Seismic expression of miocene carbonate platform and reservoir characterization through geophysical approach: application in central Luconia, offshore Malaysia

Abstract

A substantial proportion of proven oil and gas reserves of the world is contained in the carbonate reservoir. It is estimated that about 60% of the world’s oil and 40% of gas reserves are confined in carbonate reservoirs. Exploration and development of hydrocarbons in carbonate reservoirs are much more challenging due to poor seismic imaging and reservoir heterogeneity caused by diagenetic changes. Evaluation of carbonate reservoirs has been a high priority for researchers and geoscientists working in the petroleum industry mainly due to the challenges presented by these highly heterogeneous reservoir rocks. It is essential for geoscientists, petrophysicists, and engineers to work together from initial phases of exploration and delineation of the pool through mature stages of production, to extract as much information as possible to produce maximum hydrocarbons from the field for the commercial viability of the project. In the absence of the well-log data, the properties are inferred from the inversion of seismic data alone. In oil and gas exploration and production industries, seismic inversion is proven as a tool for tracing the subsurface reservoir facies and their fluid contents. In this paper, seismic inversion demonstrates the understanding of lithology and includes the full band of frequency in our initial model to incorporate the detailed study about the basin for prospect evaluation. 3D seismic data along with the geological & petrophysical information and electrologs acquired from drilled wells are used for interpretation and inversion of seismic data to understand the reservoir geometry and facies variation including the distribution of intervening tight layers within the Miocene carbonate reservoir in the study area of Central Luconia. The out-come of the seismic post-stack inversion technique shows a better subsurface lithofacies and fluid distribution for delineation and detailed study of the reservoir.

Reservoir quality and facies modeling of the early Eocene carbonate stratigraphic unit of the Middle Indus Basin, Pakistan

“…Of the sedimentary rocks, carbonate (limestone and dolomite) holds more than 50%-60% of the conventional oil and gas reservoirs in the sedimentary basins of the world (Rohel, 1985;Kargarpour, 2020;Bashir et al, 2021). However, predicting reservoir quality at an inter-well scale (Lai, 2019), identifying high-permeability zones with high porosity (Choquette and pray, 1970;Bohnsak, 2020), and preparing welldefined reservoir characteristics within petrophysical parameters (Nelson 2001;Lucia 2007) are among the major issues associated with carbonate reservoirs (Kelleys and Wallis 1991).…”

“…However, predicting reservoir quality at an inter-well scale (Lai, 2019), identifying high-permeability zones with high porosity (Choquette and pray, 1970;Bohnsak, 2020), and preparing welldefined reservoir characteristics within petrophysical parameters (Nelson 2001;Lucia 2007) are among the major issues associated with carbonate reservoirs (Kelleys and Wallis 1991). Petrophysical analysis of carbonates is a challenging task: different techniques have been used to determine their petrophysical characteristics (Wang et al, 2016;Bashir et al, 2021;Salifou et al, 2021;Aboubacar et al, 2022). Porosity and permeability are the primary petrophysical parameters that define the reservoir characteristics of sedimentary rock.…”

Geomechanical assessment of the Lower Turonian AR-F limestone Member, Abu Gharadig Field, Egypt: Implications for unconventional resource development

“…Similar resources have also been reported from the Ordovician carbonates of the Ordos and Tarim basins of China (Wei et al, 2017;Chen et al, 2020). Recent studies have also focused on such potential tight carbonates from various parts of the world including offshore Malaysia (Bashir et al, 2021), Pakistan (Ali et al, 2022;Ullah et al, 2022), and China (Jiang et al, 2022). Three recent works by Boutaleb et al (2021), Radwan et al (2021) and Fea et al (2022) reported selfsourcing and self-storing unconventional carbonate intervals from the African continent.…”

Depositional environment and diagenesis of early Miocene Nyalau Formation, Sarawak, Malaysia

“…Therefore, combining sedimentology and diagenesis can help us to understand the diagenetic changes in the exposed rock. The study area, Bintulu, is situated in the NW Sarawak (Hutchison, 1996;Liechti et al, 1960;Bashir et al, 2021). The exposed Nyalau Formation is mainly composed of sandstone, clays, lignite and shales (Madon et al, 2007).…”