Determining Parameters of Matrix-Fracture Interface Fluid Transfer from Laboratory Tests

2006 ◽  
Author(s):  
Faruk Civan ◽  
Maurice Lee Rasmussen
Keyword(s):  
Laboratory Tests ◽  
Matrix Fracture ◽  
Fluid Transfer ◽  
Fracture Interface

CO2-Shale Reactivity at the Matrix-Fracture Interface

2019 ◽  
Author(s):  
Sean Sanguinito ◽  
Patricia Cvetic ◽  
Angela Goodman ◽  
Barbara Kutchko ◽  
Sittichai Natesakhawat
Keyword(s):  
Matrix Fracture ◽  
The Matrix ◽  
Fracture Interface

Development of an Embedded Discrete Fracture Model for Multi-Phase Flow in Fractured Reservoir

2014 ◽  
Vol 668-669 ◽  
pp. 1488-1492
Author(s):  
Fang Qi Zhou
Keyword(s):  
Neumann Boundary ◽  
Fracture Model ◽  
Fractured Reservoir ◽  
Discrete Fracture Model ◽  
Matrix Fracture ◽  
Discrete Fracture ◽  
The Matrix ◽  
Multi Phase Flow ◽  
Multi Phase ◽  
Fracture Interface

Considering the discontinuities of the phase saturations and pressure gradients at the matrix-fracture interface, a modified algorithm for the embedded discrete fracture model is proposed. In this algorithm, the exchange rate between fracture and matrix on two sides of the interface are calculated separately. To avoid the problem for defining the physical variables on the matrix grid blocks overlaid by fracture, the Neumann boundary conditions are instead in the calculations of other matrix grid blocks. The numerical examples show that the simulation results of the proposed algorithm agree very well with those of the discrete fracture model. In reservoir with high matrix capillary pressure, the grids must be enough refined in the neighborhood of the matrix-fracture interface to achieve high numerical accuracy.

Matrix-Fracture Interface Cleanup in Unconventional Shale Reservoirs

2015 ◽  
Author(s):  
Tadesse Weldu Teklu ◽  
Najeeb Alharthy ◽  
Waleed Alameri ◽  
Hossein Kazemi ◽  
Ramona M. Graves
Keyword(s):  
Matrix Fracture ◽  
Shale Reservoirs ◽  
Fracture Interface

Imbibition-Dominated Matrix-Fracture Fluid Transfer in Dual Porosity Simulators

1987 ◽  
Author(s):  
B.L. Beckner ◽  
K. Ishimoto ◽  
S. Yamaguchi ◽  
A. Firoozabadi ◽  
K. Aziz
Keyword(s):  
Dual Porosity ◽  
Matrix Fracture ◽  
Fracture Fluid ◽  
Fluid Transfer

Well Pressure Behavior of a Naturally Fractured Reservoir

1983 ◽  
Vol 23 (05) ◽  
pp. 769-780 ◽  
Author(s):  
Tatiana D. Streltsova
Keyword(s):  
Pressure Response ◽  
Transitional Period ◽  
Late Time ◽  
Fractured Reservoir ◽  
Fracture Pressure ◽  
Matrix Fracture ◽  
Naturally Fractured ◽  
The Matrix ◽  
Uniform Medium ◽  
Fluid Transfer

Abstract The pressure response pattern of a naturally fractured reservoir is considered under the assumption allowing matrix-to-fracture crossflow to result from a diffusion mechanism of fluid transfer through the matrix. The transitional pressure during time-variant crossflow is shown to develop on a semilog plot a linear segment with a slope equal to one-half that of the early- and late-time pressure segments. For a single well, this allows use of a conventional Homer-type analysis. Introduction A naturally fractured formation is generally represented by a tight matrix rock broken up by fractures of secondary origin. The fractures are assumed continuous throughout the formation and to represent the paths of principal permeability. The high diffusivity of a fracture results in a rapid permeability. The high diffusivity of a fracture results in a rapid response along the fracture to any pressure change such as that caused by well production. The rock matrix, having a lower permeability but a relatively higher primary porosity, has a "delayed" response to pressure changes that occur in the surrounding fractures. Such nonconcurrent responses cause pressure depletion of the fracture relative to the matrix, which in turn induces matrix-to-fracture crossflow. This period of transient crossflow takes place immediately after the fracture pressure response and before the matrix and the fracture pressures equilibrate, after which the formation acts as a uniform medium with composite properties. The effect of assumptions made on the nature of matrix and properties. The effect of assumptions made on the nature of matrix and fracture interaction is manifested during this transitional period of matrix-to-fracture fluid transfer. The flux of fluid released by the matrix depends on the matrix size, porosity, permeability, and the matrix/fracture pressure difference. At the matrix/fracture interface, the matrix flux contribution to fracture flow may be assumed proportional to either the pressure difference between matrix and fracture or to the averaged pressure gradient throughout the matrix block. The former assumption, introduced in fractured reservoir description by Barenblatt and Zheltov and Barenblatt et al. and employed by Warren and Root, has an advantage of simplifying the mathematical analysis of the flow problem and a disadvantage of not correctly representing either the mechanism of pressure readjustment between matrix and fracture by time-variant crossflow pressure readjustment between matrix and fracture by time-variant crossflow or the formation pressure response during the transitional time. According to this assumption, the matrix flux is independent of spatial position, which can be true only when pressure is linearly distributed in space-i.e., at a state of pressure equilibrium or at a pseudosteady-state time. This assumption, therefore, is often referred to as a "pseudosteady-state" or "lumped-parameter" flux assumption. It neglects the matrix storage capacitance by allowing an instantaneous pressure drop throughout the matrix as soon as fracture depletion occurs. The pressure response of a medium subject to this assumption has a characteristic S-shape transitional curve with an inflection point. The curve connects the initial pressure segment (the early-time fracture response) to the final pressure segment, representative of the late-time pseudosteady-state flow of an equivalent uniform medium that has fracture permeability and composite (the sum of fracture and matrix) storage. By contrast, the averaged gradient assumption on matrix-to-fracture crossflow, while somewhat complicating a mathematical analysis of the problem, has an advantage of more correctly describing the pressure problem, has an advantage of more correctly describing the pressure equilibration process that occurs during the transitional period. Matrix fluxes arising from fluid expansion forces are subject to Darcy flow and, thus, to diffusivity-type flow constraints. SPEJ p. 769

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