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Patterns to ores in layered rocks
Economic Geology, 1960Distribution patterns of syngenetic ore bodies in layered rocks correspond in area, symmetry, and metal variation with the rock facies structures. Distribution patterns of epigenetic ore bodies either correspond to antecedent and contemporary tectonic structures or deviate systematically under their influence.
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Differentiated layering in metamorphic rocks
Earth-Science Reviews, 1990Abstract Metamorphic or differentiated layering is best developed in low prograde metamorphic rocks such as slates and metaturbidites and is most easily recognised where it cuts a demonstrably earlier layering such as bedding. It commonly occurs as an axial plane foliation and typically comprises layers rich in phyllosilicates and opaque minerals ...
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Airflow through crushed-rock layers
2011 Second International Conference on Mechanic Automation and Control Engineering, 2011Pressure drops through packed concrete spheres and crushed rocks were investigated by wind tunnel experiments. The diameters of concrete spheres were 0.041 m and 0.052 m, respectively. The mean particle size of the crushed rocks was 0.096 m. The experimental results show that the Ergun equation with revised coefficient values can be used to predict ...
null Yuanming Lai +2 more
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Statistics of joint spacing in rock layers
Geological Magazine, 2012AbstractWe show that spacing statistics can be obtained for all fracture densities by the same equation. Using the simple ‘shear lag’ theory, it is demonstrated that the results adequately fit experimental measurements. Theoretically, it is shown that two parameters are sufficient to characterize all spacing distributions.
AVINOAM RABINOVITCH +2 more
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Mechanisms of dike propagation in layered rocks and in massive, porous sedimentary rocks
Journal of Geophysical Research: Solid Earth, 1991The mechanisms of dike propagation are analyzed through detailed examination of small structures associated with the dike intrusion. Exposures in the Ramon area, Israel, offer an opportunity to evaluate theoretical models of tensile fracture propagation and to better understand the factors governing the dike geometry.
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Ambiguity of elasticity measurements in layered rocks
SEG Technical Program Expanded Abstracts 2007, 2007Different boundary conditions applied to finite-size, heterogeneous rocks result in different average or apparent elastic stiffnesses. In statics, the apparent stiffness tensors that correspond to the homogeneous stress and homogeneous strain boundary conditions provide the lower and upper bounds for the true or effective stiffness tensor.
Vladimir Grechka, Maria Alejandra Rojas
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Compositional convection and layering in a rock melt
Nature, 1987When a crystal grows (or dissolves) in a solution it becomes surrounded by a thin boundary zone of liquid that is relatively depleted (or enriched) in crystal components. The compositional difference and, hence, the horizontal density gradient that exist in this zone, may cause it to convect away from the crystal1. This process of natural convection is
C. H. Donaldson, D. L. Hamilton
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Permeability anisotropy of layering rock model
AIP Conference Proceedings, 2015Computer models of layering system were generated to analyze the effect of layering to the permeability anisotropy. Six layering models were created using non-spherical grain models. Each model consist of three layers with different thickness ratios. The permeability of the generated models were calculated using Lattice Boltzmann Method.
Zaroh Irayani +2 more
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Study of the formation of ice and rock filling with layer-by-layer freezing of rocks
Journal of Mining Science, 1998G. P. Neobutov +2 more
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Fracture Behaviour of Layered Rocks with Alternating Stiff and Soft Layers
2022Various subsurface engineering activities, including the stimulation of unconventional hydrocarbon reservoirs, the development of geothermal energy and the drilling and blasting operations, have been increasingly carried out in sedimentary rocks with layering structures.
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