... Abstract Horizontal stress magnitudes are determined from dynamic elastic moduli, effective vertical stress and a wellbore stress model using nonlinear elasticity in rock formations with medium to high porosity (15 to 40%). Full-waveform borehole acoustic waves (flexural and Stoneley...

... production blast holes so as to find borehole stability problems. A total of 298 blast holes were filmed. There were eight types of stability problems identified in the blast holes. These are shear zone, loose rock, cave, crack, deformation, stone jammed, spalling and rock breakage. Among these problems...

... system in the deep borehole were carried out in Beishan, Gansu Province, NW China—the most potential site for China's geological repository for high level radioactive waste. In the granitic rock, fractures do often exist in form of a network. If water was injected into the packed-off interval, where...

... hole 4 delay time tensile stress wave blast-induced dynamic rock fracture metals & mining strength free surface compressive wave blasthole detonator position borehole explosive charge dynamic fracture rock fracture hydraulic fracturing dynamic rock fracture stress wave stress wave...

... control is recognized as directional hydraulic fracturing through creating directional fractures in roof to weaken its integrity. A comprehensive investigation into stress distribution around borehole and fracture propagation patterns was carried out in this paper through theoretical analysis, numerical...

... structure features, magnitudes and orientation of far-field stresses of planned project area shall be studied in detail. The hydrofracturing measurements has been done in five boreholes of about 140m deep; for the scattered measurement results, it is hard to find out the intrinsic relationships between...

... ABSTRACT A stress calculation method was proposed for the new stress measurement technique using the borehole slotter device. The 2D borehole slotter is an instrument which is used in HQ boreholes (96–104 mm diameter), and allows calculation of 2D stress tensor in a plane normal...

... Reservoir Characterization roof rock dominant frequency fracture foliation Upstream Oil & Gas borehole gneiss rockburst propagation microseismic monitoring fractured rock investigation rock fracture process frequency seismic investigation geophone seismic velocity mining...

... of displacement stress and load appeared. Following we will analysis these difference from two aspects. 4.1 Displacement analysis Displacement results come from sloping surface monitoring, multi-point extensometer and inclined borehole monitoring data. (1) Sloping surface displacement Nine points were specified...

.... The spent fuel from nuclear power plants will be reprocessed first, followed by vetrification and final disposal. A conceptual repository 3D configuration comprises a single vertical borehole in a continuous and homogeneous hard rock, containing a canister surrounded by an over-pack and a bentonite layer...

... borehole Fracture Zone dust collector tunnel auxiliary method support pattern stabilization ISRM-Sponsored International Symposium on Rock Mechanics: Rock Characterisation, Modelling and Engineering Design Methods 1 INTRODUCTION Mountain tunnels are linear structures constructed in inner ground...

... Reservoir Characterization Fluid Dynamics borehole investigation Upstream Oil & Gas hydraulic conductivity field investigation structural geology grouted rock mizunami underground research laboratory grout penetration inflow main shaft side rock mass penetration flow in porous...

... of the in situ state of stress, to be used as input to the numerical models of the underground structures. At the design stage, six STT (strain tensor tube) overcoring tests were carried out in 2 boreholes. A specific methodology was used for global analysis of the test results, in order to obtain the most...

... structural geology url area borehole investigation mudstone url project characteristic Upstream Oil & Gas investigation geomechanical model diatomaceous mudstone sedimentary soft rock rock mass Reservoir Characterization underground facility borehole mechanical property...

... in sedimentary and volcanic highly jointed rocks of Triasic and Jurasic ages. The length of the shaft is 450m and its diameter is 6m with 65 degree inclination relatively south-north trend. The results of geo-engineering surveys using boreholes and statistical joint-graphics of stereograms reveal at least two...

... Upstream Oil & Gas borehole reservoir geomechanics orientation Reservoir Characterization measurement campaign site investigation hydraulic fracturing stress magnitude Christiansson forsmark site Drilling investigation stress estimation fracture repository Sweden Magnitude...

... central borehole, and six more boreholes around the adjacent station shaft, the assumed mean rock cover of just 3 m above the 20 m deep cavern arch, proved locally to be more than 10 m in error, due to a buried ridge of rock running high above the cavern arch, with one fateful low point exactly where...

... are necessary, especially for deviated wells because of the complexity of stress state and the fracture geometry around an inclined borehole. Most numerical simulators do not consider hydro- mechanical interactions, but simulate geohydraulic or geomechanical processes. The FDM program FLAC3D is a specific three...

... acting against the walls of a borehole. Displacement of loading plates in PLT is measured by means of multi-point extensometers in the rock mass as shown in Fig. 2 and for the FDT by three LVDTs installed inside the probe. The interpretation of the measurements from such a test requires considerable care...

... geomechanics orientation borehole intermediate principal stress repository Magnitude ISRM-Sponsored International Symposium on Rock Mechanics: Rock Characterisation, Modelling and Engineering Design Methods 1 Comparison of the minimum horizontal stress from overcoring and hydraulic fracturing...