Fault and top seals thematic collection: a perspective

Abstract

Predicting the sealing capacity of faults and caprocks has been a long-standing uncertainty for those involved in the exploration, appraisal and development of petroleum reservoirs. In more recent years, interest in the topic has increased in a wide range of other applications, particularly those related to the decarbonization of our energy supply such as carbon capture and storage (CCS), radioactive waste disposal, geothermal energy production and underground energy storage (e.g. compressed air, hydrogen). Knowledge of how faults impact fluid flow is also important for management of drinking water supplies. To communicate new advances in research in these areas, the EAGE organized the first international conference on Fault and Top Seals in 2003. These conferences have continued to be held at roughly 4 yearly intervals and have brought together scientists from a wide range of disciplines to discuss new research findings and workflows relevant to predicting fault and top seal behaviour, as well as presenting case studies covering both successful and unsuccessful attempts to predict sealing capacity.Thematic collection: This article is part of the Fault and top seals collection available at: https://www.lyellcollection.org/cc/fault-and-top-seals-2019

The quantitative evaluation of fault sealing during the Cenozoic in Gaoyou Depression, Subei Basin

“…The essence of fault sealing in sedimentary basins refers to differential displacement pressure between fault rocks and reservoirs (Fisher et al, 2021; Lv et al, 2021; Lv & Wang, 2010; Pei et al, 2015). Commonly, the displacement pressure in fault rocks exceeds greater than that in the reservoirs (Figure 3).…”

“…Commonly, the displacement pressure in fault rocks exceeds greater than that in the reservoirs (Figure 3). The displacement pressure of fault rocks depends largely on mud content and compaction and diagenesis of fault rocks (Fisher et al, 2021; Qu et al, 2021; Reilly, Nicol, Walsh, & Kroeger, 2016; Wang et al, 2016; Wang & Dai, 2012). The conditions for generating differential displacement pressure include as follows: (1) contact between reservoirs on one fault wall and non‐reservoirs on the other fault wall; (2) displacement pressure of matrix greater than that of the reservoir.…”

“…The juxtaposition seal refers to lithological contact between reservoir (sandstone) and regional seal (mudstone) resulting from fault dislocation (Fisher et al, 2021; Fu & Xia, 2013; Pei et al, 2015; Zhang, 2020). The oil–water interface of reservoirs with juxtaposition seal, is controlled by thickness of the regional seal or spill point (Fu, Li, Lv, He, & Lu, 2011).…”

“…Fault sealing has long been of great scientific interests to both scholars and oil industry since the proposal that came from the AAPG annual meeting in 1955 (Weeks, 1958). The scholars and oil industry started to pay increasing attention to fault sealing in controlling hydrocarbon migration and reservoir formation (Chen, Xiao, Xia, & Huang, 2006; Fisher, Schaefer, Kaminskaite, Dewhurst, & Yielding, 2021; Fu, Yang, Lv, & Shi, 2013; He et al, 2021; Li, Wu, Huang, Wang, & Li, 2020; Liu, Liu, Li, Wang, & Chen, 2002; Pei et al, 2015). However, how to evaluate fault sealing capability (especially lateral fault seal capability) in hydrocarbon migration and reservoir formation still remains unclear.…”

“…In recent years, scholars and the oil industry wonder whether it is determined by opening or closing of the faults whether a fault acts as pathway or seal (Fu et al, 2013; Jiang, Zhao, & Hu, 2021; Jing et al, 2021; Lei et al, 2019; Lv et al, 2016). It commonly employs two extremely limiting conditions (opening or closing) to describe and characterize faults (Fisher et al, 2021; Pei et al, 2015). Actually, there are more than two extremely limiting conditions than that, such as transition conditions between opening and closing in most circumstances.…”