Now showing items 1-10 of 72
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 ...
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 ...
Glacial morphology and depositional sequences of the Antarctic continental shelf
(Geological Society of America, 1995-07)
We propose a simple model for the unusual depositional sequences and morphology of the Antarctic continental shelf. Our model considers the regional stratal geometry and the reversed morphology of the Antarctic continental ...
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)
Estimating pore-space gas hydrate saturations from well log acoustic data
(American Geophysical Union, 2008-07-09)
Relating pore-space gas hydrate saturation to sonic velocity data is important for remotely estimating gas hydrate concentration in sediment. In the present study, sonic velocities of gas hydrate–bearing sands are modeled ...
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 ...
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, ...
Magnetic character of a large continental transform : an aeromagnetic survey of the Dead Sea Fault
(American Geophysical Union, 2007-07-13)
New high-resolution airborne magnetic (HRAM) data along a 120-km-long section of the Dead Sea Transform in southern Jordan and Israel shed light on the shallow structure of the fault zone and on the kinematics of the plate ...
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 ...