The value of core in mature field development – examples from the UK North Sea

Kelly, Sean, Worden, Richard ORCID: 0000-0002-4686-9428 and Mc Ardle, Peter (2023) The value of core in mature field development – examples from the UK North Sea. Geological Society, London, Special Publications, 527 (1). pp. 261-278.

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Abstract

Core-based studies have had material impacts on the understanding of a number of late-life, mature North Sea Brent Group hydrocarbon reservoirs. These studies have included sedimentological, diagenetic and reservoir quality focused evaluations of core. The primary objective of the studies has been to improve conceptual and qualitative models that can be utilized in reservoir modelling and also for infill drilling and well workover evaluations. Most of these studies have been undertaken on old core samples collected in the 1980s and 1990s. Two case studies are described here that provide examples of the utility of core in mature fields. (1) Heather Field calcite: to quantitatively assess the distribution of calcite cements and their impact on hydrocarbon volumes and reservoir quality distribution in Brent reservoirs. (2) Thistle Field Etive Formation barriers and baffles: to characterise and describe the origin and distribution of low-permeability intervals within the Etive Formation reservoir. These two studies used a wide variety of core-based techniques including core logging and description, optical microscopy and petrographical studies, isotope analyses, XRD and SEM-EDS (QEMSCAN)-based mineralogy, portable-XRF, NDTr and NDT geochemical analysis, as well as image analysis of grain size and texture. These data were then integrated with other subsurface datasets, such as well log, seismic data and well performance data, in order to address the specific reservoir challenge. These new and focussed reappraisals of core demonstrate the dual value of core-based studies, which can: (1) Improve the understanding of producing hydrocarbon reservoirs, leading to improved productivity and recovery. Core is a full asset life-cycle resource and provides critical insight at all stage of field maturity as production behaviour changes and alternative development strategies are considered. (2) Further our general knowledge and understanding of clastic sedimentology and diagenesis using rich and diverse core-based datasets backed up by substantial well log and seismic datasets.

Item Type:	Article
Divisions:	Faculty of Science and Engineering > School of Environmental Sciences
Depositing User:	Symplectic Admin
Date Deposited:	10 Aug 2022 08:47
Last Modified:	27 Mar 2024 13:50
DOI:	10.1144/SP527-2021-20
Related URLs:	Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3160799