Skip to main content
U.S. flag

An official website of the United States government

Publications

Filter Total Items: 7497

Morphology of sea-floor landslides on Horizon Guyot: application of steady-state geotechnical analysis Morphology of sea-floor landslides on Horizon Guyot: application of steady-state geotechnical analysis

Mass movement and erosion have been identified on the pelagic sediment cap of Horizon Guyot, a seamount in the Mid-Pacific Mountains. Trends in the size, shape and preservation of bedforms and sediment textural trends on the pelagic cap indicate that bottom-current-generated sediment transport direction is upslope. Slumping of the sediment cap occurred on and that the net bedload...
Authors
R. E. Kayen, W. C. Schwab, H.J. Lee, M.E. Torresan, J.R. Hein, P. J. Quinterno, L.A. Levin

Structures associated with strike-slip faults that bound landslide elements Structures associated with strike-slip faults that bound landslide elements

Large landslides are bounded on their flanks and on elements within the landslides by structures analogous to strike-slip faults. We observed the formation of thwse strike-slip faults and associated structures at two large landslides in central Utah during 1983-1985. The strike-slip faults in landslides are nearly vertical but locally may dip a few degrees toward or away from the moving...
Authors
R. W. Fleming, A. M. Johnson

The competition between thermal contraction and differentiation in the stress history of the Moon The competition between thermal contraction and differentiation in the stress history of the Moon

The scarcity of both extension and compression features on the Moon strongly constrains the history of the lunar radius—to variations of less than ±1 km over the past 3.8 Gyr. This limit has traditionally been interpreted as requiring a delicate balance between thermal contraction of the near‐surface and expansion of a substantial cold interior region. Recent theories of lunar origin (e...
Authors
Randolph L. Kirk, David J. Stevenson

IRIS/USGS plans for upgrading the Global Seismograph Network IRIS/USGS plans for upgrading the Global Seismograph Network

This report has been prepared to provide information to organizations that may be asked to participate in a program to upgrade the global seismographic network. In most cases, the organizations that will be offered new instrumentation by the U.S. Geological Survey currently operate stations in the World-Wide Standardized Seismograph Network (WWSSN) or the Global Digital Seismograph...
Authors
Jon Peterson, Charles R. Hutt

Vertical seismic profiling of Oroville microearthquakes: Velocity spectra and particle motion as a function of depth Vertical seismic profiling of Oroville microearthquakes: Velocity spectra and particle motion as a function of depth

Direct evidence of site distortion of P- and S-wave microearthquake source spectra at Oroville, California, is presented. The data were gathered by placing vertical and three-component seismometers at 90 m intervals in a 500 m borehole through the Cleveland Hill normal fault, on which the 1975, ML = 5.7 Oroville earthquake took place. High-pressure, hydraulic locking mechanisms were used...
Authors
P. E. Malin, J. A. Waller, Roger D. Borcherdt, E. Cranswick, Edward G. Jensen, J. Van Schaak

Friction of ice Friction of ice

The frictional strength of ice seems to be well below that for all other rocks. Triaxial testing of cylinders of pure water ice containing a 45° inclined sawcut, at temperatures of 77 ≤ T ≤ 115 K and confining pressures 0.1 ≤ P ≤ 250 MPa, reveals the frictional laws τ = 0.20 σn + 8.3 MPa for P ≥ 10 MPa and τ = 0.55 σn + 1.0 MPa for P ≤ 5 MPa, where τ and σn are the shear and normal...
Authors
M. L. Beeman, W.B. Durham, Stephen H. Kirby
Was this page helpful?