Joint Inversion of Fracture Model Properties for CO2 Storage Monitoring or Oil Recovery History Matching — For oil recovery or CO2 storage, “reservoirs” are commonly used to designate geological structures where oil can be found or CO2 can be stored. All reservoirs present a heterogeneity in terms of rock type and properties (such as porosity and permeability). In addition, some of these reserv...

Seismic methods play an important role in the development of tight fractured reservoirs with substantial spatial variability of fracture density. Here, we apply a comprehensive processing sequence designed for layered azimuthally anisotropic media to wide-azimuth P-wave data acquired over a fractured gas sand formation in the Rulison field, Colorado. The main processing steps include nonhyperbo...

Field, laboratory, and modeling studies of fractured rock have generated great interest from both fundamental and applied perspectives. Many practical applications of these studies are crucial for the exploitation of petroleum and geothermal reservoirs, the safe environmental management of groundwater, the isolation of radioactive waste in under­ ground repositories, cleanup technologies for ot...

This article presents a method for simulation of continuous and discrete fracture parameters distributions in hydrocarbon reservoirs using Sequential Indicator Simulation (SIS) and Sequential Gaussian Simulation (SGS) methods. Fracture parameters including azimuth, dip and density are integrated with the porosity and permeability values determined in the models. Based on this study we have iden...

This paper proposes a method for quantitative integration of seismic (elastic) anisotropy attributes with reservoir performance data as an aid in characterization of systems of natural fractures in hydrocarbon reservoirs. This method is demonstrated through application to history matching of reservoir performance using synthetic test cases. Discrete Feature Network (DFN) modeling (Dershowitz et...

We have extended our “EKP-postprocessor” (Ishido and Pritchett, 1996) to calculate electrokinetic potentials in fractured geothermal reservoirs that are represented computationally as “MINC” doubleporosity media. In such reservoir descriptions, global mass exchange between adjacent macroscopic computational grid blocks takes place mainly through the “fracture zone”. Inter-block flow through the...

Tight gas reservoirs are characterized by single-phase (gas) or two-phase (gas and liquid) flow in extremely low-permeability, highly heterogeneous porous/fractured, and stress-sensitive rock. Gas flow in such tight formations is further complicated by other co-existing processes, such as Klinkenberg effect, non-Newtonian or non-Darcy flow behavior, due to strong interaction between fluid molec...

Aligned vertical fractures introduce velocity anisotropy which is directly related to parameters, such as fracture density, fracture shape and fracture contents. Effective medium models allow us to study qPand qS-wave velocity anisotropy in rocks with aligned vertical fractures, intersecting fracture sets and aligned fractures with smallscale porosity. Spatially varying fracture density distrib...

In petroleum exploration and production, fractures are one of the most common and important geological structures, for they have a significant effect on reservoir fluid flow. Despite their importance, detection and characterization of natural fractures remains a difficult problem for engineers, geologists and geophysicists. This paper presents a technique for the identification and characteriza...