Systems, methods, and computer-readable media for continuous capillary pressure estimation

Abstract

Provided are methods, systems, and computer-readable media for determining capillary pressure in a basin / reservoir. Well log data is obtained that includes permeability log data, porosity log data, water saturation log data, and oil saturation log data. Thomeer parameters for a multi-pore system of a Thomeer model are determined by evaluating an objective function that measures the mismatch between the well log data and modeled data having the Thomeer parameters as input. The objective function is iteratively evaluated using linear equality constraints, linear inequality constraints, and nonlinear equality constraints until convergence criteria are met.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]This invention relates generally to sedimentary basin exploration and reservoir hydrocarbon production and, more particularly, to estimating capillary pressure for basin exploration and reservoir development and production.[0003]2. Description of the Related Art[0004]Various exploration and production systems are employed to find and extract oil, natural gas, and other resources from natural basins and reservoirs in the earth. Capillary pressure is a property used for basin exploration and reservoir development and production. For example, capillary pressure may be used to compute the original hydrocarbon in place (OHIP) and to estimate a recovery factor. Reservoir modeling and simulation enables characterization of static reservoir properties and prediction of reservoir dynamic behavior. Exploration and production activities and strategies are strongly impacted by reservoir modeling workflows and techniques. Accordingl...

AI Technical Summary

Benefits of technology

The patent text describes methods and computer code for determining the capillary pressure of a basin or reservoir using well log data. The methods involve accessing well log data, including permeability log data, porosity log data, water saturation log data, and oil saturation log data. The Thomeer parameters, which include a fractional bulk volume, pore geometrical factors, and minimum entry pressure, are determined using a Thomeer model. The objective function includes a linear equation and a non-linear equation. The computer code and methods can be used to improve oil and gas exploration and production in reservoirs.

Problems solved by technology

However, due to the expense and time associated with SCAL procedures, only a relatively few measurements of capillary pressure are typically performed.

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