The shearing of natural fractures is important in the permeability enhancement of shale gas reservoirs during hydraulic fracturing treatment. In this work, the shearing mechanisms of natural fractures are analyzed using a newly proposed numerical model based on the displacement discontinuities method. The fluid-rock coupling system of the model is carefully designed to calculate the shearing of...

In this paper we seek to relate the influence of the geometry and distribution of fracture aperture to the fluid flow properties of the fracture. Coupling fluid flow and transport experiments to high-resolution laser scanning confocal microscopy (LSCM) enables tracking of local fluid velocity and particle trajectories, and allows direct quantification of variations caused by surface roughness. ...

We argue that fracture surfaces may exhibit anomalous dynamic scaling properties akin to what occurs in some models of kinetic roughening. We determine the complete scaling behavior of the local fluctuations of a brittle fracture in a granite block from experimental data. We obtain a global roughness exponent x51.2 which differs from the local one, x loc50.79. Implications on fracture physics a...

based on volume-averaging concepts, liquid migration along subvertical fractures typically is predicted to be Field and laboratory tracer experiments were conducted to investisubject to strong matrix imbibition into the partially satugate the extent of tracer imbibition and penetration into unsaturated, fractured rock matrix at Yucca Mountain, Nevada. Field experiments rated rock (e.g., Wang an...

Transient heat andor fluid mass exchange between the permeable fracture system and the surrounding relatively impermeable country rock can be treated in geothermal reservoir simulators using the “MINC” technique. This approach typically requires about an order of magnitude more computer time than the analogous “porous medium” problem. Under practical conditions, the problem can often be lineari...

in this work, the mechanism for fracture of brittle substances such as rocks under a uniform normal tension is considered. the oriented straight micro-cracks are mostly created in all the polycrystalline materials resulting from the stress concentrations. the present work focuses on the interactions of the pre-existing micro-cracks, which can grow and propagate within a rock-like specimen. the ...

The purpose of this paper is to investigate the application of a combined finite-discrete element program, such as ELFEN, for the simulation and prediction of backfill stope failure risks due to blast loading effects in underground mines. A real size of a backfilled stope blasted in the nearby rock of the paste fill is modelled. The dynamic fracture propagation and fragmentation in rock and the...

When examining a rock mass, joint sets and their orientations can play a signiicant role with regard to how the rock mass will behave. To identify joint sets present in the rock mass, measurements of the orientation of individual fractures can be measured on exposed rock faces and the resulting data examined for heterogeneity. In this paper, the EM algorithm is utilized to t mixtures of Kent co...

Abstract. A numerical procedure for the evaluation of equivalent permeability tensor for fractured vuggy porous media is presented. At first we proposed a new conceptual model, i.e., discrete fracture-vug network model, to model the realistic fluid flow in fractured vuggy porous medium on fine scale. This new model consists of three systems: rock matrix system, fractures system, and vugs system...