... principal stress direction reservoir geomechanics stress component stress determination determination packer equation Upstream Oil & Gas borehole borehole wall hydraulic testing fracture 7th International Symposium on ln-8ilu Rock SU'ess May 1D-12, 2016, Tampers, Finland Johansson...

... hydraulic fracturing impression packer impression method principal stress Reservoir Characterization orientation borehole wall horizontal principal stress borehole wall image new method maximum horizontal principal stress Rock Stress and Earthquakes Xie (ed.) © 2010 Taylor & Francis Group...

... on the pressure distribution in the borehole wall is simulated. According to the mathematical model, the various parameters which effect the collapsed pressure for borehole stability are analyzed in detail, including non-uniform in-situ stress coefficient, hole size, permeability, pore pressure, internal friction...

... ABSTRACT: Stress measurements were undertaken in a significantly inclined borehole (denominated OL-KR40) at the Olkiluoto site, Finland, resulting in en echelon fracturing of the borehole wall. The failure to successfully stimulate pre-existing fractures using the HTPF-technique, which...

... a tensile circumferential stress around the borehole. When the tensile stress exceeds the strength of a rock and the stress concentration by the borehole, fracture initiation occurs on the borehole wall. Assuming a vertical borehole which is free from pre-existing/natural fractures, the vertical fractures...

... of hydraulic fracturing (Cai 2000). A section of a borehole is sealed off by use of two inflatable rubber packers sufficiently pressurized so that they adhere to the borehole wall. Water is pumped under constant flow rate into the section, gradually raising pressure on the borehole wall until fracture...

... and stress-state around the borehole. Specifically, when a borehole wall is loaded by a borehole-jack, a pair of new fractures will be induced oppositely in parallel to the borehole axis. After unloading, if the same place on the borehole wall is loaded again by a jack, the pair of fractures will be opened...

... breakout span as it varies with depth is obtained. Laboratory tests of core samples in a polyaxial cell render the true triaxial strength criterion of the rock. Using the condition of limit equilibrium between the local state of stress at the edges of breakout-borehole wall intersections and the strength...