Now showing items 1-10 of 69
Duration and severity of Medieval drought in the Lake Tahoe Basin
(Elsevier B.V., 2001-09-16)
Droughts in the western U.S. in the past 200 years are small compared to several megadroughts that occurred during Medieval times. We reconstruct duration and magnitude of extreme droughts in the northern Sierra Nevada ...
Modeling sulfate reduction in methane hydrate-bearing continental margin sediments : does a sulfate-methane transition require anaerobic oxidation of methane?
(American Geophysical Union, 2011-07-12)
The sulfate-methane transition (SMT), a biogeochemical zone where sulfate and methane are metabolized, is commonly observed at shallow depths (1–30 mbsf) in methane-bearing marine sediments. Two processes consume sulfate ...
Correction to “Elastic wave speeds and moduli in polycrystalline ice Ih, sI methane hydrate, and sII methane-ethane hydrate”
(American Geophysical Union, 2009-04-10)
Gas and gas hydrate distribution around seafloor seeps in Mississippi Canyon, Northern Gulf of Mexico, using multi-resolution seismic imagery
(Elsevier B.V., 2008-05-10)
To determine the impact of seeps and focused flow on the occurrence of shallow gas hydrates, several seafloor mounds in the Atwater Valley lease area of the Gulf of Mexico were surveyed with a wide range of seismic ...
NOAA/West Coast and Alaska Tsunami Warning Center response criteria
(Tsunami Society, 2009)
West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakes occurring in the Atlantic and Caribbean basins are presented. Initial warning center decisions are based on an earthquake’s location, ...
Current subsidence rates due to compaction of Holocene sediments in southern Louisiana
(American Geophysical Union, 2006-06-14)
Relative contributions of geologic and anthropogenic processes to subsidence of southern Louisiana are vigorously debated. Of these, shallow sediment compaction is often considered dominant, although this has never been ...
Volume change associated with formation and dissociation of hydrate in sediment
(American Geophysical Union, 2010-03-11)
Gas hydrate formation and dissociation in sediments are accompanied by changes in the bulk volume of the sediment and can lead to changes in sediment properties, loss of integrity for boreholes, and possibly regional ...
Extension in Mona Passage, Northeast Caribbean
(Elsevier B.V., 2010-07-15)
As shown by the recent Mw 7.0 Haiti earthquake, intra-arc deformation, which accompanies the subduction process, can present seismic and tsunami hazards to nearby islands. Spatially-limited diffuse tectonic deformation ...
Elastic wave speeds and moduli in polycrystalline ice Ih, sI methane hydrate, and sII methane-ethane hydrate
(American Geophysical Union, 2009-02-27)
We used ultrasonic pulse transmission to measure compressional, P, and shear, S, wave speeds in laboratory-formed polycrystalline ice Ih, sI methane hydrate, and sII methane-ethane hydrate. From the wave speed's linear ...
Finite-frequency wave propagation through outer rise fault zones and seismic measurements of upper mantle hydration
(John Wiley & Sons, 2016-08-14)
Effects of serpentine-filled fault zones on seismic wave propagation in the upper mantle at the outer rise of subduction zones are evaluated using acoustic wave propagation models. Modeled wave speeds depend on azimuth, ...