- Email: [email protected]
Characterization jointed systems by azimuthal resistivity surveys
21A of modelled stress distributions are presented. The stress field is seen to be affected by the anisotropic character of the different rock units and by any vertical changes in deformability properties occurring throughout the stratified rock mass.
891164 Status of in situ stress determination methods Haimson, B C
Key Qnestions in Rock Mechanics: Proc 29tb US Symposium, Minneapolis, 13-15 June 1988 P75-84. Publ Rotterdam: A A Balkema, 1988 The history of hydrofracturing is outlined and current uncertainties considered. Improvements in hydrofracturing, the fracture pressurisation method and the poroclastic model, and innovative new methods using borehole breakouts, borehole slotting, radial side hole stress relief, and differential strain curve analysis and anelastic strain recovery of drill cores are presented. Finally, hybrid methods using combinations of the above techniques as depths increase and conditions become more hostile are discussed.
891165 Triaxial primary stress measurements in Vihanti mine, Finland Sarkka, P S; Wohnlich, M; Pelkonen, K O Proc CARE 88 (Conference on Applied Rock Engineering), Newcastle, 6-8 January 1988 P193-201. Publ London: IMM, 1988
Stresses in Precambrian schists and skarns at 750m depth were determined using results of 5 triaxial probes and laboratory determined Young's modulus and Poisson's ratio. The data were entered into the Fennoscandia Rock Stress Data Base.
Remote sensing and photographic techniques See also: 891028 891167 Remote sensing adds a new tool to an explorntionist's kit Taranik, D L
Engng Min J V189, N7, July 1988, P38-40 An overview of remote sensing in mineral exploration. Spectral reflection of rocks, vegetation analysis, lineament analysis and computer techniques are outlined. 891168 Spatial remote detection and mineral exploration from 1972 to 1987, from Landnt to Spot (In French) Scanvic, J Y
lndustrie Minernle V70, NI, Feb 1988, P17-21 Spatial remote detection for mineral exploration has been developed over the past 15 years. Three case studies are presented for Yemen, Zimbabwe and Guinea, using data from the Spot satellite. Exploration, prospecting and exploitation are considered. 891169 Methods for contextual classification of remotely sensed data Fatti, L P; Eiphinstone, C D; Lonergan, A T Proc APCOM 87, Johannesburg, 19-23 October 1987 V2, P13-29. Publ Johannesburg: SAIMM, 1987
Classification of a remotely sensed scene should take into account that data from neigbouring pixels are, in general, spatially dependent. Various approaches towards incorporating this correlation when classification is made on the basis of spectral reflectance data are examined.
Structural and geotechnical mapping 891166 Fault-plane analysis of microseismicity induced by fluid injections into granite Green, A S P; Baria, R; Madge, A; Jones, R
Proc 23rd Annual Conference of the Engineering Group of the Geological Society, Engineering Geology of Underground Movements, Nottingham, 13-17 Sept 1987 P497-509. Publ Nottingham: University of Nottingham, 1987 At the site of a hot dry rock geothermal energy project in Cornwall, UK, in situ stress has been measured by overcoring at the surface and hydraulic fracturing at depth 2kin. Jointing has been assessed by surface mapping and borehole cameras. The microseismic activity associated with the creation of the reservoir has been analysed by the fault plane method. Calculated stress and jointing data are consistent with other measurements. At economic depths for geothermal projects (6kin) the fault plane method may be the most appropriate tool for obtaining stress and jointing data.
891170 Characterizing jointed systems by azimuthal resistivity surveys Taylor, R W; Fleming, A H
Ground Water V26, N4, July-Aug 1988, P464-474 Bulk joint properties cannot be precisely determined from measurements on individual fractures at isolated outcrops. Azimuthal resistivity surveying is proposed as a method to characterise bulk in situ fracture geometry. The method uses conventional equipment and involves rotating a Wenner array about a fixed centre point and measuring apparent resistivity as a function of azimuth. Properties of the subsurface joint system are determined by analysis of the apparent resistivity ellipse generated. The theory of the technique is illustrated, and results of field measurements, which generate joint strikes and porosities of jointed bedrock in good agreement with other methods, are presented. 891171 Seismic hazard in the northern North Sea Bungum, H; Gudmestad, O T; Loken, T; Wood, R M; Nadim, F; Swearingen, P H; Woo, G
Norw Geotech lnst Publ NI70, 1988, 8P
Site Investigation and Field Observation See: 891068
The northern North Sea is a region of moderate seismicity, where earthquakes of magnitude Ms greater than 5.5 are rare. Because of commercial activity in the area, seismic hazard analysis has been undertaken. The basic approach, founded on the record of past earthquakes,is described. Regional and local geological analysis, to find potential active zones, and seismological analysis, involving data acquisition, source modelling,
© 1989 Pergamon Press pie. Reproduction not permitted
891164 Status of in situ stress determination methods Haimson, B C
Key Qnestions in Rock Mechanics: Proc 29tb US Symposium, Minneapolis, 13-15 June 1988 P75-84. Publ Rotterdam: A A Balkema, 1988 The history of hydrofracturing is outlined and current uncertainties considered. Improvements in hydrofracturing, the fracture pressurisation method and the poroclastic model, and innovative new methods using borehole breakouts, borehole slotting, radial side hole stress relief, and differential strain curve analysis and anelastic strain recovery of drill cores are presented. Finally, hybrid methods using combinations of the above techniques as depths increase and conditions become more hostile are discussed.
891165 Triaxial primary stress measurements in Vihanti mine, Finland Sarkka, P S; Wohnlich, M; Pelkonen, K O Proc CARE 88 (Conference on Applied Rock Engineering), Newcastle, 6-8 January 1988 P193-201. Publ London: IMM, 1988
Stresses in Precambrian schists and skarns at 750m depth were determined using results of 5 triaxial probes and laboratory determined Young's modulus and Poisson's ratio. The data were entered into the Fennoscandia Rock Stress Data Base.
Remote sensing and photographic techniques See also: 891028 891167 Remote sensing adds a new tool to an explorntionist's kit Taranik, D L
Engng Min J V189, N7, July 1988, P38-40 An overview of remote sensing in mineral exploration. Spectral reflection of rocks, vegetation analysis, lineament analysis and computer techniques are outlined. 891168 Spatial remote detection and mineral exploration from 1972 to 1987, from Landnt to Spot (In French) Scanvic, J Y
lndustrie Minernle V70, NI, Feb 1988, P17-21 Spatial remote detection for mineral exploration has been developed over the past 15 years. Three case studies are presented for Yemen, Zimbabwe and Guinea, using data from the Spot satellite. Exploration, prospecting and exploitation are considered. 891169 Methods for contextual classification of remotely sensed data Fatti, L P; Eiphinstone, C D; Lonergan, A T Proc APCOM 87, Johannesburg, 19-23 October 1987 V2, P13-29. Publ Johannesburg: SAIMM, 1987
Classification of a remotely sensed scene should take into account that data from neigbouring pixels are, in general, spatially dependent. Various approaches towards incorporating this correlation when classification is made on the basis of spectral reflectance data are examined.
Structural and geotechnical mapping 891166 Fault-plane analysis of microseismicity induced by fluid injections into granite Green, A S P; Baria, R; Madge, A; Jones, R
Proc 23rd Annual Conference of the Engineering Group of the Geological Society, Engineering Geology of Underground Movements, Nottingham, 13-17 Sept 1987 P497-509. Publ Nottingham: University of Nottingham, 1987 At the site of a hot dry rock geothermal energy project in Cornwall, UK, in situ stress has been measured by overcoring at the surface and hydraulic fracturing at depth 2kin. Jointing has been assessed by surface mapping and borehole cameras. The microseismic activity associated with the creation of the reservoir has been analysed by the fault plane method. Calculated stress and jointing data are consistent with other measurements. At economic depths for geothermal projects (6kin) the fault plane method may be the most appropriate tool for obtaining stress and jointing data.
891170 Characterizing jointed systems by azimuthal resistivity surveys Taylor, R W; Fleming, A H
Ground Water V26, N4, July-Aug 1988, P464-474 Bulk joint properties cannot be precisely determined from measurements on individual fractures at isolated outcrops. Azimuthal resistivity surveying is proposed as a method to characterise bulk in situ fracture geometry. The method uses conventional equipment and involves rotating a Wenner array about a fixed centre point and measuring apparent resistivity as a function of azimuth. Properties of the subsurface joint system are determined by analysis of the apparent resistivity ellipse generated. The theory of the technique is illustrated, and results of field measurements, which generate joint strikes and porosities of jointed bedrock in good agreement with other methods, are presented. 891171 Seismic hazard in the northern North Sea Bungum, H; Gudmestad, O T; Loken, T; Wood, R M; Nadim, F; Swearingen, P H; Woo, G
Norw Geotech lnst Publ NI70, 1988, 8P
Site Investigation and Field Observation See: 891068
The northern North Sea is a region of moderate seismicity, where earthquakes of magnitude Ms greater than 5.5 are rare. Because of commercial activity in the area, seismic hazard analysis has been undertaken. The basic approach, founded on the record of past earthquakes,is described. Regional and local geological analysis, to find potential active zones, and seismological analysis, involving data acquisition, source modelling,
© 1989 Pergamon Press pie. Reproduction not permitted