The permeability of a rock is the measure of how effectively a fluid will flow through the rock. The permeability is related to the porosity and the shape, distribution and connectedness of the pores. That permeability may differ for different fluids / fluid phases – Relative Permeability (ie: the permeability of that rock to a […]
All solids can be categorized as either ductile or brittle, as associated to the material’s plastic deformation when it undergoes loading. Ductility is the ability of the solid material to deform plastically under loading while Brittleness is when the material has the tendency to not deform plastically under tensile loading, but instead to fracture / […]
There are four types of stresses that can act on rocks Confining stress – weight of all the rocks above Compression – forces that act towards each other make up compressional stress… such as at convergent / collisional boundaries of tectonic plates (Juan de Fuca Plate moving under North America, Indian Plate and Eurasian Plate […]
Pore pressure is the pressure of fluid in the pore space of rock, and when it exceeds the hydrostatic pressure, an overpressure situation occurs. Pore pressure definition and different pore pressure regimes (Normal, under and over pressure) Pore pressure in the sediments can be over pressure, under pressure or normally pressured. Normal pore pressure scenario […]
For a planar, clean (no infilling) fracture, the cohesion is zero and the shear strength is defined solely by the friction angle. The friction angle of the rock material is related to the size and shape of the grains exposed on the fracture surface. Thus, a fine-grained rock and rock with a high mica content […]
The unconfined compressive strength (UCS) of sedimentary rocks is a key parameter needed to address a range of geomechanical problems ranging from limiting wellbore instabilities during drilling, to assessing sanding potential and quantitatively constraining stress magnitudes using observations of wellbore failure. Various applications can be used for the development of rock strength profiles along the […]
In-situ stresses: Overburden and Minimum/Maximum Horizontal Stresses. Underground rocks and sediments are subjected stresses, the principal ones being: Vertical stress Minimum horizontal stress Maximum horizontal stress It is critical to identify the magnitude and direction of the horizontal stresses to understand stresses that are subjected to an element of rock in the formation. This information […]
Tensile strength is a measurement of the force required to pull something such as rope, wire, or a structural beam to the point where it breaks. The tensile strength of a material is the maximum amount of tensile stress that it can take before failure, for example breaking.
Shear Modulus is the ratio of Shear Stress to Shear Strain.
Geomechanics is the study of soil and rock structure and stability.
