.... The increase of crack density and porosity with temperature was found to be the main causes of degradation of physical properties. A generalized relationship between physical and mechanical properties and thermal induced damage was defined and proposed for a broad suite of marble rocks. The proposed...

... Upstream Oil & Gas shear wave response Reservoir Characterization crack density damani microseismic event polarization wave travel time shear velocity shear wave travel time secondary fracture main fracture transducer shear wave velocity fracture propagation propagation fracture...

... were interpreted by manual grain tracing and image processing to obtain digital phase and crack maps. Digitization of the sandstone microstructure in this way yields data on grain mineralogy, shape, (contact) size and orientation, as well as on coordination number and crack density and orientation. We...

... should be included in the simulations for their stability assessments. complex reservoir Engineering hydraulic fracturing element method crack density fracture strength microcrack fracture network Upstream Oil & Gas strength heterogeneity hydraulically crack tip spatial mesh...

... strain and l was the lateral strain. The strain caused by crack opening was ( )lelacevVlc 2 (2.2) Where: ac was the axial strain caused by cracks ev was the total elastic volumetric strain le was the lateral elastic strain. The crack density in different stress phase could be expressed...

... been conducted to investigate the compressional wave velocity and crack density after the thermal loading. Coconino sandstone has been used to investigate the change of rock properties after the thermal loading. 50.8 × 25.4 mm, 50.8 × 25.4 mm and 50.8×50.8 mm (diameter × thickness) samples are used...

... and andesite. It was shown that the crack growth behaviors in granite were anisotropic. When the crack propagates parallel to the plane in which the crack density of the pre-existing cracks was the highest, the crack velocity was the highest under the same water vapor pressure. Hence, it can be concluded...

.... These changes can be explained by the fact that deformation of cracks induced by UCT increases space to contain more water. Results of permeability tests for the deformed specimens are applicable to low permeable and impermeable class. Relationship of crack length and difference of crack density...

... strength grain marble wave speed measurement Reservoir Characterization microcrack crack length prediction peak strength Upstream Oil & Gas crack density reservoir geomechanics wing crack grain size initial crack density specimen fine grain marble marble crack growth...

... of the microscope, cracks of the four types were counted separately and their angles of inclination to the direction of ó were measured. In order to understand the variation of crack density with the distance from the main fracture, microcrack counting was also performed in three consecutive fields of view which...

... that propagated from right to left. Propagation slowed as fault tip approached steel endplug (left edge). Fault initiated at 25 ø to C l but rotated as it approached endplug. Crack densities in Table 1 were determined for regions A (10 mm)and B(2 mm from fault). Bottom: Line drawing of fault tip region. Insert...

..., is the ratio of the number of active cracks per unit volume to the total number of pos- sible cracks per unit volume. In the damage model, this is inter- preted as the current crack density divided by the maximum possible crack density of 9/16 (this maximum was derived by Budiansky and O'Connell, 1976): 16 C d...

... or 3. From the crack maps it is apparent that this rock fails through the development of microcrack arrays, which propagate in shear mode, preferentially along the compromise grain boundaries formed by impingement of quartz cement overgrowths. Reservoir Characterization crack density...

... enhancement borehole Simulation mchugh computational model History hydraulic fracturing fracture pattern crack density crack length laboratory experiment keough fracture distribution experiment fracture Chapter 52 USE OF LABORATORY-DERIVED DATA TO PREDICT FRACTURE AND PERMEABILITY ENHANCEMENT...

... Oil & Gas variation experiment tensile stress fragmentation shale gas Fluid Dynamics final report laboratory pulse shape seaman complex reservoir calculation input stress pulse shape curran oil shale hydraulic fracturing crack density borehole Devonian shale loading shockey...

... coefficient. (b Variation o/quality/actors with hydrostatic pressure. both the open and sliding crack density (Eq. 3) and the particle velocity Ou and (2) the density ofcracks sliding during an unloading cycle 3t' and loading are equal, then it becomes an easy matter to show that the wave equation becomes [4...