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Censoring and edge effects in areal and line transect sampling of rock joint traces
101A
Valmes of u.n:lralned modulus, drained modulus, umlralmed shear strength amd coefficient of consolidatiom are determined in a straightfc~ard test ~a~ecedure. The furdamental mature of the test as well as preliminary results suggest that e ~ valuable data may be obtained at relatively low cost. Auth.
Texture, structure, composition
and dmsity 82~o~8 C ~
AND EDGE EFFECTS IN AREAL AND LINE TRA~ SAMPLING OF ROCK JOINT TRACES i Laelett, G M J I ~ Ass Math Geol# VI~, N2, April 1962,
lm_2~-l~) Reviews techniques for correcting far bias when Inecm~xlete observations fo~nn part of a data set. The ~w~larities and differences between biases due t o @mmmcrlng and edge effects are emphasised, the lat%e~ Being of i ~ a n c e when the dlstributicm ~f ~oint traces is estimated from an expos~s~e. A mew technique for ar~lysing line transect data is presented, and a new analysis of Im~bl~hed ~ata on Joint trace l e r ~ s is given. Auth. 32 refs.
825019 SOME
EFFECTS OF COMPACTION AND GE~0GICAL TIME ON THE PORE PAR~,'E~S OF ARGILLACEOUS ROCKS Borst, R L Sedimentology, V29, N2, April 1982, P291-298
Graphical statistics have been applied to the pare-size distribution curves of argillaceous rocks to characterize the charges in pore parameters that result from compaction and geological time. The most striking characteristic of recently deposited sediment is the high variability in mean pore size and in the sorting and skewness of the pore system. The mean pore size of shales decreases with increasing compaction and approaches a limiting value of about 3.Snm at depth. Sediments buried to a depth of 500m or less exhibit a porosity range of 40-85 per cent: below 50Ore, porosity decreases linearly with burial depth. No correlation exists between the surface area of shale pore systems and depth of btmial, geological age, and the pore parameters mean pore size, sorting, and skewness.
825020
PLUMMRT BAI~NCE - A I~Y~ENTIAL TOOL FOR SUBSIEVE PARTICLE SIZE ANALYSIS. TECHNICAL NOTE NagaraJ, T S; Sivapullalah, P V Geotech Test J, V4, N1, March 1981 , PB6-40 An experimental investigation was carried out to compare the plummet balance method with two other methods of subsieve particle size ar~ysis, the pipette and the hydrometer methods, and to identify critical factors to be considered when using this method. The experiments were carried out on kaolinite and fire clay. Results i:~licate that for a plummet immersion of 20cm the particle size distribution wottld be similar to that obtained by the hydrometer and pipette methods.
Attempts to relate the closeness of packing of ions expressed as the cation packing index (k-value) to the physical ~roperties density amd seismic velocity. The study relates to the deteTruination of the mineralogy of the lithosphere from the earth's surface. 825022 RELATIONSHIPS BEI'w-EEN THE P~.'I'KOFHYSICALPROf."RTIES DENSITY, SEISMIC VELOCITY, HEAT GENERATION, AND MINERALOGICAL CONSTITUTION Rybach, L; Buntebarth, G Earth Planet Sci Lett, V57, N2, Feb 1982,
P367-376 Mineralogical constitution is represented by the cation fraction (k-value). The paper reports density, P wave velocity and heat generation measurements on i00 crystalline rocks (granophyres, granites, granodic~ites, tonelites, diorites, gabbros, amphibolites, hc~nblendites, pyroxenltes, ultrabasic rocks) and establishment of relationships by regression analysis.
Fracture processes 825023 ACOUSTIC EMISSION STUDY OF MICROFRACTURING DURING THE CYCLIC LOADING OF WESTERLY GRANITE Sondergeld, C H; Estey~ L H J Geophys Res, V86, N ~ , I0 April 1981, P2915-2924 A rectamgular prism of Westerly granite was defc~ned in a umiaxial cycling experiment. Acoustic emission activity was recorded usirg eight transducers in real time. Hypocenters of ll6 events were determir~d using a standard least squares approach. The cumulative distribution of hypocenters documents the strongly anisotroplc development of dilatancy in Westerly granite. Volumetric strain, differential stress, acoustic emission event rate 3 amd cumulative numbers were continuously measured during the experiment. The c~nulative number of events per cycle generally decreased with the number of cycles. The majority of events occurred upon loading. Those that occurred during unloading were few in n ~ e r and not as systematically related to stress.
82502~ STUDY
ON THE TIME-DEPENDENT MICROFRACTURING AND STRENGTH OF OSHIMA GRANITE Sano, O; T~rada, M; Ehara, S Tectonophysics, vS~, N2-4, 20 April 1982 , PB43-362
Unlaxial compression tests wh~re axial strain rate or dilatant volumetric strain rate was kept constant were carried out using a servo-controlled hydraulic testir~ machine. A theory based on the asst~nption of re-diatribution of ~re-existimg microcracks due tc subcritical crack growth was examined, amd theoretical results were found to agree well with experiment. The acoustic emissions were monitored as a measure of crack growth.
Strength characteristics 825021 DENSITY AND SEIS~-IC VELOCITY IN RELATION TO MI~OGICAL CONSTITUTION BASED ON AN IONIC MODEL FOR MIN~qALS Buntebarth, G Earth Planet Sci Lett, V57, N2, Feb 1982,
P358-366
It.M.M.S. 19/5--D
See also: 82504% 825209 825025 INCREMENTAL LOADING DEVICE FOR STRESS PATH AND STRENGTH TESTING OF SOILS NagaraJ~ T S; Murthy, M K; Sridharan, A
Valmes of u.n:lralned modulus, drained modulus, umlralmed shear strength amd coefficient of consolidatiom are determined in a straightfc~ard test ~a~ecedure. The furdamental mature of the test as well as preliminary results suggest that e ~ valuable data may be obtained at relatively low cost. Auth.
Texture, structure, composition
and dmsity 82~o~8 C ~
AND EDGE EFFECTS IN AREAL AND LINE TRA~ SAMPLING OF ROCK JOINT TRACES i Laelett, G M J I ~ Ass Math Geol# VI~, N2, April 1962,
lm_2~-l~) Reviews techniques for correcting far bias when Inecm~xlete observations fo~nn part of a data set. The ~w~larities and differences between biases due t o @mmmcrlng and edge effects are emphasised, the lat%e~ Being of i ~ a n c e when the dlstributicm ~f ~oint traces is estimated from an expos~s~e. A mew technique for ar~lysing line transect data is presented, and a new analysis of Im~bl~hed ~ata on Joint trace l e r ~ s is given. Auth. 32 refs.
825019 SOME
EFFECTS OF COMPACTION AND GE~0GICAL TIME ON THE PORE PAR~,'E~S OF ARGILLACEOUS ROCKS Borst, R L Sedimentology, V29, N2, April 1982, P291-298
Graphical statistics have been applied to the pare-size distribution curves of argillaceous rocks to characterize the charges in pore parameters that result from compaction and geological time. The most striking characteristic of recently deposited sediment is the high variability in mean pore size and in the sorting and skewness of the pore system. The mean pore size of shales decreases with increasing compaction and approaches a limiting value of about 3.Snm at depth. Sediments buried to a depth of 500m or less exhibit a porosity range of 40-85 per cent: below 50Ore, porosity decreases linearly with burial depth. No correlation exists between the surface area of shale pore systems and depth of btmial, geological age, and the pore parameters mean pore size, sorting, and skewness.
825020
PLUMMRT BAI~NCE - A I~Y~ENTIAL TOOL FOR SUBSIEVE PARTICLE SIZE ANALYSIS. TECHNICAL NOTE NagaraJ, T S; Sivapullalah, P V Geotech Test J, V4, N1, March 1981 , PB6-40 An experimental investigation was carried out to compare the plummet balance method with two other methods of subsieve particle size ar~ysis, the pipette and the hydrometer methods, and to identify critical factors to be considered when using this method. The experiments were carried out on kaolinite and fire clay. Results i:~licate that for a plummet immersion of 20cm the particle size distribution wottld be similar to that obtained by the hydrometer and pipette methods.
Attempts to relate the closeness of packing of ions expressed as the cation packing index (k-value) to the physical ~roperties density amd seismic velocity. The study relates to the deteTruination of the mineralogy of the lithosphere from the earth's surface. 825022 RELATIONSHIPS BEI'w-EEN THE P~.'I'KOFHYSICALPROf."RTIES DENSITY, SEISMIC VELOCITY, HEAT GENERATION, AND MINERALOGICAL CONSTITUTION Rybach, L; Buntebarth, G Earth Planet Sci Lett, V57, N2, Feb 1982,
P367-376 Mineralogical constitution is represented by the cation fraction (k-value). The paper reports density, P wave velocity and heat generation measurements on i00 crystalline rocks (granophyres, granites, granodic~ites, tonelites, diorites, gabbros, amphibolites, hc~nblendites, pyroxenltes, ultrabasic rocks) and establishment of relationships by regression analysis.
Fracture processes 825023 ACOUSTIC EMISSION STUDY OF MICROFRACTURING DURING THE CYCLIC LOADING OF WESTERLY GRANITE Sondergeld, C H; Estey~ L H J Geophys Res, V86, N ~ , I0 April 1981, P2915-2924 A rectamgular prism of Westerly granite was defc~ned in a umiaxial cycling experiment. Acoustic emission activity was recorded usirg eight transducers in real time. Hypocenters of ll6 events were determir~d using a standard least squares approach. The cumulative distribution of hypocenters documents the strongly anisotroplc development of dilatancy in Westerly granite. Volumetric strain, differential stress, acoustic emission event rate 3 amd cumulative numbers were continuously measured during the experiment. The c~nulative number of events per cycle generally decreased with the number of cycles. The majority of events occurred upon loading. Those that occurred during unloading were few in n ~ e r and not as systematically related to stress.
82502~ STUDY
ON THE TIME-DEPENDENT MICROFRACTURING AND STRENGTH OF OSHIMA GRANITE Sano, O; T~rada, M; Ehara, S Tectonophysics, vS~, N2-4, 20 April 1982 , PB43-362
Unlaxial compression tests wh~re axial strain rate or dilatant volumetric strain rate was kept constant were carried out using a servo-controlled hydraulic testir~ machine. A theory based on the asst~nption of re-diatribution of ~re-existimg microcracks due tc subcritical crack growth was examined, amd theoretical results were found to agree well with experiment. The acoustic emissions were monitored as a measure of crack growth.
Strength characteristics 825021 DENSITY AND SEIS~-IC VELOCITY IN RELATION TO MI~OGICAL CONSTITUTION BASED ON AN IONIC MODEL FOR MIN~qALS Buntebarth, G Earth Planet Sci Lett, V57, N2, Feb 1982,
P358-366
It.M.M.S. 19/5--D
See also: 82504% 825209 825025 INCREMENTAL LOADING DEVICE FOR STRESS PATH AND STRENGTH TESTING OF SOILS NagaraJ~ T S; Murthy, M K; Sridharan, A