Publications
Filter Total Items: 7611
Historical shoreline mapping (I): improving techniques and reducing positioning errors Historical shoreline mapping (I): improving techniques and reducing positioning errors
A critical need exists among coastal researchers and policy-makers for a precise method to obtain shoreline positions from historical maps and aerial photographs. A number of methods that vary widely in approach and accuracy have been developed to meet this need. None of the existing methods, however, address the entire range of cartographic and photogrammetric techniques required for...
Authors
E. Robert Thieler, William W. Danforth
Development of lava tubes in the light of observations at Mauna Ulu, Kilauea Volcano, Hawaii Development of lava tubes in the light of observations at Mauna Ulu, Kilauea Volcano, Hawaii
During the 1969-1974 Mauna Ulu eruption on Kilauea's upper east rift zone, lava tubes were observed to develop by four principal processes: (1) flat, rooted crusts grew across streams within confined channels; (2) overflows and spatter accreted to levees to build arched roofs across streams; (3) plates of solidified crust floating downstream coalesced to form a roof; and (4) pahoehoe...
Authors
D. W. Peterson, R. T. Holcomb, R.I. Tilling, R.L. Christiansen
Hydrothermal systems of the Cascade Range, north-central Oregon Hydrothermal systems of the Cascade Range, north-central Oregon
Quaternary volcanoes of the Cascade Range form a 1,200- kilometer-long arc that extends from southern British Columbia to northern California. The section of the Cascade Range volcanic arc in central Oregon is characterized by relatively high Quaternary volcanic extrusion rates and hot-spring discharge rates. Stableisotope data and measurements of hot-spring heat discharge indicate that...
Authors
S. E. Ingebritsen, Robert H. Mariner, David R. Sherrod
Meteoroid mayhem in Ole Virginny: Source of the North American tektite strewn field Meteoroid mayhem in Ole Virginny: Source of the North American tektite strewn field
New seismic reflection data from Chesapeake Bay reveal a buried, 85-km-wide, 1.5-2.0-km-deep, peak-ring impact crater, carved through upper Eocene to Lower Cretaceous sedimentary strata and into underlying pre-Mesozoic crystalline basement rocks. A polymictic, late Eocene impact breccia, composed mainly of locally derived sedimentary debris (determined from four continuous cores)...
Authors
C. Wylie Poag, David S. Powars, Lawrence J. Poppe, Robert B. Mixon
Submarine canyon initiation by downslope-eroding sediment flows: Evidence in late Cenozoic strata on the New Jersey continental slope Submarine canyon initiation by downslope-eroding sediment flows: Evidence in late Cenozoic strata on the New Jersey continental slope
Multibeam bathymetry and seismic reflection profiles of the New Jersey continental slope reveal a series of abandoned and now-buried submarine canyons that have apparently influenced the development of modern canyons. The buried canyons are infilled along nine slope-wide unconformities separating upper-middle Miocene to Pleistocene sediments that thin downslope. Canyons infilled during...
Authors
Lincoln F. Pratson, William B. F. Ryan, Gregory S. Mountain, David C. Twichell
The role of magmas in the formation of hydrothermal ore deposits The role of magmas in the formation of hydrothermal ore deposits
Magmatic fluids, both vapour and hypersaline liquid, are a primary source of many components in hydrothermal ore deposits formed in volcanic arcs. These components, including metals and their ligands, become concentrated in magmas in various ways from various sources, including subducted oceanic crust. Leaching of rocks also contributes components to the hydrothermal fluid—a process...
Authors
Jeffrey W. Hedenquist, Jacob B. Lowenstern
Six years of change in Lake Nyos, Cameroon, yield clues to the past and cautions for the future Six years of change in Lake Nyos, Cameroon, yield clues to the past and cautions for the future
The catastrophic release of gas from Lake Nyos, Cameroon, in 1986 caused substantial but incomplete mixing of the stratified water column. The post-release evolution of water-column structure has been monitored through April 1992. Changes began immediately after the event as rainfall and inflow brought dilute fluid into the surface layer. Inflow and surface mixing have gradually deepened...
Authors
William C. Evans, L. D. White, M. L. Tuttle, G.W. Kling, G. Tanyileke, R. L. Michel
Quaternary tectonics of Utah with emphasis on earthquake-hazard characterization Quaternary tectonics of Utah with emphasis on earthquake-hazard characterization
This report consolidates and synthesizes information on Quaternary faulting, folding, and volcanism in Utah and characterizes recent tectonic activity throughout the state. The primary purpose is to provide a comprehensive reference on faultspecific seismic sources and surface rupture to facilitate the evaluation of earthquake hazards in Utah. Two 1:500,000-scale maps show Quaternary...
Authors
Suzanne Hecker
Geology and human activity in the Florida Keys Geology and human activity in the Florida Keys
No abstract available.
Authors
Eugene A. Shinn
Proposal for worldwide landslide hazard maps Proposal for worldwide landslide hazard maps
No abstract available.
Authors
E. E. Brabb
Lake Baikal - A touchstone for global change and rift studies Lake Baikal - A touchstone for global change and rift studies
No abstract available.
Authors
Deborah R. Hutchinson, Steve M. Colman
Priorities for landslide mapping during the International Decade of Hazard Reduction Priorities for landslide mapping during the International Decade of Hazard Reduction
No abstract available.
Authors
E. E. Brabb