time, in combination with an airborne magnetic survey, to reveal underground oil industry features and inform well identification and remediation efforts in difficult-to-navigate regions. In the oldest oil fields, where well casing has been removed or wood conductor casing was installed, historic photographs provide additional lines of evidence for oil wells where ground disturbances have concealed surface features. Identification of well sites is necessary for mitigation efforts, as unplugged wells emit methane, a potent greenhouse gas.
19 世纪中期，宾夕法尼亚州的 Oil Creek 沿线钻了数百口油井，孕育了现代石油工业。许多油井现已废弃，不再运营，由于年代久远，其位置或未知或记录不准确。这些具有历史意义的油井遗址以可能的甲烷泄漏和物理危害的形式带来了环境、安全和经济方面的问题。
在 Oil Creek 州立公园的 Pioneer Run 流域进行了航空磁测和 LiDAR 调查，以在一个具有历史意义但具有挑战性的地点寻找废弃油井。该地区在现代地理位置和法律文件之前就已经钻了大量旧油井。尽管许多旧油井未经修复就被随意废弃，但 Oil Creek 州立公园的大部分土地现在都被树木和茂密的灌木丛覆盖，这可能会掩盖油井井口。茂密的植被和陡峭的地形限制了地面调查找到用于甲烷排放研究的油井位置的可能性。遥感调查的数据用于从历史地图和照片中佐证潜在的油井位置。在地面实地调查中对潜在的油井位置进行了核实，并监测了甲烷排放情况。
两张记录 19 世纪后期石油活动的历史照片通过结合使用磁测和 LiDAR 数据进行了地理参考。LiDAR 数据在地理参考和实地验证方面更为有用，它在 Pioneer Run 流域确定了 290 个野外位置，其中 86%可能是油井位置。在地面核实的油井中，有 62%未被封堵，占泄漏油井的大多数。未封堵油井的平均甲烷排放因子为 0.027±0.099kg/天，低于阿巴拉契亚盆地的其他甲烷排放估计值。
首次结合航空磁测使用 LiDAR 揭示了地下石油工业特征，并为难以进入的地区的油井识别和修复工作提供了信息。在最古老的油田，油井套管已被移除或安装了木质导体套管，历史照片为地面特征被掩盖的油井提供了额外的证据。确定油井位置对于缓解措施是必要的，因为未封堵的油井会排放甲烷，这是一种强大的温室气体。
