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Application of high frequency seismic monitoring methods for the mapping of grout injections
89A
902194 Use of geophysical logs to estimate water quality of basal Pennsylvanian sandstones, southwestern Illinois Poole, V L; Cartwright, K; Leap, D Ground Water V27, NS, Sept, Oct 1989, P682-688 Fresh water found to depths of 300m in the basal Pennsylvanian sandstone aquifers of the Illinois basin offers a useful source of groundwater in an area of limited supply. Over 1000 drillers logs of water wells and 261 electrical logs of oil and gas wells and coal test borings were analysed to determine aquifer and groundwater characteristics, the extent of good quality water, and to determine the principal characteristics of the groundwater system.
902195 Application of the cross-spectral moving-window technique (CSMWT) to the seismic monitoring of forced fluid migration in a rock mass Frechet, J; Martel, L; Nikolla, L; Poupinet, G Int d Rock Mech Min Sci V26, N3/4, July 1989, P221-233 Adjacent seismic events or repeated artificial shots may exhibit similar waveforms. The differential characteristics of the waveforms may be accurately measured using the CSMWT. It is applied to study fluid migration in a hot dry rock geothermal reservoir. Two seismic doublets induced by fluid injection and five explosions were monitored. Detailed mapping of fracturation caused by injection was possible. Seismic velocity changes as low as 0.01% can be detected. The CSMWT is applicable at the 10-1000m scale.
902196 Application of high frequency seismic monitoring methods for the mapping of grout injections Majer, E L lnt J Rock Mech Min Sci V26. N3/4, July 19891 P249-256 Experiments were carried out at two sites in crystalline rock to develop methods of real-time grout injection mapping. Injection rates of 1-2001/min and pressures from 0.1-2MPa over hydrostatic were used with grouts of varying viscosity. Deviatoric stresses varied from zero at the surface to 15MPa at depth. Usable seismic energy between 1000-10,000Hz was indicated. Discrete seismic events (acoustic emission) and, in some cases, continuous seismic energy associated with sheets of very viscous grout were observed. A field monitoring system has been developed.
902197 VSP and cross-hole seismic surveys used to determine reservoir characteristics of a hot dry rock geothermal system Green, A S P; Baria, R; Jones, R Int J Rock Mech Min Sci V26, N3/4, July 1989, P271-280 Seismic emission has been monitored over 5 years during fracturing and circulation at the Camborne School of Mines geothermal project. The microseismic locations provide the only information about the position of the stimulated zone within the rock mass, hut evidence relating microseismicity to permeability is confusing. VSP and crosshole seismics have been used to help understand the relation between microseismic and hydraulic reservoirs. Signal attenuation and velocity across the reservoir have been mapped. Changes indicate that regions of microseismicity represent permanent increases in crack frequency and/or aperture.
902198 Geophysical exploration in the British coalfields Jackson, P J; Fairburn, C M; Whitworth, K R Miner Resour Engng 112, N2, April-June 1989, P123-149 Geological information concerning faults and other disturbances which can affect viability of an individual area of coal is essential to mine planning. Investigation techniques originally developed in the petroleum industry are now widely used in the UK coal industry. In-seam seismics to detect faults within a few hundred metres of a mine roadway, surface seismic techniques in coal exploration, and borehole geophysics in deep coal exploration are described and cases of their application presented. Potential future uses of radar and RIM (Radio Imaging Method) are briefly considered.
902199 Directional acoustic surveying instrument Treherne, D M; Harper, P G; Su, D SPE Drilling Engng V4, N2, June 1989, P104-I08 A single noise tool to determine the direction of a noise source, which operates in a surveyed borehole, has been developed. Directional accuracy of I-2 dog has been achieved in granite to depths of 600m. It can detect quasi-continuous (drilling) and pulse (explosion, sparker tool) sources. The vibrational response theory, design and construction of the instrument, and analysis of data to determine directionality are illustrated.
902200 Crosshole seismics: applications in mining Thill, R E; Jessop, J A; Friedel, M J Rock Mechanics as a Guide for E,Oicient Utilization of Natural Resources: Proc 30th U.S. Symposium, Morgantown, 19-22 June 1989 P335-342. Publ Rotterdam." A A Balkema, 1989 Two crosshole seismic systems developed by the USBM are presented. One operates at a central frequency of 20kHz for use in boreholes spaced 2-20m, the other at 1-2kHz for more distant spacings (40-300+m). Their applications in mining to investigate elastic and deformation properties, anisotropy, porosity, rock quality, geologic anomalies, water content, and stress state in the rock mass are described.
902201 Experimental study of line electrode method to detect underground cavities Ziaie, F; Peng, S S; Hsiung, S M Rock Mechanics as a Guide for E~cient Utilization of Natural Resources: Proc 30th U.S. Symposium, Morgantown, 19-22 June 1989 P369-376. Publ Rotterdam: A A Balkema, 1989 The line electrical method using at least three electrodes is proposed for location of subsurface cavities. One electrode is used as a sinkhole electrode, the others for different activations of line electrodes when the survey area is between one of the line electrodes and outside the other one. The theoretical model of the resistivity response to cavities is presented. Physical simulation in a tank model gives results consistent with theory, and suggests the method may be used to evaluate size and depth of cavities.
© 1990 Pergamon Press plc. Reproduction not permitted
902194 Use of geophysical logs to estimate water quality of basal Pennsylvanian sandstones, southwestern Illinois Poole, V L; Cartwright, K; Leap, D Ground Water V27, NS, Sept, Oct 1989, P682-688 Fresh water found to depths of 300m in the basal Pennsylvanian sandstone aquifers of the Illinois basin offers a useful source of groundwater in an area of limited supply. Over 1000 drillers logs of water wells and 261 electrical logs of oil and gas wells and coal test borings were analysed to determine aquifer and groundwater characteristics, the extent of good quality water, and to determine the principal characteristics of the groundwater system.
902195 Application of the cross-spectral moving-window technique (CSMWT) to the seismic monitoring of forced fluid migration in a rock mass Frechet, J; Martel, L; Nikolla, L; Poupinet, G Int d Rock Mech Min Sci V26, N3/4, July 1989, P221-233 Adjacent seismic events or repeated artificial shots may exhibit similar waveforms. The differential characteristics of the waveforms may be accurately measured using the CSMWT. It is applied to study fluid migration in a hot dry rock geothermal reservoir. Two seismic doublets induced by fluid injection and five explosions were monitored. Detailed mapping of fracturation caused by injection was possible. Seismic velocity changes as low as 0.01% can be detected. The CSMWT is applicable at the 10-1000m scale.
902196 Application of high frequency seismic monitoring methods for the mapping of grout injections Majer, E L lnt J Rock Mech Min Sci V26. N3/4, July 19891 P249-256 Experiments were carried out at two sites in crystalline rock to develop methods of real-time grout injection mapping. Injection rates of 1-2001/min and pressures from 0.1-2MPa over hydrostatic were used with grouts of varying viscosity. Deviatoric stresses varied from zero at the surface to 15MPa at depth. Usable seismic energy between 1000-10,000Hz was indicated. Discrete seismic events (acoustic emission) and, in some cases, continuous seismic energy associated with sheets of very viscous grout were observed. A field monitoring system has been developed.
902197 VSP and cross-hole seismic surveys used to determine reservoir characteristics of a hot dry rock geothermal system Green, A S P; Baria, R; Jones, R Int J Rock Mech Min Sci V26, N3/4, July 1989, P271-280 Seismic emission has been monitored over 5 years during fracturing and circulation at the Camborne School of Mines geothermal project. The microseismic locations provide the only information about the position of the stimulated zone within the rock mass, hut evidence relating microseismicity to permeability is confusing. VSP and crosshole seismics have been used to help understand the relation between microseismic and hydraulic reservoirs. Signal attenuation and velocity across the reservoir have been mapped. Changes indicate that regions of microseismicity represent permanent increases in crack frequency and/or aperture.
902198 Geophysical exploration in the British coalfields Jackson, P J; Fairburn, C M; Whitworth, K R Miner Resour Engng 112, N2, April-June 1989, P123-149 Geological information concerning faults and other disturbances which can affect viability of an individual area of coal is essential to mine planning. Investigation techniques originally developed in the petroleum industry are now widely used in the UK coal industry. In-seam seismics to detect faults within a few hundred metres of a mine roadway, surface seismic techniques in coal exploration, and borehole geophysics in deep coal exploration are described and cases of their application presented. Potential future uses of radar and RIM (Radio Imaging Method) are briefly considered.
902199 Directional acoustic surveying instrument Treherne, D M; Harper, P G; Su, D SPE Drilling Engng V4, N2, June 1989, P104-I08 A single noise tool to determine the direction of a noise source, which operates in a surveyed borehole, has been developed. Directional accuracy of I-2 dog has been achieved in granite to depths of 600m. It can detect quasi-continuous (drilling) and pulse (explosion, sparker tool) sources. The vibrational response theory, design and construction of the instrument, and analysis of data to determine directionality are illustrated.
902200 Crosshole seismics: applications in mining Thill, R E; Jessop, J A; Friedel, M J Rock Mechanics as a Guide for E,Oicient Utilization of Natural Resources: Proc 30th U.S. Symposium, Morgantown, 19-22 June 1989 P335-342. Publ Rotterdam." A A Balkema, 1989 Two crosshole seismic systems developed by the USBM are presented. One operates at a central frequency of 20kHz for use in boreholes spaced 2-20m, the other at 1-2kHz for more distant spacings (40-300+m). Their applications in mining to investigate elastic and deformation properties, anisotropy, porosity, rock quality, geologic anomalies, water content, and stress state in the rock mass are described.
902201 Experimental study of line electrode method to detect underground cavities Ziaie, F; Peng, S S; Hsiung, S M Rock Mechanics as a Guide for E~cient Utilization of Natural Resources: Proc 30th U.S. Symposium, Morgantown, 19-22 June 1989 P369-376. Publ Rotterdam: A A Balkema, 1989 The line electrical method using at least three electrodes is proposed for location of subsurface cavities. One electrode is used as a sinkhole electrode, the others for different activations of line electrodes when the survey area is between one of the line electrodes and outside the other one. The theoretical model of the resistivity response to cavities is presented. Physical simulation in a tank model gives results consistent with theory, and suggests the method may be used to evaluate size and depth of cavities.
© 1990 Pergamon Press plc. Reproduction not permitted