Shear and tension hydraulic fractures in low permeability rocks
P. Solberg, D. Lockner, J. Byerlee
1977, Pure and Applied Geophysics PAGEOPH (115) 191-198
Laboratory hydrofracture experiments were performed on triaxially stressed specimens of oil shale and low-permeability granite. The results show that either shear or tension fractures could develop depending on the level of differentials stress, even in specimens containing preexisting fractures. With 1 kb of confining pressure and differential stress greater than...
Earthquake stress drops, ambient tectonic stresses and stresses that drive plate motions
Thomas C. Hanks
1977, Pure and Applied Geophysics PAGEOPH (115) 441-458
A variety of geophysical observations suggests that the upper portion of the lithosphere, herein referred to as the elastic plate, has long-term material properties and frictional strength significantly greater than the lower lithosphere. If the average frictional stress along the non-ridge margin of the elastic plate is of the order...
Examination of the Chayes-Kruskal procedure for testing correlations between proportions
J.O. Kork
1977, Mathematical Geology (9) 543-562
The Chayes-Kruskal procedure for testing correlations between proportions uses a linear approximation to the actual closure transformation to provide a null value, pij, against which an observed closed correlation coefficient, rij, can be tested. It has been suggested that a significant difference between pij and rij would indicate a nonzero...
Abundance coefficients, a new method for measuring microorganism relative abundance
R. M. Forester
1977, Mathematical Geology (9) 619-633
A new method of measuring the relative abundance of microorganisms by using a set of interrelated coefficients, termed 'abundance coefficients' or 'AC', is proposed. These coefficients provide a means of recording abundance for geometric density categories, and each density measurement represents an approximation of the Poisson parameter ??t. The AC...
Oxygen and hydrogen isotope compositions as indicators of granite genesis in the New England Batholith, Australia
J. R. O’Neil, S.E. Shaw, R.H. Flood
1977, Contributions to Mineralogy and Petrology (62) 313-328
Oxygen and hydrogen isotope studies of a number of granite suites and mineral separates from the New England Batholith indicate that ??O18 can be used to discriminate the major granite protoliths. The granite suites previously subdivided on the basis of mineralogical and geochemical criteria into S-type (sedimentary) and I-type (igneous)...
The thermal and deformational history of apollo 15418, A partly shock-melted lunar breccia
Gordon L. Nord Jr., J.M. Christie, J.S. Lally, A.H. Heuer
1977, The Moon (17) 217-231
A thermal and mechanical history of lunar gabbroic anorthosite 15418 (1140g) has been deduced from petrographic examination of both exterior and interior thin sections and electron microprobe analysis and transmission electron microscopy of interior thin sections. We suggest that the rock underwent two major shock events - an early brecciation...
Fluid inclusion geothermometry
C.G. Cunningham
1977, Geologische Rundschau (66) 1-9
Fluid inclusions trapped within crystals either during growth or at a later time provide many clues to the histories of rocks and ores. Estimates of fluid-inclusion homogenization temperature and density can be obtained using a petrographic microscope with thin sections, and they can be refined using heating and freezing stages....
The Aristarchus-Harbinger region of the moon: Surface geology and history from recent remote-sensing observations
S.H. Zisk, C. A. Hodges, H. J. Moore, R.W. Shorthill, T.W. Thompson, E. A. Whitaker, D.E. Wilhelms
1977, The Moon (17) 59-99
The region including the Aristarchus Plateau and Montes Harbinger is probably the most diverse, geologically, of any area of comparble size on the Moon. This part of the northwest quadrant of the lunar near side includes unique dark mantling material; both the densest concentration and the largest of the sinuous...
Entropy, materials, and posterity
P. Cloud
1977, Geologische Rundschau (66) 678-696
Materials and energy are the interdependent feedstocks of economic systems, and thermodynamics is their moderator. It costs energy to transform the dispersed minerals of Earth's crust into ordered materials and structures. And it costs materials to collect and focus the energy to perform work - be it from solar, fossil...
Voyager imaging experiment
B.A. Smith, G.A. Briggs, G. E. Danielson, A.F. Cook II, M. E. Davies, G.E. Hunt, H. Masursky, L.A. Soderblom, T.C. Owen, C. Sagan, V.E. Suomi
1977, Space Science Reviews (21) 103-127
The overall objective of this experiment is exploratory reconnaissance of Jupiter, Saturn, their satellites, and Saturn's rings. Such reconnaissance, at resolutions and phase angles unobtainable from Earth, can be expected to provide much new data relevant to the atmospheric and/or surface properties of these bodies. The experiment also has the...
Target intersection probabilities for parallel-line and continuous-grid types of search
R.B. McCammon
1977, Journal of the International Association for Mathematical Geology (9) 369-382
The expressions for calculating the probability of intersection of hidden targets of different sizes and shapes for parallel-line and continuous-grid types of search can be formulated by vsing the concept of conditional probability. When the prior probability of the orientation of a widden target is represented by a uniform distribution,...
10. The surface and interior of venus
H. Masursky, W.M. Kaula, G.E. McGill, G.H. Pettengill, R.J. Phillips, C.T. Russell, G. Schubert, I.I. Shapiro
1977, Space Science Reviews (20) 431-449
Present ideas about the surface and interior of Venus are based on data obtained from (1) Earth-based radio and radar: temperature, rotation, shape, and topography; (2) fly-by and orbiting spacecraft: gravity and magnetic fields; and (3) landers: winds, local structure, gamma radiation. Surface features, including large basins, crater-like depressions, and...
New geochronologic and palaeomagnetic data for the hominid-bearing Hadar Formation of Ethiopia
J.L. Aronson, T.J. Schmitt, R.C. Walter, M. Taieb, J.J. Tiercelin, D.C. Johanson, C. W. Naeser, A.E.M. Nairn
1977, Nature (267) 323-327
A 2.6 Myr K/Ar age has been derived for a primary unreworked tuff high in the hominid-bearing Hadar Formation (Kada Hadar Member), stratigraphically above all the important fossil finds. A 2.6 Myr fission track age has been derived on zircons from this tuff. New K/Ar results on the Kadada Moumou...
Rapidly-formed ferromanganese deposit from the eastern Pacific Hess Deep
W. C. Burnett, D.Z. Piper
1977, Nature (265) 596-600
A thick ferromanganese deposit encrusting fresh basaltic glass has been dredged from the Hess Deep in the eastern Pacific. Contiguous layers within the Fe-Mn crust have been analysed for uranium-series isotopes and metal contents. The rate of accumulation of the deposit, based on the decline of uranium-unsupported 230Th, is calculated...
Physiological characteristics of mercury uptake by two estuarine species
S. N. Luoma
1977, Marine Biology (41) 269-273
Rapid uptake and slow loss of Hg will result from short exposures of some organisms to this metal, due to the transformation of Hg to a slowly exchanging form within the organisms. The extent of the difference between exposure time and depuration time will depend upon the rate of transformation...
A digital file of the lunar normal Albedo
R.L. Wildey
1977, The Moon (16) 231-277
A digital file of the normal albedo of the Moon has been produced at a resolution of about 1/550 of a lunar diameter (about 6.3 km). The file was produced from five photographs taken with the 61-cm reflector of the Northern Arizona University Astrophysical Observatory. No mosaicking was necessary. Spatial...
Application of Sr and O isotope relations to the petrogenesis of the alkaline rocks of the Red Hill complex, New Hampshire, USA
K.A. Foland, I. Friedman
1977, Contributions to Mineralogy and Petrology (65) 213-225
The Red Hill ring complex in central New Hampshire is composed of apparently cogenetic syenites, nepheline-sodalite syenite, and granite. The ages and petrogenetic relations among five of the six recognized units have been investigated by rubidiumstrontium and oxygen isotope analysis of whole rocks and separated minerals. Whole-rock samples from three...
Distribution of pollutants from a new paper plant in southern Lake Champlain, Vermont and New York
D.L. Mason, D. W. Folger, R.S. Haupt, R.R. McGirr, W.H. Hoyt
1977, Environmental Geology (1) 341-347
From November of 1973 to May of 1974, 15 arrays of sediment traps were placed along 33 km of southern Lake Champlain to sample the distribution of effluent from a large paper plant located on the western shore which had commenced operation in 1971. In the arrays located near the...
Note on the chromatographic analyses of marine polyunsaturated fatty acids
D.M. Schultz, J.G. Quinn
1977, Marine Biology (40) 117-120
Gas-liquid chromatography was used to study the effects of saponification/methylation and thin-layer chromatographic isolation on the analyses of polyunsaturated fatty acids. Using selected procedures, the qualitative and quantitative distribution of these acids in marine organisms can be determined with a high degree of accuracy. ?? 1977 Springer-Verlag....
Stable isotopes in mineralogy
J. R. O’Neil
1977, Physics and Chemistry of Minerals (2) 105-123
Stable isotope fractionations between minerals are functions of the fundamental vibrational frequencies of the minerals and therefore bear on several topics of mineralogical interest. Isotopic compositions of the elements H, C, O, Si, and S can now be determined routinely in almost any mineral. A summary has been made of...
Survey of trace elements in coals and coal-related materials by neutron activation analysis
R.R. Ruch, R.A. Cahill, J.K. Frost, L.R. Camp, H.J. Gluskoter
1977, Journal of Radioanalytical Chemistry (38) 415-424
Utilizing primarily instrumental neutron activation analysis (INAA) and other analytical methods as many as 61 elements were quantitatively surveyed in 170 U.S. whole coals, 70 washed coals, and 40 bench samples. Data on areal and vertical distributions in various regions were obtained along with extensive information on the mode of...
Application of epithermal neutron activation in multielement analysis of silicate rocks employing both coaxial Ge(Li) and low energy photon detector systems
P. A. Baedecker, J.J. Rowe, E. Steinnes
1977, Journal of Radioanalytical Chemistry (40) 115-146
The instrumental activation analysis of silicate rocks using epithermal neutrons has been studied using both high resolution coaxial Ge(Li) detectors and low energy photon detectors, and applied to the determination of 23 elements in eight new U.S.G.S. standard rocks. The analytical use X-ray peaks associated with electron capture or internal...
The precision and accuracy of iterative and non-iterative methods of photopeak integration in activation analysis, with particular reference to the analysis of multiplets
P. A. Baedecker
1977, Journal of Radioanalytical Chemistry (39) 239-254
The relative precisions obtainable using two digital methods, and three iterative least squares fitting procedures of photopeak integration have been compared empirically using 12 replicate counts of a test sample with 14 photopeaks of varying intensity. The accuracy by which the various iterative fitting methods could analyse synthetic doublets has...
Preliminary stress measurements in central California using the hydraulic fracturing technique
Mark D. Zoback, J. H. Healy, J.C. Roller
1977, Pure and Applied Geophysics PAGEOPH (115) 135-152
Use of the hydraulic fracturing technique for determining in situ stress is reviewed, and stress measurements in wells near the towns of Livermore, San Ardo, and Menlo Park, California are described in detail. In the Livermore well, four measurements at depths between 110 and 155 m indicate that the least...
A crystal-chemical classification of borate structures with emphasis on hydrated borates
C. L. Christ, J. R. Clark
1977, Physics and Chemistry of Minerals (2) 59-87
The rules governing formation of hydrated borate polyanions that were proposed by C.L. Christ in 1960 are critically reviewed and new rules added on the basis of recent crystal structure determinations. Principles and classifications previously published by others are also critically reviewed briefly. The fundamental building blocks from which borate...
