Sweet Spot Geological Techniques for Detecting Oil Field Exploration Locations

Abstract

AbstractA significant challenge for the hydrocarbon industry at the beginning of the current century was related to geologically high-risk oil and gas reservoirs. This led a new generation of geoscientists to focus on three important areas: mature fields, deep water, and unconventional reservoirs. Fortunately, several technological drilling and software innovations have helped further the understanding of global petroleum systems. This paper discusses a case history in which geological integration was performed by a diverse group of geoscientists of varying disciplines, whereby the introduction of integrated geological techniques using computer systems allowed a better conceptualization of reservoir behavior, helping to reduce analysis time. The integrated method uses TIER quantification, which allows enhanced visualization for specialists to identify potential hydrocarbon zones and volumes in the reservoir. This involves generating a two-dimensional (2D) sweet-spot map that is overlaid on petrophysical maps to show the distribution of principal reservoir properties (e.g., effective porosity, hydrocarbon content, pore volume, permeability, sand volume, etc.). Petrophysical evaluation curves are used to calculate a three-dimensional (3D) sweet-spot log using a computer program, which facilitates modeling of the heterogeneity and depth range of the reservoir. It is possible to populate the 3D sweet-spot distribution into a geocellular model. The integration of the sweet-spot distribution, seismic attributes, historical oil production, and petroleum system studies allows for better determination of possible hydrocarbon reservoirs. This helps reduce uncertainty related to potential geological exploration opportunities. The original oil-in-place (OOIP) can be calculated using 3D geocells conforming to arrangements of simulation layers. The static geocellular model then undergoes scaling, which is transferred to a numerical simulator.This methodology has been applied in the tight-oil sand reservoir of the Chicontepec channel in Mexico, which is composed of a high stratigraphic element having a concentrated trend of productive Upper Paleocene sands. The structural fault model was not severely affected in the area of interest; therefore, it can be used as a reliable geological model to simplify the integration of sweet-spot distribution for prospective sand intervals.