Publications
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IPOD-USGS multichannel seismic reflection profile from Cape Hatteras to the Mid-Atlantic Ridge
A 3,400-km-long multichannel seismic-reflection profile from Cape Hatteras to the Mid-Atlantic Ridge was acquired commercially under contract to the National Science Foundation and the U.S. Geological Survey. These data show evidence for massive erosion of the continental slope, diapirs at the base of the continental slope, and mantle reflections beneath the Hatteras Abyssal Plain.
Authors
John A. Grow, Rudi G. Markl
Pleistocene barrier bar seaward of ooid shoal complex near Miami, Florida
An ooid sand barrier bar of Pleistocene age was deposited along the seaward side of an ooid shoal complex southwest of Miami, Florida. The bar is 35 km long, about 0.8 km wide, elongate parallel with the trend of the ooid shoal complex and perpendicular to channels between individual shoals. A depression 1.6 km wide, interpreted as a back-barrier channel, isolates the bar from the ooid shoals. Dur
Authors
Robert B. Halley, Shinn Shinn, J. Harold Hudson, Barbara H. Lidz
The effects of the α‐β phase transformation on the creep properties of hydrolytically‐weakened synthetic quartz
Nine rectangular prisms of hydro‐thermally‐grown synthetic quartz crystals with 900 atomic ppm H+ were loaded in compression at 1400 bars stress and temperatures between 403 and 764°C. The a and c directions were at 45° to the compression direction, and the slip system appears to operate over the entire range of temperatures. The strain vs. time curves were sigmoidal in shape; an incubation stage
Authors
Stephen H. Kirby
Mechanical twinning in diopside Ca(Mg,Fe)Si2O6: Structural mechanism and associated crystal defects
iopside twins mechanically on two planes, (100) and (001), and the associated macroscopic twinning strains are identical (Raleigh and Talbot, 1967). An analysis based on crystal structural arguments predicts that both twin mechanisms involve shearing of the (100) octahedral layers (containing Ca2+, Mg2+ and Fe2+ ions) by a magnitude of c/2. Small adjustments or shuffles occur in the adjacent layer
Authors
Stephen H. Kirby, J.M. Christie
Migration of anthropogenically induced trace metals (barium and lead) in a continental shelf environment
No abstract available.
Authors
Charles W. Holmes, E. Ann Martin, Herbert G. Stewart
Coastal processes and morphology of the Bering Sea coast of Alaska
No abstract available.
Authors
A. H. Sallenger, R. Hunter, J. R. Dingler
Topographic control and accumulation rate of some Holocene coral reefs: south Florida and Dry Tortugas
Core drilling and examination of underwater excavation on 6 reef sites in south Florida and Dry Tortugas revealed that underlying topography is the major factor controlling reef morphology. Carbon-14 dating on coral recovered from cores enables calculation of accumulation rates. Accumulation rates were found to range from 0.38 m/1000 years in thin Holocene reefs to as much as 4.85 m/1000 years in
Authors
E.A. Shinn, J.H. Hudson, R. B. Halley, B. H. Lidz
Limestone compaction: an enigma
Compression of an undisturbed carbonate sediment core under a pressure of 556 kg/cm2 produced a “rock” with sedimentary structures similar to typical ancient fine-grained limestones. Surprisingly, shells, foraminifera, and other fossils were not noticeably crushed, which indicates that absence of crushed fossils in ancient limestones can no longer be considered evidence that limestones do not comp
Authors
Eugene A. Shinn, Robert B. Halley, J. Harold Hudson, Barbara H. Lidz
Topography, structure, and mare ridges in southern Mare Imbrium and northern Oceanus Procellarum
The gross topography in southern Mare Imbrium and northern Oceanus Procellarum correlates with the buried structure and deposits of the Imbrium Basin and its rim, and many of the mare slopes may be depositional and reflect the pre-existing major features of the basin. Post-depositional, local distortion of the mare surface, however, is present and in many places associated with mare ridges. Many m
Authors
Baerbel K. Lucchitta
Crater clusters and light mantle at the Apollo 17 site: A result of secondary impact from Tycho
The morphologies of Tycho secondary craters and their ejecta deposits were studied using full-Moon, Lunar-Orbiter, and Apollo panoramic photographs. These data were compared with similar data for the secondary craters and light mantle of the Apollo 17 landing site. The results indicate that (1) the central crater cluster and the light mantle can be attributed to Tycho, (2) the dominant mechanism f
Authors
Baerbel K. Lucchitta