Elevating Reservoir Performance in Mature Assets Through Strategic Memory Perforation Execution for Optimization

The Malay basin located offshore Terengganu, Malaysia, is a prolific hydrocarbon-producing region with the very first exploration well drilled in 1969. Since then, numerous fields have been discovered and developed. Thinly bedded and laminated sandstone have been recognized as a significant theme of clastic reservoirs in the Malay basin that may contain substantial hydrocarbon accumulations. Commingled completion strategies are commonly employed to optimize well configurations, combining zones of high-quality reservoirs with those of lower-quality laminated sands. This approach while simplifying well design, inadvertently causes ‘preferential fluid movement’. As a result, hydrocarbons tend to migrate through the higher permeability zones of the superior quality reservoirs, leaving behind ‘bypassed’ hydrocarbon in the lower permeability zones of the laminated sandstones. Without targeted mitigation, this practice leads to generally suboptimal development and depletion plans for laminated sand. Recent infill drilling programs observed the presence of bypassed and unswept hydrocarbons in laminated sandstone, even in fields with over 30 years of production history. Oil in high-quality, homogeneous reservoirs typically exhibits complete or near-complete sweep due to excellent lateral and vertical permeability. In contrast, oil in sand-shale laminated formations tends to be preferentially swept, highlighting the need for strategic well placement to ensure optimal resource extraction. Application of memory perforation, particularly in the context of oil and gas operations, is a cost-effective technique often applied in mature assets to enhance production and achieve higher returns. Despite its advantages, there are several challenges to be addressed to improve the effectiveness of the execution and minimize potential failure. These challenges include: