Subsidence associated with oil extraction, measured from time series analysis of Sentinel-1 data: case study of the Patos-Marinza oil field, Albania
Subsidence associated with oil extraction, measured from time series analysis of Sentinel-1 data: case study of the Patos-Marinza oil field, Albania
复制标题
通过 Sentinel-1 数据的时间序列分析测量与石油开采相关的沉降：阿尔巴尼亚 Patos-Marinza 油田的案例研究
DOI：
10.5194/se-11-363-2020
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发表时间：
2019
期刊：
影响因子：
3.4
通讯作者：
R. Koçi
中科院分区：
文献类型：
--
作者：
M. Métois;Mouna Benjelloun;C. Lasserre;R. Grandin;L. Barrier;E. Dushi;R. Koçi
抽象。阿尔巴尼亚中部的帕托斯-马林扎油田（北纬40.71度，东经19.61度）自1939年开始运营，是欧洲最大的陆上油田之一。自2004年以来，Bankers石油有限公司（以下简称Bankers）每年从阿尔巴尼亚亚得里亚海周边凹陷Durres盆地的Messinian砂岩地层中开采700多万桶石油。在这项研究中，我们利用新的哨兵-1雷达图像获得每6至12天以上阿尔巴尼亚测量Myzeqeja平原，特别是在帕托斯-Marinza油田的表面位移。覆盖该区域的两个上升和下降轨迹的图像通过雷达干涉测量（干涉合成孔径雷达）时间序列分析在2014年至2018年的时间跨度进行处理，提供一致的平均视线（LOS）速度图和位移时间序列。区域变形场显示出整个盆地相对于高地的缓慢沉降（速率为2.5 mm/年），我们将其解释为自然和人为压实的结合。这一广泛的情况因一个非常强烈的局部沉降信号而变得复杂，该信号的速率高达15毫米/年，在空间上与帕托斯-马林扎油田相关，在拥有大多数作业威尔斯井的区域最大，在那里使用了强化采油技术。从光学图像上可以看出，最大沉降面积与活动威尔斯井之间存在显著的空间相关性，这有利于石油开采引起的地表变形。这种变形很好地再现了弹性模型模仿盆地和油藏压实使用平面负拉伸（关闭）位错。这种建模提供了对油藏体积收缩率的一阶估计（约0.2 Mm 3/年），并表明在油田的中部进行了同时注入活动，在那里观察到了小的隆起。我们的新的InSAR衍生证据表明，与油田作业有关的重大表面应变提出了这些作业对当地地震活动的潜在影响的问题。自2009年以来，在油田重新启用后不久，似乎观察到附近释放的地震矩速率略有增加。然而，如果不对该地区进行进一步的地震监测和更长的干涉合成孔径雷达时间序列，这个问题将仍然悬而未决。
Abstract. The Patos-Marinza oil field in central Albania (40.71∘ N, 19.61∘ E), operated since 1939, is one of the largest onshore oil fields in Europe. More than 7 million oil barrels are extracted every year from the Messinian sandstone formations of the Durres Basin in the Albanian Peri-Adriatic Depression by the Bankers Petroleum Ltd. (hereafter Bankers), which has been operating the field since 2004. In this study, we take advantage of the new Sentinel-1 radar images acquired every 6 to 12 d over Albania to measure the surface displacement in the Myzeqeja plain and in the Patos-Marinza oil field in particular. Images from two ascending and descending tracks covering the area are processed through a radar interferometry (InSAR) time series analysis over the 2014 to 2018 time span, providing consistent average line-of-sight (LOS) velocity maps and displacement time series. The regional deformation field exhibits a slow subsidence of the entire basin relative to the highlands (at rates of 2.5 mm yr−1) that we interpret as a combination of natural and human-induced compaction. This broad picture is complicated by a very strong local subsidence signal with rates as high as 15 mm yr−1 that spatially correlates with the Patos-Marinza oil field and is maximal in the zone holding most of the operating wells, where enhanced oil recovery techniques are used. The striking spatial correlation between the maximum subsidence area and the active wells, as seen from optical images, argues in favor of surface deformation induced by oil extraction. This deformation is well reproduced by elastic models mimicking the basin and reservoir compaction using planar negative tensile (closing) dislocations. Such modeling provides a first-order estimation of the volumetric deflation rate in the oil reservoir (∼0.2 Mm3 yr−1), and it suggests that concurrent injection activity has been conducted in the central part of the field where small uplift is observed. Our new InSAR-derived evidence of significant surface strain associated with the oil field operations raises the question of the potential impact of these operations on the local seismicity. A slight increase in the nearby released seismic moment rate seems to be observed since 2009, shortly after the oil field reactivation. However, without further seismological monitoring of the area and longer InSAR time series, this question will remain open.