System and method for predicting fluid flow characteristics within fractured subsurface reservoirs

摘要

A system and method having application notably towards predicting fluid flow characteristics within fractured subsurface reservoirs. The system and method include steps of reservoir characterization, gridding, discretization, and simulation of geologically realistic models describing the fractured subsurface reservoirs. A stochastic fracture representation that explicitly represents a network of fractures within a subsurface reservoir is constructed and used to build a fine-scale geological model. The model is then gridded such that the network of fractures is represented by interfaces between the fine-scale cells. The model is the discretized and simulated. Simulation can be on a fine-scale or on an upscaled coarse-scale to produce efficient and reliable prediction of fluid flow characteristics within the subsurface reservoir.

主权项

1. A computer-implemented method to predict fluid flow characteristics within a fractured subsurface reservoir, the method comprising:
providing geological data describing a subsurface reservoir having a network of fractures and a rock matrix; generating a stochastic fracture representation that represents the network of fractures; constructing a fine-scale geological model of the subsurface reservoir using the geological data; constructing a fine-scale grid associated with the fine-scale geological model and the stochastic fracture representation, the fine-scale grid being constructed by:
constructing a uniform, structured lattice comprising a plurality of polyhedral cells representing the rock matrix, the polyhedral cells having cell-to-cell interfaces in between the polyhedral cells;refining a portion of the polyhedral cells representing the rock matrix of the uniform, structured lattice, wherein the polyhedral cells being refined are in vicinity of the network of fractures, and wherein refining occurs after constructing;selecting, for each of the fractures, a plurality of the cell-to-cell interfaces in between the polyhedral cells representing the rock matrix and that are adjacent to the fracture to form a continuous interfaces path approximating a geometry of the fracture, wherein selecting occurs after refining; andassociating each of the continuous interfaces paths formed with predetermined fracture properties, wherein associating occurs after selecting;wherein the fine-scale grid that is constructed comprises each of the continuous interfaces paths associated with the predetermined fracture properties; and discretizing the fine-scale grid to compute fine-scale simulation parameters; and simulating the fine-scale simulation parameters to predict fluid flow characteristics within the subsurface reservoir.