Flow-deformation response of dual-porosity media

Elsworth, D.; Bai, Mingxing

doi:10.1016/0148-9062(92)90790-7

Cited by 33 publications

(39 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to Elsworth and Bai [1992], the undrained response of a dual-porosity medium to stress loading is broken down into three stages: an initial stage when instantaneous pressuresppo andp•o are generated in the pores and fractures, respectively; a period during which these pressures dissipate by local fluid exchange between matrix and fractures at a rate determined by F in (22) Effective porosities and elastic moduli measured on four samples of unfractured core (36 mm diameter) taken from the borehole are summarized in Table 1. Porosities were obtained using the immersion method, and elastic constants were determined from standard uniaxial compression tests.…”

Section: Undrained Responsementioning

confidence: 99%

“…This relationship and the coupled continuity equations for fluid and solid flux in a deformable fractured medium are used to derive relationships for the undrained pore and fracture pressure responses to changes in confining stress. Two limiting cases are considered [Elsworth and Bai, 1992]: the initial, instantaneous pressure response in the pore space and fractures, and the later stage of pressure equilibrium between the two phases. Barometric pressure variations are related to changes in aquifer pressures, which, in turn, are related to water level fluctuations in wells, leading to expressions for the static-confined barometric efficiency of a dual-porosity medium in the two cases considered.…”

mentioning

confidence: 99%

See 1 more Smart Citation

A dual‐porosity model for water level response to atmospheric loading in wells tapping fractured rock aquifers

Desbarats¹,

Boyle²,

Stapinsky³

et al. 1999

Water Resources Research

View full text Add to dashboard Cite

Abstract. A fractured rock aquifer may be viewed as a permeable fracture network embedded within a less permeable porous matrix. This permeability contrast gives rise to distinct pressure fields in the pore space and fractures, and therefore to a response to atmospheric loading different from that of nonfractured porous media. Assuming that fracture sizes and orientations are uncorrelated and sufficiently random to ensure homogeneous and isotropic elastic behavior of the rock mass at the continuum scale, an effective stress model proposed by Tuncay and Corapcioglu [1995] is used to develop a linear elastic stress-strain relationship for dual-porosity media. Elastic constants of the fractured rock mass, required by the model, are estimated using theoretical relations derived by Budiansky and O'Connell [1976]. The stress-strain relationship and the coupled continuity equations for flow in deformable fractured media are combined to derive expressions for the undraiged, static-confined barometric efficiency of a dual-porosity medium. Two limiting cases are considered: the initial, instantaneous pressure response in the pore space and fractures due to a change of confining stress, and the later stage of pressure equilibrium between the two phases. The dual-porosity response model developed here may be used to characterize hydraulic properties in fractured aquifers, including low-porosity and low-permeability media. The model is evaluated on water level hydrograph data from a borehole tapping fractured volcanic rocks. Water level and barometric data are supplemented by independent measurements of matrix porosities, fracture spacing, and rock elastic properties, allowing an assessment of total porosity and specific storage at the site. For the observed static-confined barometric efficiency of 0.78 the instantaneous pressure response model yields plausible values for both parameters.

show abstract

Section: Undrained Responsementioning

confidence: 99%

mentioning

confidence: 99%

A dual‐porosity model for water level response to atmospheric loading in wells tapping fractured rock aquifers

Desbarats¹,

Boyle²,

Stapinsky³

et al. 1999

Water Resources Research

View full text Add to dashboard Cite

show abstract

“…The equivalent continuum can consider both the fracture and the matrix phases as separate and overlapping media, each one having a distinct flow regime and a separate fluid continuity equation [4]; if the model includes the HM coupling, the total strain results from the sum of the contributions of each phase (dual porosity/dual permeability model [5][6][7]). …”

Section: Introductionmentioning

confidence: 99%

The 2D hydro‐mechanically coupled response of a rock mass with fractures via a mixed BEM–FEM technique

Fidelibus

2007

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

SUMMARYThis paper describes the essential features of a numerical technique for the simulation of the coupled fluid flow and deformation in a 2D assembly of poroelastic blocks and transmissive fractures. The boundary element method (BEM) is applied to each block to reduce Navier and diffusion equations to a set of integral equations involving block boundary terms, whereas a Galerkin weighted-residuals finite element method (FEM) is applied to the fracture diffusion equations. In addition, fracture local equilibrium is rendered through spring-like equations relating the stresses to the relative displacements of the fracture walls. A time-marching process is implemented leading to an algebraic system where the right-hand side vector is built based on the collected solutions of the previous time steps. The technique requires the meshing of the fracture network only. The accuracy of the results is adequate even with relatively coarse meshes without the resort to small time steps at the beginning of the simulation. It furnishes outputs that focus only on the salient features of the response. The efficiency of the technique is demonstrated through the illustration of the results of three examples.

show abstract

“…Stress-Dependent Porosity and Permeability. The effective pressure of triple-continuum formation can be presented as [23] …”

Section: Constitutive Equationmentioning

confidence: 99%

Well Performance Simulation and Parametric Study for Different Refracturing Scenarios in Shale Reservoir

et al. 2018

View full text Add to dashboard Cite

Refracturing is an encouraging way to uplift gas flow rate and ultimate gas recovery from shale gas wells. A numerical model, considering the stimulated reservoir volume and multiscale gas transport, is applied to simulate the gas production from a refractured shale gas well. The model is verified against field data from a shale gas reservoir in Sichuan Basin. Two refracturing scenarios: refracturing through existing perforation clusters and refracturing through new perforation zones, are included in the simulation work. Three years after production is determined to be the optimum time for refracturing based on the evolution analysis of reservoir pressure, effective stress, fracture permeability, and gas recovery. The role that the hydraulic fracture conductivity and hydraulic fracture half-length play in gas production for different refracturing cases is explored. Pumping parameters of the refracturing job in Sichuan Basin are discussed combining with sensitivity analysis, and suggestions for pumping parameters optimization are proposed.

show abstract

Flow-deformation response of dual-porosity media

Cited by 33 publications

References 0 publications

A dual‐porosity model for water level response to atmospheric loading in wells tapping fractured rock aquifers

A dual‐porosity model for water level response to atmospheric loading in wells tapping fractured rock aquifers

The 2D hydro‐mechanically coupled response of a rock mass with fractures via a mixed BEM–FEM technique

Well Performance Simulation and Parametric Study for Different Refracturing Scenarios in Shale Reservoir

Contact Info

Product

Resources

About