... markedly from the short-term behaviour as defined by laboratory measurements on cores. The large scale stress field is found to depend mostly on the softer material that fills up the faults and hence results from the shear stress relaxation over a large number of pre-existing fractures and faults...

... suggest a presently active source of stress in this sedimentary system We propose that this stress is not related to tectonics but to pressure solution effects activated by pore pressure transients. These transients develop in the natural fracture system that affects limestone formations and are linked...

... de strasbourg France ABSTRACT Because hydraulic fracturies (HF) are always normal to the least m1mmum principal stress, mapping the geometry of hydraulic fractures helps map the trajectory of the minimum principal stress direction. In addition, measuring the pressure for which both faces...

... above lively city centre and fractured rock the project included an in-situ stress measurement campaign and rock mechanics stability studies, e.g. 2D and 3D numerical analyses and rock monitoring during construction. Rock stresses play often an important role in the rock engineering projects in Finland...

...7th International Symposium on ln-51tu Rock stress May 10-12,2016, Tampera, Finland Johansson & Raasakka (ads) ISBN 978-951-758-806-1 ISSN 0356-9403 ESTIMATION OF ROCK MASS DEFORMATION MODULUS USING THE FRACTURING INTERVAL LOADING Andrey Patulin (andrey.patutin@gmail.com) Institute of Mining SB RAS...

...711llntemational Symposium on ln-5ilu Rock Slress May 1D-12, 2016, Tampere, Finland Johansson & Raasakka (ads) ISBN 976-951-758-606-1 ISSN 0356-9403 HYDRAULIC FRACTURING STRESS MEASUREMENTS IN FRACTURED ROCK MASS AT A HYDROELECTRIC PROJECT *DS Subrahmanyam, **G Shyam, **K Vamshidhar, **Vikram...

... Abstract This study concerns dynamic simulations of earthquakes and the seismicity associated with induced slip of preexisting fractures in the rock mass for a repository for spent nuclear fuel planned to be constructed at Forsmark, Sweden. We use Particle Flow Code 2D (PFC 2D ) to model...

... Abstract Hydraulic fracturing technique is a measurement method of in-situ rock stress. This technique has the highest track record for techniques used in sub 1000 mater. This technique is comparatively simple and easy for in-situ stress measurement, because a pre-existing drilled borehole...

... that used various geophysical methods and hydraulic conductivity testing, a horizontal fracture without the characteristics of natural fracture was observed. In ground penetrating radar investigations fairly large reflectors occurred at the depth around 50 – 70 em and Mise-a-Ia-Masse surveys gave...

...7th International Symposium on ln-51tu Rock stress May 10-12,2016, Tampera, Finland Johansson & Raasakka (ads) ISBN 978-951-758-806-1 ISSN 0356-9403 INTEGRATED IN-SITU STRESS ESTIMATION BY HYDRAULIC FRACTURING AND BOREHOLE OBSERVATION AT EXP-1 HOLE IN POHANG OF KOREA Hanna Kim and Ki-Bok Min (kbmin...

... Geoscience Inc. Japan ABSTRACT We have proposed a new concept in which the in-situ stress state is determined by integrating the hydraulic fracturing data and the deformation of core samples. The integration leads to improve practicality and compensate disadvantages compared with the case using each data...

... ABSTRACT: The CSIRO overcoring stress relief and hydraulic fracturing methods are the most popular methods used for the measurement of in-situ stress at depth. One major advantage of the CSIRO overcoring stress relief method is that the three dimensional state of stress can be obtained...

... ABSTRACT: Hydraulic fracturing had been a widely applied method of measuring stresses in a drilled borehole. During the test procedure, induced forces due to the interaction between fluid flow and rock blocks deformation overcome the in-situ least stress. Thus the coupled hydromechanical...

... measurement geostress rock mass tectonic stress deformation soft rock Deformation Characteristic mining area Upstream Oil & Gas deep-buried tunnel high stress Crown fracture tunnel Rock Stress and Earthquakes Xie (ed.) © 2010 Taylor & Francis Group, London, ISBN 978-0-415-60165-8 Study...

..., that the tested rock masses of massive crystalline rocks behave similarly. Analysis of statistical data of minimum stress from shut-in curves and P-Q graphs are presented and compared with the leakage of a pressure tunnel in operation. It is also proposed that the ratio of initial fracture resistance to breaking...

... ABSTRACT: This paper introduces one method to detect the fractures induced during the hydraulic fracturing in-situ stress measurement process. This method can detect the hydraulic fracture fairly well, and can define the strike of induced fractures exactly so as to determine the orientation...

... ABSTRACT: During the large-scale hydraulic fracturing of thin interbedded sandstone reservoir (short for TISR), the fracture is propagated greatly along the fracture height direction, leading the length/height ratio of fracture usually smaller than 4. Because the interlayer is thin and weak...

... ABSTRACT: Hydraulic Fracturing, Hydraulic Tests on Pre-existing Fractures, sleeve reopening tests and the analysis of en echelon fractures developed in wells inclined to the principal stress directions, have helped determine the vertical profile of the complete stress tensor in a sedimentary...

... of preexisting fracture (HTPF) has similarity with hydrofracturing test but they are different. The hydrofracturing test (HF) is done in rock mass without discontinuity but HTPF is done in more discontinuity rock mass. In HF test direction of minimum stress can be measured by impression packer. HTPF and HFwere...

... 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...