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- Keyword
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- Glacial landforms -- Antarctica (1)
- Glaciers -- Antarctica (1)
- Glaciers -- Speed -- Measurement -- McMurdo Dry Valleys (Antarctica) (1)
- Hot springs -- Yellowstone National Park (1)
- Ice sheets -- Antarctica -- Dynamics (1)
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- Ice streams -- Antarctica (1)
- Interferometry (1)
- Rock glaciers -- Measurement -- McMurdo Dry Valleys (Antarctica) (1)
- Stream measurements -- Columbia River (1)
- Thermophilic microorganisms -- Morphology (1)
- Thermophilic microorganisms -- Yellowstone National Park (1)
- Water quality -- Columbia River (1)
- Publication Type
Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Microbial Composition Of Near-Boiling Silica-Depositing Thermal Springs Throughout Yellowstone National Park, Carrine E. Blank, Sherry L. Cady, Norman R. Pace
Microbial Composition Of Near-Boiling Silica-Depositing Thermal Springs Throughout Yellowstone National Park, Carrine E. Blank, Sherry L. Cady, Norman R. Pace
Geology Faculty Publications and Presentations
The extent of hyperthermophilic microbial diversity associated with siliceous sinter (geyserite) was characterized in seven near-boiling silica-depositing springs throughout Yellowstone National Park using environmental PCR amplification of small-subunit rRNA genes (SSU rDNA), large-subunit rDNA, and the internal transcribed spacer (ITS). We found that Thermocrinis ruber, a member of the order Aquificales, is ubiquitous, an indication that primary production in these springs is driven by hydrogen oxidation. Several other lineages with no known close relatives were identified that branch among the hyperthermophilic bacteria. Although they all branch deep in the bacterial tree, the precise phylogenetic placement of many of these lineages …
Rock Glacier Surface Motion In Beacon Valley, Antarctica, From Synthetic-Aperture Radar Interferometry, Andrew G. Fountain, Eric Rignot, Bernard Hallet
Rock Glacier Surface Motion In Beacon Valley, Antarctica, From Synthetic-Aperture Radar Interferometry, Andrew G. Fountain, Eric Rignot, Bernard Hallet
Geology Faculty Publications and Presentations
We present radar interferograms of rock glaciers in the Beacon Valley sector of the McMurdo Dry Valleys, in East Antarctica, as part of a comprehensive study of surface processes in the area. Due to the relative absence of net precipitation (snow) in this region and the stability of the surface, the rock glaciers maintain excellent coherence of the radar returns over several years. As a result, we obtain a spatially continuous surface velocity field with a precision of fractions of a millimeter per year. On distinct rock glaciers entering Beacon Valley, we find coherent velocity patterns, with peak velocities approaching …
Force Balance Along An Inland Tributary And Onset To Ice Stream D, West Antarctica, Stephen F. Price, R. A. Bindschadler, Christina L. Hulbe, Donald D. Blankenship
Force Balance Along An Inland Tributary And Onset To Ice Stream D, West Antarctica, Stephen F. Price, R. A. Bindschadler, Christina L. Hulbe, Donald D. Blankenship
Geology Faculty Publications and Presentations
The transition from inland- to streaming-style ice flow near to and upstream from the onset to Ice Stream D, West Antarctica, is investigated using the force- balance technique. Basal drag provides the majority of the flow resistance over the study area but is substantially modified by non-local stress gradients. Lateral drag increases with distance downstream, balancing ~50-100% of the driving stress at the onset. Longitudinal stress gradients (LSG) are also found to be significant, an observation that distinguishes ice flow in this region from the inland- and streaming-flow regimes that bound it, in which LSG are usually negligible. LSG decrease …
In Situ Hydraulic Testing And Water Quality Sampling In The Hyporheic Zone Of The Columbia River, Hanford Reach, Washington, Evan V. Arntzen
In Situ Hydraulic Testing And Water Quality Sampling In The Hyporheic Zone Of The Columbia River, Hanford Reach, Washington, Evan V. Arntzen
Dissertations and Theses
Several chemical and radiological contaminants are present in an unconfined aquifer underlying the U.S. Department of Energy's Hanford Site in southeast Washington State. Hexavalent chromium [Cr(VI)], previously used as an anticorrosive in plutonium production reactors on the shoreline of the Columbia River, is of particular concern because of its conservative nature, toxicity to humans and aquatic life, and proximity to protected salmon spawning habitat. Hydrogeologic data are abundant from the unconfined aquifer, but are lacking from the hyporheic zone through which Cr(VI) is transported into the river. A hydrogeologic study was conducted near one known Cr(VI) plume to determine the …