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Articles 151 - 180 of 965
Full-Text Articles in Earth Sciences
Phosphorus Cycling In Tropical Carbonate Sediment-Seagrass Systems, Zachary Howerton
Phosphorus Cycling In Tropical Carbonate Sediment-Seagrass Systems, Zachary Howerton
OES Theses and Dissertations
This thesis presents two studies focusing on phosphorus cycling in calcium carbonate sediments inhabited by seagrasses. Phosphorus is a major limiting nutrient for primary productivity in these sediments as well as in the overlying waters. In large part this is due to removal of phosphate from solution by adsorption and precipitation reactions.
In chapter II, the relationship between the size of the sedimentary phosphorus pool and the abundance of seagrass on the Great Bahama Bank, as well as the relationship between phosphorus content and grain size in the sediments, were examined to better understand the biogeochemistry of carbonate sediments and …
Stratigraphic Framework, Discontinuity Surfaces, And Regional Significance Of Campanian Slope To Ramp Carbonates From Central Dalmatia, Croatia, M. Brlek, T. Korbar, B. Cvetko Tešović, B. Glumac, L. Fuček
Stratigraphic Framework, Discontinuity Surfaces, And Regional Significance Of Campanian Slope To Ramp Carbonates From Central Dalmatia, Croatia, M. Brlek, T. Korbar, B. Cvetko Tešović, B. Glumac, L. Fuček
Geosciences: Faculty Publications
The sedimentology, microfacies, and stratigraphic age (from planktonic and benthic foraminifera and strontium-isotope stratigraphy) of a 300-m-thick Upper Cretaceous carbonate succession from the Island of Čiovo (central Dalmatia, Croatia) were analyzed in order to determine the lithostratigraphic, depositional, and chronostratigraphic framework. The Cretaceous strata were deposited in the southern part of the long-lasting (Late Triassic to Paleogene) Adriatic-Dinaridic Carbonate Platform (ADCP), one of a few late Mesozoic, intra-Tethyan, peri-Adriatic (sub)tropical archipelagos. The succession is separated by a firmground formational boundary into two lithostratigraphic units: the underlying Middle to Upper Campanian Dol Formation consisting of slope pelagic limestone with intercalated turbidites …
Hydrogeologic Variations Across A Barrier Island That Influence Inter-Dune Wetlands False Cape State Park, Virginia, Matthew Collier Richardson
Hydrogeologic Variations Across A Barrier Island That Influence Inter-Dune Wetlands False Cape State Park, Virginia, Matthew Collier Richardson
OES Theses and Dissertations
False Cape State Park in southeastern Virginia Beach, Virginia contains a transgressive barrier island complex. Inter-dune swales located on the eastern coast of the barrier island contain soils that experience hydric conditions. However, these swales lack the prolonged presence of hydric soil indicators that are necessary for a site to be officially recognized as a jurisdictional wetland. The appearance and subsequent disappearance of redoximorphic wetland soil features in the young, sandy soils of the inter-dune swales here may stem from changes in the patterns of groundwater recharge and discharge across the island. These soils are being monitored by the Mid …
Molecular Characteristics Of The Water Soluable Organic Matter In Size Resolved Aerosols Collected Over The North Atlantic Ocean, Sarah Catherine Gurganus
Molecular Characteristics Of The Water Soluable Organic Matter In Size Resolved Aerosols Collected Over The North Atlantic Ocean, Sarah Catherine Gurganus
Chemistry & Biochemistry Theses & Dissertations
Aerosol particulate matter is acknowledged to have effects on health and the environment and further investigation into the molecular characteristics of aerosols is necessary in order to fully understand the potential links between the molecular characteristics and the impacts that these particles have on health and the environment. Aerosols are often discussed with reference to their size because particles of different sizes can often be associated with different primary sources. This study presents a molecular-level chemical characterization of the water soluble organic matter fraction of 17 aerosol impactor samples representing 3 air mass influences (North American, North African, and marine) …
Jurassic Dinosaurs And Insects: The Paleoecological Role Of Termites As Carcass Feeders, Anne Dangerfield, Dr. Brooks Britt
Jurassic Dinosaurs And Insects: The Paleoecological Role Of Termites As Carcass Feeders, Anne Dangerfield, Dr. Brooks Britt
Journal of Undergraduate Research
My original project focused on the comparison of postcranial bones of two species of Allosaurus with the goal of differentiating the species based on limb robustness. A detailed study of 78 bones showed that there were at least 13 individuals of Allosaurus in the Dry Mesa quarry that belong to Allosaurus jimmadseni. Measurements of the A. jimmadseni specimens were compared with those of A. fragilis from two other institutions. There were no significant differences except for the robustness of the femur bone, which is less robust in A. jimmadseni than A. fragilis. My conclusion is that although the skulls of …
A Preliminary Assessment Of Speleothem Sampling Methods For Paleoclimate Research, Sarah Truebe
A Preliminary Assessment Of Speleothem Sampling Methods For Paleoclimate Research, Sarah Truebe
National Cave and Karst Management Symposium 2013
Speleothems are incomparable archives of paleoclimate information. Most methods to extract past climate information from speleothems are necessarily destructive; sampling must occur along the growth axis. Development of sustainable methods for sampling these nonrenewable resources, whereby the needs of science and cave conservation are balanced, ought to be a priority of the paleoclimate community. Ergo, I am studying currently practiced methods in the field of speleothem paleoclimatology. Part 1 of this two-part study entails surveying active speleothem paleoclimatology labs nationally and internationally. The results of this portion of the survey will be converted to an anonymous list of current methods …
U.S. Drought Monitor, September 24, 2013, Brad Rippey
U.S. Drought Monitor, September 24, 2013, Brad Rippey
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for September 24, 2013 (9/24/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.
Incorporating Satellite Derived Cloud Climatologies To Improve High Resolution Interpolation Of Daily Precipitation., Adam M. Wilson, Benoit Parmentier, Brian Mcgill, Rob Guralnick, Walter Jetz
Incorporating Satellite Derived Cloud Climatologies To Improve High Resolution Interpolation Of Daily Precipitation., Adam M. Wilson, Benoit Parmentier, Brian Mcgill, Rob Guralnick, Walter Jetz
Yale Day of Data
Conservation of biodiversity demands comprehension of evolutionary and ecological patterns and processes that occur over vast spatial and temporal scales. A central goal of ecology is to understand the factors that control the spatial distribution of species and this has become even more important in the face of climate change. However, at global scales there can be enormous uncertainty in environmental data used to model species distributions. Even ‘simple’ metrics such as mean annual precipitation are difficult to estimate in areas with few weather stations and available data sets do not quantify uncertainty in these surfaces. We are developing a …
Unusual Polygenetic Void And Cave Development In Dolomitized Miocene Chalks On Barbados, West Indies, Jonathan B. Sumrall, John E. Mylroie, Hans G. Machel
Unusual Polygenetic Void And Cave Development In Dolomitized Miocene Chalks On Barbados, West Indies, Jonathan B. Sumrall, John E. Mylroie, Hans G. Machel
International Journal of Speleology
Barbados provides an unusual case of polygenetic cave development within dolomitized chalks and marls of the Miocene Oceanics Group. These diagenetic processes are driven by a succession and interplay of tectonic uplift, fracturing, hypogene fluid injection, overprinting by mixing zone diagenesis, and mechanical and biological erosion in the current littoral zone. The significance of the voids and caves within the chalks on Barbados are: 1) these appear to be the first dissolution caves documented in dolomitized chalk, and 2) these features show a polygenetic origin documenting the diagenetic changes in lithology that allowed the development and preservation of these cave …
U.S. Drought Monitor, September 17, 2013, David Miskus
U.S. Drought Monitor, September 17, 2013, David Miskus
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for September 17, 2013 (9/17/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.
Sigma Gamma Epsilon Chapter Service Award, James Walters
Sigma Gamma Epsilon Chapter Service Award, James Walters
The Compass: Earth Science Journal of Sigma Gamma Epsilon
The Chapter Service Award for Sigma Gamma Epsilon was developed, voted on, and approved by the student delegates at the 42nd Biennial Convention in Charlotte, NC, November 3, 2012. The Chapter Service Award is based upon a non-profit/non-chapter fund raising activity that benefits the department, institution, or community. This report provides information on qualifications for eligibility and profiles the two award winning chapters for 2012-2013, Epsilon Eta Chapter at Radford University and Epsilon Theta Chapter at Northwest Missouri State University.
2012 Sigma Gamma Epsilon Austin A. Sartin Best Poster Award, Melissa Gundersen
2012 Sigma Gamma Epsilon Austin A. Sartin Best Poster Award, Melissa Gundersen
The Compass: Earth Science Journal of Sigma Gamma Epsilon
Sigma Gamma Epsilon President Erika Elswick with Melissa Gundersen and Dr.Frederick Vollmer from SUNY New Paltz, the 2012 Austin A. Sartin Best Poster Award winners.
Phanerozoic Surface History Of The Slavecraton, Alexis K. Ault, Rebecca M. Flowers, Samuel A. Bowring
Phanerozoic Surface History Of The Slavecraton, Alexis K. Ault, Rebecca M. Flowers, Samuel A. Bowring
Geosciences Faculty Publications
New apatite (U-Th)/He (AHe) thermochronometry data and key geologic constraints from Slave craton kimberlites are used to develop a model for the Phanerozoic burial, unroofing, and hypsometric history of the northwestern Canadian shield. AHe dates range from 210 ± 13 to 382 ± 79 Ma, are older in the eastern Slave craton and decrease westward, and resolve the spatial extent, thickness, and history of now-denuded sedimentary units. Results indicate Paleozoic heating to temperatures ≥85–90°C, suggesting regional burial beneath ≥2.8 km of strata while the region was at sea level, followed by the westward migration of unroofing across the craton. This …
42nd Biennial Convention Of The Society Of Sigma Gamma Epsilon, Paula Even
42nd Biennial Convention Of The Society Of Sigma Gamma Epsilon, Paula Even
The Compass: Earth Science Journal of Sigma Gamma Epsilon
Sigma Gamma Epsilon, a national honor society for the Earth Sciences, held its 42nd Biennial Convention in conjunction with the annual meeting of the Geological Society of America. The Sigma Gamma Epsilon convention was held at the Westin Hotel in Charlotte, N.C. on November 3, 2012. This report provides a summary of the deliberations and actions of the participants at the convention.
Sigma Gamma Epsilon Quality Chapter Awards, James C. Walters
Sigma Gamma Epsilon Quality Chapter Awards, James C. Walters
The Compass: Earth Science Journal of Sigma Gamma Epsilon
The Quality Chapter Award for Sigma Gamma Epsilon was established to recognize chapters for achieving excellence by providing a quality program to its members. Qualifying criteria for the award are provided, and chapters receiving this award for the 2012-2013 academic year are profiled.
2012 Sigma Gamma Epsilon National Council Best Poster Award, Aaron D. Hiday
2012 Sigma Gamma Epsilon National Council Best Poster Award, Aaron D. Hiday
The Compass: Earth Science Journal of Sigma Gamma Epsilon
Sigma Gamma Epsilon President Erika Elswick with Aaron Hiday from Albion College, the National Council Best Poster Award winner.
New Fossil Crinoids From The Early Mississippian (Kinderhookian) Wassonville Formation Of Southeast Iowa, Forest J. Gahn, Dr. Scott Ritter
New Fossil Crinoids From The Early Mississippian (Kinderhookian) Wassonville Formation Of Southeast Iowa, Forest J. Gahn, Dr. Scott Ritter
Journal of Undergraduate Research
The purpose of this paper is to document a newly discovered assemblage of Early Mississippian (Kinderhookian) fossil crinoids from southeast Iowa. I will provide an introduction and background of the project, followed by the results of the research. Cited references are included at the end of the report.
Paleoseismology Of The Southern Panamint Valley Fault: Implications For Regional Earthquake Occurrence And Seismic Hazard In Southern California, Lee J. Mcauliffe, James F. Dolan, Eric Kirby, Chris Rollins, Ben Haravitch, Steve Alm, Tammy M. Rittenour
Paleoseismology Of The Southern Panamint Valley Fault: Implications For Regional Earthquake Occurrence And Seismic Hazard In Southern California, Lee J. Mcauliffe, James F. Dolan, Eric Kirby, Chris Rollins, Ben Haravitch, Steve Alm, Tammy M. Rittenour
Geosciences Faculty Publications
[1] Paleoseismologic data from the southern Panamint Valley fault (PVF) reveal evidence of at least four surface ruptures during late Holocene time (0.33–0.48 ka, 0.9–3.0 ka, 3.3–3.6 ka, and >4.1 ka). These paleo‐earthquake ages indicate that the southern PVF has ruptured at least once and possibly twice during the ongoing (≤1.5 ka) seismic cluster in the Mojave section of the eastern California shear zone (ECSZ). The most recent event (MRE) on the PVF is also similar in age to the 1872 Owens Valley earthquake and the geomorphically youthful MRE on the Death Valley fault. The timing of the three oldest …
Wmu Research Facility Assists In Rediscovery Of Rare Mineral Deposit, Cheryl Roland
Wmu Research Facility Assists In Rediscovery Of Rare Mineral Deposit, Cheryl Roland
MGRRE News
WMU News article about the rediscovery of a long-forgotten mineral deposit, potash, which is located under two West Michigan counties.
U.S. Drought Monitor, September 10, 2013, Anthony Artusa
U.S. Drought Monitor, September 10, 2013, Anthony Artusa
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for September 10, 2013 (9/10/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.
Study Of An Archeological Site Near Mount Vesuvius Using Ground-Penetrating Radar Pollena Trocchia, Italy, Robert Weight, Dr. John Mcbride
Study Of An Archeological Site Near Mount Vesuvius Using Ground-Penetrating Radar Pollena Trocchia, Italy, Robert Weight, Dr. John Mcbride
Journal of Undergraduate Research
A major archeological excavation is ongoing for a Roman site near Mt. Vesuvius in the modern town of Pollena Trocchia, Italy. The excavation is being pursued as collaboration between BYU and the University of Naples. The excavation is being done in a present day urban setting therefore the excavators must be strategic in their methods and guided by whatever tools possible to avoid public disruption. A ground penetrating radar or GPR survey was completed which provided images of buried structures, collapsed buildings, and horizontal volcanic ash beds covering the site. These geophysical methods have assisted in a more timely and …
Integrated Three-Dimensional Geophysical Analysis Of The Wasatch Fault Zone Near Rock Canyon, Provo, Utah, Leo T. Brown, Dr. Alvin K. Benson
Integrated Three-Dimensional Geophysical Analysis Of The Wasatch Fault Zone Near Rock Canyon, Provo, Utah, Leo T. Brown, Dr. Alvin K. Benson
Journal of Undergraduate Research
The Wasatch fault zone extends from southern Idaho into central Utah, and approximately ninety percent of Utah’s population live in or near this fault zone. Surface rupture and ground shaking associated with earthquake events represent the biggest geologic hazards to people and structures within this fault zone. Movement and rupture will most likely occur along preexisting zones of weakness or faults. In order to mitigate damage to buildings and loss of lives, the locations of individual faults within the fault zone should be determined as accurately as possible.
Origin And Provenance Of Spherules And Magnetic Grains At The Younger Dryas Boundary, Yingzhe Wu, Mukul Sharma, Malcom A. Lecompte, Mark N. Demitroff, Joshua D. Landis
Origin And Provenance Of Spherules And Magnetic Grains At The Younger Dryas Boundary, Yingzhe Wu, Mukul Sharma, Malcom A. Lecompte, Mark N. Demitroff, Joshua D. Landis
Dartmouth Scholarship
One or more bolide impacts are hypothesized to have triggered the Younger Dryas cooling at ∼12.9 ka. In support of this hypothesis, varying peak abundances of magnetic grains with iridium and magnetic microspherules have been reported at the Younger Dryas boundary (YDB). We show that bulk sediment and/or magnetic grains/microspherules collected from the YDB sites in Arizona, Michigan, New Mexico, New Jersey, and Ohio have (187)Os/(188)Os ratios ≥1.0, similar to average upper continental crust (= 1.3), indicating a terrestrial origin of osmium (Os) in these samples. In contrast, bulk sediments from YDB sites in Belgium and Pennsylvania exhibit (187)Os/(188)Os ratios <<1.0 and at face value suggest mixing with extraterrestrial Os with (187)Os/(188)Os of ∼0.13. However, the Os concentration in bulk sample and magnetic grains from Belgium is 2.8 pg/g and 15 pg/g, respectively, much lower than that in average upper continental crust (=31 pg/g), indicating no meteoritic contribution. The YDB site in Pennsylvania is remarkable in yielding 2- to 5-mm diameter spherules containing minerals such as suessite (Fe-Ni silicide) that form at temperatures in excess of 2000 °C. Gross texture, mineralogy, and age of the spherules appear consistent with their formation as ejecta from an impact 12.9 ka ago. The (187)Os/(188)Os ratios of the spherules and their leachates are often low, but Os in these objects is likely terrestrially derived. The rare earth element patterns and Sr and Nd isotopes of the spherules indicate that their source lies in 1.5-Ga Quebecia terrain in the Grenville Province of northeastern North America.
U.S. Drought Monitor, September 3, 2013, David Miskus
U.S. Drought Monitor, September 3, 2013, David Miskus
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for September 3, 2013 (9/3/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.
The Earthquake History Of Eastern Indonesia, Jonathan Major, Jamie Robinson, Dr. Ron Harris
The Earthquake History Of Eastern Indonesia, Jonathan Major, Jamie Robinson, Dr. Ron Harris
Journal of Undergraduate Research
Indonesia is the fourth largest country in the world by population and encompasses thousands of islands. The tropical climate, fertile soil, and vast natural resources continue to fuel rapid population and economic growth. Much of the natural abundance of Indonesia can be attributed to its active and complex geology. Hundreds of volcanoes build, shape, and destroy islands while powerful earthquakes rock the land and sometimes generate devastating tsunamis. The Great Sumatra-Andaman earthquake and tsunami of 2004 is a sobering reminder of the region’s destructive potential. This event was not a surprise to a handful of researchers like Dr. Ron Harris …
Scavenging, Cycling And Removal Fluxes Of 210Po And 210Pb At The Bermuda Time-Series Study Site, G. H. Hong, M. Baskaran, T. M. Church, M. Conte
Scavenging, Cycling And Removal Fluxes Of 210Po And 210Pb At The Bermuda Time-Series Study Site, G. H. Hong, M. Baskaran, T. M. Church, M. Conte
Environmental Science and Geology Faculty Research Publications
Quantifying relative affinities of Po and Pb in different populations of marine particulate matter is of great importance in utilizing 210Po as a tracer for carbon cycling. We collected and analyzed water samples for the concentrations of dissolved and total 210Po and 210Pb from the upper 600 m of the water column at Bermuda Time-series Study site (September 1999 to September 2000) to investigate their seasonality of concentrations and their ac-tivity ratio (210Po/210Pb activity ratio, AR). Sinking particles collected in sediment traps at depths of 500 m, 1500 m, and 3200 m from …
Ua66 Ogden College Of Science & Engineering Newsletter, Cheryl Stevens, Dean
Ua66 Ogden College Of Science & Engineering Newsletter, Cheryl Stevens, Dean
Ogden College of Science & Engineering Publications
No abstract provided.
Report Card On Sustainable Natural Resource Use In Agriculture, Robert Summers, David Weaver
Report Card On Sustainable Natural Resource Use In Agriculture, Robert Summers, David Weaver
All other publications
Condition and trend Nutrients, such as phosphorus (P), are essential for profitable agriculture in the south-west of WA; however, excess P – more than is required for optimal production – is stored in many agricultural soils. On average, pasture soils and arable soils contain 1.3 times and 1.6 times respectively, as much P as is required for optimal production. Production in P-enriched soils is more likely to be constrained by soil acidity (50–60% of pasture and arable soils), potassium (K) (50% of pasture soils and less than 10% of arable soils), and sulphur (S) (30% of pasture soils). Management implications …
Holocene Fire Occurrence And Alluvial Responses At The Leading Edge Of Pinyon–Juniper Migration In The Northern Great Basin, Usa, Kerrie N. Weppner, Jennifer L. Pierce, Julio L. Betancourt
Holocene Fire Occurrence And Alluvial Responses At The Leading Edge Of Pinyon–Juniper Migration In The Northern Great Basin, Usa, Kerrie N. Weppner, Jennifer L. Pierce, Julio L. Betancourt
Geosciences Faculty Publications and Presentations
Fire and vegetation records at the City of Rocks National Reserve (CIRO), south-central Idaho, display the interaction of changing climate, fire and vegetation along the migrating front of single-leaf pinyon (Pinus monophylla) and Utah juniper (Juniperus osteosperma). Radiocarbon dating of alluvial charcoal reconstructed local fire occurrence and geomorphic response, and fossil woodrat (Neotoma) middens revealed pinyon and juniper arrivals. Fire peaks occurred ~10,700–9500, 7200–6700, 2400–2000, 850–700, and 550–400 cal yr BP, whereas ~9500–7200, 6700–4700 and ~1500–1000 cal yr BP are fire-free. Wetter climates and denser vegetation fueled episodic fires and debris flows during the …
Accommodation Space Controls On The Latest Pleistocene And Holocene (16–0 Ka) Sediment Size And Bypassing In The Lower Columbia River Valley: A Large Fluvial–Tidal System In Oregon And Washington, Usa, Curt D. Peterson
Geology Faculty Publications and Presentations
In this study, we establish the roles that increasing basin accommodation space have on sediment size and bypassing in the transgressive fill (16–0 ka) in the submerged Lower Columbia River Valley (LCRV). The antecedent forearc valley (225 km in length, 4–8 km in width, and 60–115 m in axial valley depth) is characterized by high sediment supply rates (10–15 million t y-1) but no delta at its mouth to the Pacific Ocean. Core sample sediment textures (N ¼ 1600) are analyzed from 3000 m of borehole sections in 58 representative boreholes to characterize the ancestral valley fill: 57% sand, 17% …