Publications
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Recording and processing procedures for multi-channel seismic-reflection data collected in the western Ross Sea, Antarctica
During 1984, over 2300 km of multichannel seismic-reflection data were recorded by the U.S. Geological Survey in the western Ross Sea and Iselin Bank regions. A temporary loss and sinking of the streamer led to increasing the streamer tow depth to 20 m, which resulted in some attenuation of frequencies in the 30-50 Hz range but no significant difference in resolution of the stacked data. Severe
Authors
Shawn V. Dadisman, Holly F. Ryan, Dennis M. Mann
Ionic conductivity of quartz: DC time dependence and transition in charge carriers
The time dependence of DC electrical conductivity in the c-axis direction of quartz can be accounted for by a transition in charge carriers from interstitial alkali impurities to interstitial H. The diffusive transport rates of Li, Na, and K are rapid parallel to c and have been shown to be responsible for the highly anisotropic electrical conductivity measured at short times. With increasing time
Authors
A. K. Kronenberg, Stephen H. Kirby
Inelastic properties of ice Ih at low temperatures and high pressures
The aim of our research programme is to explore the rheological behavior of H2O ices under conditions appropriate to the interiors of the icy satellites of the outer planets in order to give insight into their deformation. To this end, we have performed over 100 constant-strain-rate compression tests at pressures to 500 MPa and temperatures as low as 77 K. At P > 30 MPa, ice Ih fails by a shear in
Authors
Stephen H. Kirby, William B. Durham, M.L. Beeman, H.C. Heard
Inelastic properties of several high pressure crystalline phases of H2O: Ices II, III, and V
We have performed deformation experiments on cylinders of polycrystalline H2O at temperatures from 178 to 257 K at pressures to 500 MPa in the stability fields of ices II, III, and V. Ice II is the strongest of the phases, having a strength under laboratory conditions roughly comparable to that of ice Ih. Ice V is somewhat weaker than ice II. Ice III is extremely weak and over geologic times must
Authors
William B. Durham, Stephen H. Kirby, H. C. Heard, Laura A. Stern
Correction to “Rheology of the lithosphere: Selected topics”
No abstract available.
Authors
Stephen H. Kirby, A. K. Kronenberg
I. Thermal evolution of Ganymede and implications for surface features. II. Magnetohydrodynamic constraints on deep zonal flow in the giant planets. III. A fast finite-element algorithm for two-dimensional photoclinometry
The work is divided into three independent papers:PAPER I:Thermal evolution models are presented for Ganymede, assuming a mostly differentiated initial state of a water ocean overlying a rock layer. The only heat sources are assumed to be primordial heat (provided by accretion) and the long-lived radiogenic heat sources in the rock component. As Ganymede cools, the ocean thins, and two ice layers
Authors
Randolph L. Kirk
Snow and ice studies by thematic mapper and multispectral scanner Landsat images
Digitally enhanced Landsat Thematic Mapper (TM) images of Antarctica reveal snow and ice features to a detail never seen before in satellite images. The six TM reflective spectral bands have a nominal spatial resolution of 30 m, compared to 80 m for the Multispectral Scanner (MSS). TM bands 2–4 are similar to the MSS bands. TM infra-red bands 5 and 7 discriminate better between clouds and snow tha
Authors
Olav Orheim, Baerbel K. Lucchitta
Thermal evolution of a differentiated Ganymede and implications for surface features
Thermal evolution models are presented for Ganymede, assuming a mostly differentiated initial state of a water ocean overlying a rock layer. The only heat sources are assumed to be primordial heat (provided by accretion) and the long-lived radiogenic heat sources in the rock component. As Ganymede cools, the ocean thins, and two ice layers develop, one above composed of ice I, and the other below
Authors
Randolph L. Kirk, David J. Stevenson
Hydromagnetic constraints on deep zonal flows in the giant planets
The observed zonal flows of the giant planets will, if they penetrate below the visible atmosphere, interact significantly with the planetary magnetic field outside the metallized core. The appropriate measure of this interaction is the Chandrasekhar number Q = H^2 /4πρνα^2 λ (H = radial component of the magnetic field, ν = eddy viscosity, λ = magnetic diffusivity, α^-1 = length scale on which λ v
Authors
Randolph L. Kirk, David J. Stevenson
Characteristics of anelastic reflection-refraction coefficients with implications for calculation of synthetic seismograms
No abstract available.
Authors
Roger D. Borcherdt
On the aftershock sequence of the earthquake of January 31, 1986 in northeastern Ohio; effects of bandwidth and local geology on observed high-frequency ground motion
No abstract available.
Authors
Roger D. Borcherdt, G. Glassmoyer
Passive margins: U.S. Geological Survey Line 19 across the Georges Bank basin
Georges Bank is a shallow part of the Atlantic continental shelf southeast of New England (Emery and Uchupi, 1972, 1984). This bank, however, is merely the upper surface of several sedimentary basins overlying a block-faulted basement of igneous and metamorphic crystalline rock. Sedimentary rock forms a seaward-thickening cover that has accumulated in one main depocenter and several ancillary depr
Authors
Kim D. Klitgord, John S. Schlee, John A. Grow