... deformation modalities observed in several rock types affect release of helium. Axial compression tests with granite, rhyolite, tuff, dolostone, and sandstone - under vacuum conditions - were conducted to measure the transient release of helium from each sample during crushing. It was found that, when crushed...

... through porous rocks. Unclear also is the effect of temperature, pressure, and water saturation on the breakthrough times of the gaseous species. The objective of this work is to evaluate the breakthrough times of the gaseous species through tuff rocks by accounting for the porous rock matrix, fracture...

... fracturing explosion reservoir geomechanics cavity geological subdiscipline plate tectonics reservoir characterization vorobiev saturation national laboratory pressurized underground cavity fracture tuff underground explosion calculation implication cavity radius journal radial fracture...

... is to experimentally study two typical semi-circular bending methods for determining mode I fracture toughness of tuff. Particularly, the semi-circular bend (SCB) specimen and cracked chevron notched semi-circular bend (CCNSCB) specimen are used to determine mode I fracture toughness of fresh lapilli-ash tuff...

.... This paper discussed the factors affecting the loading rate dependence of rock strength, comparing the n values obtained in this study and in the authors' previous studies. reservoir geomechanics failure criterion loading rate dependence tuff stress-strain curve Fukui andesite test condition...

... Abstract: Creep/static fatigue experiments were conducted on samples of highly-welded, non-lithophysal Paintbrush Tuff. The tests were conducted at a confining pressure of 5.0 MPa, a pore water pressure of 4.5 MPa, and a temperature of 125°C. The specimens were rapidly loaded to a constant...

... Abstract: Triaxial test was carried out under confining pressure of 1-15 MPa at 22°C by using an ultra compact triaxial cell on Shikotsu welded tuff, Kimachi sandstone and Inada granite. The permeability was measured by using constant flow or transient pulse method. In case of tuff...

... ABSTRACT: This study discusses the stress-dependant brittle-to-ductile deformations observed in a tuff formation of the Newberry Volcano field in Oregon, USA, which is encountered in geothermal wells drilled to 3066 m (10,060 ft). Laboratory tests investigate the mechanical behavior...

... ABSTRACT: Twenty seven triaxial compression tests have been conducted on welded tuff at constant and controlled axial piston displacement rates. The piston displacement rates were then converted to axial stress rates according to a nearly linear load-displacement relation. Specimens were...

... in elsewhere[9] about ice lens segregation of welded tuff shown in the figure. Mineral composition of the welded tuff was about 15% of 0.2 to 2 mm plagioclase and 0.2 to 1 mm of quartz as phynocryst, and 85% of vitreous groundmass. The groundmass was determined as clinoptilolite and chlorite. This welded tuff...

... ABSTRACT: One hundred thirty eight Brazilian tests have been conducted to investigate the strain rate dependency of the tensile strength of the welded Topopah Spring tuff. The tests were carried out under varied loading conditions: with cardboard and without cardboard; different specimen...

... ABSTRACT: Fracture heterogeneities have been measured by air-permeability tests in five niches located in two welded tuff units at Yucca Mountain. Niches are room-size excavations along underground drifts. The air permeability along borehole intervals at each niche site exhibits strong local...

..., respectively. The relationships of the cast and cored specimens were compared with data from previous studies of tuff. The R2 of the tuff group is 0.82. The correlation coefficients of each grouping were tested against each other in a test for equality with a level of significance of 0.05. This statistical...

... power input Upstream Oil & Gas experiment Modeling & Simulation thermal hydraulic chemical experiment secondary mineralization column test 3 column test 1 watt saturation Column Test permeability Column Experiment Redistribution tuff mass flux Rock Mechanics in the National...

... ABSTRACT: Lateral and vertical variabilities in the bulk and mechanical properties of silicic volcanic tuff at the potential nuclear waste repository site in Yucca Mountain, NV have been evaluated. Laboratory measurements have been performed on tuff specimens recovered from boreholes located...

... performance of cement plugs under in-situ conditions (i.e. as affected by scale, and field installation and environment), and particularly about their long-term sealing effectiveness. The objectives of the research are to determine the hydraulic conductivities of the cement plug, host tuff...

... waste repository at Yucca Mountain, Nevada. This report addresses the effect of strain rate and heterogeneity on the strength and moduli of fully saturated tuff specimens from the potential repository horizon at Yucca Mountain. EXPERIMENTAL PROCEDURE A series of constant strain rate, uniaxial...

... ABSTRACT: The effects of loading frequency, strain amplitude, and saturation on elastic moduli and attenuation have been measured in samples of the Topopah Spring Member welded tuff. Four different laboratory techniques have been used to determine Young's modulus and extensional wave...

... subcritical crack growth borehole Kemeny damage model Yucca Mountain boundary condition emplacement tuff Scenario Rock Mechanics as a Multidisciplinary Science, Roegiers (ed.) ¸ 1991 Balkema, Rotterdam. ISBN906191 194X Time-dependent borehole stability under mechanical and thermal stresses...

... rate plug permeability cement borehole plug rock bridge sample plug permeability tuff Nuclear Regulatory Commission borehole plug Daemen normalized flow rate finite element analysis conductivity interface Rock Mechanics as a Multidtsctplinary Sctence, Roeg/ers (ed ) ¸ 1991 Balkema...