... relationships between fracture system geometry and underlying geologic mechanisms. The model employs Poisson plane and line processes as well as random spatial rotation and translation to represent fracture orientations, intensity, and relations to major geologic structures. The model is implemented...

... of a foundation rock block. Fig. 1 Explanation of nomenclature used. Fig. 2 Schematic description of the problem. is defined by nodes and faces in a 3-D orthogonal coordinate system. Each face of a volume element is a quadrilateral bounded by four nodes, and lies in one plane. Thus, a general representation...

... hydraulic fracturing Daneshy fluid pressure Reservoir Characterization pressure data pressure drop reservoir geomechanics Upstream Oil & Gas variation plane stress measurement principal stress Magnitude determination fracture perpendicular fracture length fracture plane...

... wellbore integrity Reservoir Characterization strength acoustic measurement Upstream Oil & Gas diameter small shale sample mechanical data empirical correlation mud weight window diffusion constant anisotropy shale plane sequence interaction Wellbore Design input parameter...

... Modeling & Simulation displacement wellbore orientation reservoir geomechanics strength Upstream Oil & Gas prediction Reservoir Characterization orientation Pariseau orthotropic elastic symmetry bedding heterogeneity plane symmetry evaluation anisotropy wellbore in-situ...

... Reservoir Characterization criterion failure mode plane structural geology artificial interstratified rock strength parameter discontinuity strength failure criterion Upstream Oil & Gas interstratified rock mass interstratified rock kaolinite orientation specimen model...

... and other forces, roof and wall wedges may fail either by falling, sliding or rotating out of their sockets. The factors that control wedge stability include geometry (the size, shape and spatial location of a wedge), the strength characteristics of the discontinuity planes that create the wedge...

... tech- niques that are used to that effect. During the excavation of some tunnels in Austria, it has been noticed that the displacement vector ori- entation in a vertical plane along the tunnel axis (settlement and longitudinal displacement compo- nent of the crown) could be a good indicator of changes...

... of inception of the DSSD. The characteristics of the various deposits indicate short-term episodes of deformation alternated by dormant stages. Deformations occurred along subvertical slip planes with relative uplift of the valley-side blocks, accompanied by toppling with fissure opening and slope steepening...

... of a true triaxial homogeneous state of compressive stresses (s 1 > s 2 > s 3 ). The samples were loaded in such a way that the maximum principal stress (s 1 ) was oriented at angle ß=90° to the foliation planes (which is the direction of the highest compressive strength), or at angle ß=30...

... geomechanics Upstream Oil & Gas confinement compression test Wellbore Design Simulation plane shear strength granite interaction fracture tessellation compression friction angle crack growth discrete rock crack growth axial splitting dilatancy Pacific Rocks 2000, Girard, Liebman, Breeds...

... ABSTRACT ABSTRACT Cracks develop in brittle materials under compressive load as a result of growth of microcracks causing irreversible damage and produce acoustic emission (AE). At high applied load, this damage causes strain localization leading to the ultimate fracture plane. Laboratory...

... heterogeneity dip angle geomechanical property University scale effect plane schistose rock tensile strength variation central cordillera schistosity anisotropy marble body colombian ande Abejorral Marble Body Pacific Rocks 2000, Girad, Liebman, Breeds & Doe (eds)O 2000 Balkema, Rotterdam, ISBN...

... a rift plane in the larger grain size specimens, while a vertical crack was induced normal to a rift plane in the smaller grain size specimen. We also found that the numbers of located AE sources increased with increasing grain size. In addition, magnitudes of breakdown pressure decreased with increasing...

... complex reservoir key-block tunnel stability analysis proceedings face 1 hydraulic fracturing unconditionally stable fracture pattern plane Upstream Oil & Gas assumption stability analysis direction cosine shear force normal force safety intersection realistic fracture...

... of the orientation of a plane in the rock mass. For example, an isoplethogram could be used to display the variation of normal stress on a plane that is rotated through the rock mass or to display the volume of rock that might become unstable due to an excavation plane that is rotated through the rock mass. Before...

... Characterization Upstream Oil & Gas riss shear direction reservoir geomechanics strength shear behavior natural language angularity friction rock joint morphology asperity Artificial Intelligence normal stress joint wall surface coefficient plane shear displacement dilatancy contact area...

... Downhole imaging techniques reveal that numerous discontinuities intersect a wellbore (Zemanek et al 1970, Shanks et al 1976, Suau and Gardner 1980, Paillet 1981, Heliot et al 1989, Plumb and Luthi 1989). Most of them are natural discontinuities such as fractures, faults, or bedding planes which have been...

... of the discs. The effect of rock anisotropy on tensile strength was determined by testing several discs with planes of anisotropy inclined at different angles to the loading direction. Tests were also carried out on initially cracked discs of one sandstone and one shale in order to determine the fracture...

... 1 INTRODUCTION ABSTRACT: We show that shear waves are especially sensitive to crack formation when the wave particle motion is perpendicular to the fracture plane, because these shear waves couple into interface waves that propagate along a fracture. Long before catastrophic failure, when...