Two purpose-built monitoring wells monitoring wells at the Cranfield Field Phase III CO₂ Storage Project were studied in detail using time-lapse well integrity logging, cased-hole sidewall core sampling, and point pressure testing to study the effect of CO₂ on the materials used to construct wells for carbon capture, utilization, and storage (CCUS) projects. The wells were constructed using conventional steel casing, fiberglass casing, and conventional well cements. Both wells were heavily outfitted with monitoring equipment in the annulus between the formation and casing. The time-lapse comparison of the well integrity logs showed a general degradation of signal in many places along the well. Laboratory analyses of the sidewall cores showed that CO₂ affected the cement in the well at every point that was cored, with significant alteration occurring adjacent to one of the monitoring control lines collected as part of a core. Additionally, the time-lapse logs and sidewall cores showed the fiberglass casing was strongly affected in the CO₂ reservoir, causing the inside diameter of the casing to decrease. This study provides insight into how decisions regarding well materials and monitoring technology can impact well integrity over a period as short as 6 years.

两个专用的监测井在克兰菲尔德场三期CO监测井₂封存项目详细使用时间推移以及完整性测井，套管井井壁岩心取样，并指向压力测试，以研究CO的效果进行了研究₂对用于建造碳捕集，利用和封存（CCUS）项目的油井的材料。这些井是使用常规钢套管，玻璃纤维套管和常规井水泥建造的。两口井在地层和套管之间的环空均配备了监控设备。井完整性测井的时移比较显示，沿井许多地方的信号普遍下降。侧壁芯的实验室分析表明，CO ₂在每个取芯的位置都影响了井中的水泥，在作为取芯的一部分的监测控制管线之一附近发生了重大变化。此外，随时间推移的测井曲线和侧壁岩心显示，玻璃纤维套管在CO ₂储层中受到强烈影响，导致套管的内径减小。这项研究深入了解了有关油井材料和监测技术的决策如何在短短6年内如何影响油井完整性的问题。