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Physical Sciences and Mathematics Commons™
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- Antarctica -- Environmental conditions (1)
- Atmospheric circulation -- Central Asia (1)
- Climate -- Research (1)
- Cryoconite -- Analysis (1)
- Explosive volcanic eruptions (1)
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- Extreme environments -- Microbiology (1)
- Glacier mass balance (1)
- Glaciers -- Environmental aspects (1)
- Hydration (1)
- Lava flows -- Viscosity (1)
- Lightning (1)
- Paleoclimatology (1)
- Rheology (1)
- Volcanic ash tuff etc -- Cascade Range (1)
- Volcanic plumes (1)
- Volcanoes -- Environmental aspects (1)
- Weather -- Effect of volcanic eruptions on (1)
Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
Remote Characterization Of Dominant Wavelengths From Surface Folding On Lava Flows Using Lidar And Discrete Fourier Transform Analyses, Nicholas Deardorff, Adam M. Booth, Katharine Cashman
Remote Characterization Of Dominant Wavelengths From Surface Folding On Lava Flows Using Lidar And Discrete Fourier Transform Analyses, Nicholas Deardorff, Adam M. Booth, Katharine Cashman
Geology Faculty Publications and Presentations
Surface folding is common in lava flows of all compositions and is believed to be due to changes in viscosity and flow velocity between the cooling crust and the more fluid flow interior. However, our understanding of the relationship between surface folding and flow rheology is incomplete. In this study we analyze digital terrain models of eight lava flows ranging in composition from basaltic andesite to rhyolite using a discrete Fourier transform analysis to quantitatively determine dominant surface fold wavelengths. Our discrete Fourier transform analyses show that each lava flow has multiple fold generations and that dominant wavelengths are more …
Comparison Of Microbial Communities In The Sediments And Water Columns Of Frozen Cryoconite Holes In The Mcmurdo Dry Valleys, Antarctica, Pacifica Sommers, John L. Darcy, Dorota L. Porazinska, Eli M. S. Gendron, Andrew G. Fountain, Felix Jacob Zamora, Kim Vincent, Kaelin M. Cawley, Adam J. Solon, Lara Vimercati, Jenna Ryder, Steven K. Schmidt
Comparison Of Microbial Communities In The Sediments And Water Columns Of Frozen Cryoconite Holes In The Mcmurdo Dry Valleys, Antarctica, Pacifica Sommers, John L. Darcy, Dorota L. Porazinska, Eli M. S. Gendron, Andrew G. Fountain, Felix Jacob Zamora, Kim Vincent, Kaelin M. Cawley, Adam J. Solon, Lara Vimercati, Jenna Ryder, Steven K. Schmidt
Geology Faculty Publications and Presentations
Although cryoconite holes, sediment-filled melt holes on glacier surfaces, appear small and homogenous, their microbial inhabitants may be spatially partitioned. This partitioning could be particularly important for maintaining biodiversity in holes that remain isolated for many years, such as in Antarctica. We hypothesized that cryoconite holes with greater species richness and biomass should exhibit greater partitioning between the sediments and water, promoting greater biodiversity through spatial niche partitioning. We tested this hypothesis by sampling frozen cryoconite holes along a gradient of biomass and biodiversity in the Taylor Valley, Antarctica, where ice-lidded cryoconite holes are a ubiquitous feature of glaciers. We …
Reanalysis Of The Us Geological Survey Benchmark Glaciers: Long-Term Insight Into Climate Forcing Of Glacier Mass Balance, Shad O’Neel, Christopher Mcneil, Louis Sass, Caitlyn Florentine, Emily Baker, Andrew G. Fountain, Multiple Additional Authors
Reanalysis Of The Us Geological Survey Benchmark Glaciers: Long-Term Insight Into Climate Forcing Of Glacier Mass Balance, Shad O’Neel, Christopher Mcneil, Louis Sass, Caitlyn Florentine, Emily Baker, Andrew G. Fountain, Multiple Additional Authors
Geology Faculty Publications and Presentations
Mountain glaciers integrate climate processes to provide an unmatched signal of regional climate forcing. However, extracting the climate signal via intercomparison of regional glacier mass-balance records can be problematic when methods for extrapolating and calibrating direct glaciological measurements are mixed or inconsistent. To address this problem, we reanalyzed and compared long-term mass-balance records from the US Geological Survey Benchmark Glaciers. These five glaciers span maritime and continental climate regimes of the western United States and Alaska. Each glacier exhibits cumulative mass loss since the mid-20th century, with average rates ranging from −0.58 to −0.30 m w.e. a−1. We produced a …
The Isotopic Composition Of Meteoric Water Along Altitudinal Transects In The Tian Shan Of Central Asia, John Bershaw, Alex R. Lechler
The Isotopic Composition Of Meteoric Water Along Altitudinal Transects In The Tian Shan Of Central Asia, John Bershaw, Alex R. Lechler
Geology Faculty Publications and Presentations
The Tian Shan in Central Asia are a unique mountain range in that they are in the world's most continental location. Seasonal precipitation in the northern Tian Shan is segregated into distinct elevation bands where high elevations receive precipitation primarily during summer and low elevations to the north receive precipitation primarily during the late winter and spring. In this study, we sampled stream water along multiple altitudinal transects to determine the effect unique seasonal patterns of precipitation have on the isotopic composition of surface water. Our results suggest that the northern Tian Shan exhibits an isotopic lapse rate for waters …
Globally Detected Volcanic Lightning And Umbrella Dynamics During The 2014 Eruption Of Kelud, Indonesia, Kirstin A. Hargie, Alexa R. Van Eaton, L. G. Mastin, Robert H. Holzworth, John W. Ewert, Michael Pavolonis
Globally Detected Volcanic Lightning And Umbrella Dynamics During The 2014 Eruption Of Kelud, Indonesia, Kirstin A. Hargie, Alexa R. Van Eaton, L. G. Mastin, Robert H. Holzworth, John W. Ewert, Michael Pavolonis
Geology Faculty Publications and Presentations
Volcanic lightning shows considerable promise as a monitoring and research tool to characterize explosive eruptions. Its key strengths are rapid and remote detection, because the radio signals produced by lightning can propagate thousands of km at the speed of light. Despite these tantalizing properties, the scientific work on volcanic lightning has only recently started gaining momentum. Much more is needed to understand what lightning reveals about the evolution of an eruption in near-real time. Here we examine the timing and energy release of lightning generated by the eruption of Kelud volcano in Indonesia on 13 February 2014, as detected by …
Volcanic Glass As A Proxy For Cenozoic Elevation And Climate In The Cascade Mountains, Oregon, Usa, John Bershaw, Elizabeth J. Cassell, Tessa Boe Carlson, Ashley R. Streig, Martin J. Streck
Volcanic Glass As A Proxy For Cenozoic Elevation And Climate In The Cascade Mountains, Oregon, Usa, John Bershaw, Elizabeth J. Cassell, Tessa Boe Carlson, Ashley R. Streig, Martin J. Streck
Geology Faculty Publications and Presentations
After deposition, volcanic glass hydrates with ambient water, recording the average hydrogen isotope ratio (δD or δ2H) of local meteoric water during the hydration period. Previous researchers have used ancient glass δD values to reconstruct paleotopography and paleoclimate, while others have questioned the long-term reliability of the proxy as a recorder of ancient meteoric water. In this study, we sampled volcanic glasses ranging in age ~33 Ma to(east) side of the Oregon Cascade Mountains. Our results strongly suggest that volcanic glass acquires and preserves δD values that are proportional to the stable isotopic composition of environmental water at the time …