Evaluation and Understanding the Potential of Enhanced Oil Recovery for a Candidate Offshore Sandstone Field

Abstract

The aim of this investigation is to develop a comprehensive understanding of an enhanced oil recovery (EOR) candidate reservoir based in an unconventional sandstone dominated environment. The unique geology, owing to its proximity to an inland, endorheic basin, alongside its complex stratigraphic geometry incorporating extensive folding and faulting as well as a laterally extensive unconformity. The study leans heavily on the forefront of reservoir characterizations. Reservoir characterization is crucial in providing an outline of the sub-surface and helps visualize the hydrocarbon system in-place. Our study area is the deeper consolidated units. This section was analyzed in detail to understand the petrophysical and fluid properties. The properties of the rock formation(s) of interest were identified from mineralogical content based on XRD analysis and SEM analysis to develop an interlink between the results. A compilation of the results plays a key role in determining reservoir quality and fluid properties which heavily influences important variables such as porosity, permeability, capillary pressure, relative permeability, wettability, interfacial tension, and fluid compositions. The clay mineralogy affects the penetration rate and the diagenetic overprint either enhances or deliberates fluid flow. The novelty of this integrated study lays the foundation for a thorough and bespoke screening EOR study, which is currently under development for an offshore candidate field. Preliminary screenings were also conducted through core flooding with representative outcrops. An understanding of the integration of the various reservoirs and fluid properties is essential in determining the characteristics of the entirety of the candidate reservoir. Incorporating these complex zones in an integrated reservoir characterization study is fundamental in achieving successful EOR deployment and optimizes oil production.

Experimental Investigation of a Self-adaptive Thickening Polymer Performance under High-Temperature–High-Salinity Reservoir Conditions

“…The geological background and reservoir characterization of the targeted field have been well summarized by Qi et al 18 and Rabbani et al 19 Based on field data, representative core plugs cut from Gray Berea sandstone outcrops were chosen for the polymer core-flood experiments. Sixteen core plugs (batch 1) were used for the formation damage test, and 10 core plugs (batch 2) were used for the polymer core-flood oil displacement efficiency study.…”

Rheological properties of polymer solutions and ways to improve the efficiency of development of high-viscosity oil fields in Uzbekistan

“…In recent years, oil fields with complex geological structure have been discovered in many oil and gas bearing regions of the world [1,2]. These fields are characterized by low oil saturated thickness of reservoirs, low filtration-capacity properties of reservoirs, high viscosity of reservoir oil and heterogeneity of productive horizons, etc [3].…”

“…One of the most important issues in increasing the degree of oil recovery from the subsurface is the study of structural and mechanical properties of polymer solutions, their influence on the filtration process in the reservoir and ways to regulate them. At present, a large amount of theoretical and experimental material has been accumulated to study the structural and mechanical properties and flow characteristics of non-Newtonian oils [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Studies have shown that during the development of wells that have opened deposits of heavy high-viscosity oils, there are complications associated with the difficulty of lifting oil to the surface.…”

“…Studies have shown that during the development of wells that have opened deposits of heavy high-viscosity oils, there are complications associated with the difficulty of lifting oil to the surface. The high content of asphaltene-resinous substances causes the manifestation of initial pressure gradients and relaxation processes in the oil-collector system during filtration, large pressure losses in wellhead communications and oil flow rates [1][2][3][4][5], leads to a significant reduction in oil recovery. A characteristic feature of heavy oil producing wells is also a sharp increase in water cut at the initial stage of development.…”