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Articles 24241 - 24270 of 29959
Full-Text Articles in Geology
Evolution Of High Tooth Replacement Rates In Sauropod Dinosaurs, Michael D. D'Emic, John A. Whitlock, Kathlyn M. Smith, Daniel C. Fisher, Jeffrey A. Wilson
Evolution Of High Tooth Replacement Rates In Sauropod Dinosaurs, Michael D. D'Emic, John A. Whitlock, Kathlyn M. Smith, Daniel C. Fisher, Jeffrey A. Wilson
Earth, Environment & Sustainability: Faculty Publications
Background: Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates.
Methodology/Principal Findings: We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined …
Olivine Ca Content Measured By Icp-Oes To Estimate P-T, Bradley Benavides
Olivine Ca Content Measured By Icp-Oes To Estimate P-T, Bradley Benavides
Open Access Theses & Dissertations
Ca is a trace element in olivine and its concentration is pressure and temperature dependent, providing a rare opportunity to estimate pressure conditions at which mantle-derived rocks (xenoliths) last equilibrated. This P-T dependence has previously been calibrated for mantle xenoliths, and we applied this technique to samples from Jasper Seamount (Jasper Seamount), an oceanic intraplate volcano (OIV) off the coast of the Baja California Peninsula of Mexico. Preliminary compositions for xenoliths from this location appear to define a magmatic plumbing system that features magma storage near the bottom of the crust. A more detailed analysis of the samples is required …
Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez
Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez
Open Access Theses & Dissertations
No abstract provided.
In-Situ, Integrated U-Pb, Hf And O Isotopic Study Of Igneous, Metamorphic And Detrital Zircons. Implications To Crustal Evolution And Geodynamics, Munazzam Ali Mahar
In-Situ, Integrated U-Pb, Hf And O Isotopic Study Of Igneous, Metamorphic And Detrital Zircons. Implications To Crustal Evolution And Geodynamics, Munazzam Ali Mahar
Open Access Theses & Dissertations
Zircon data from South Karakoram gneiss dome provide evidence for Proterozoic inherited cores (1.8-1.9 Ga and 2.3-.2.5 Ga) surrounded by migmatitic overgrowth with ages ranging from ~6 to ~20Ma. Oxygen isotopic data of Neogene migmatite and inherited core is similar and indistinguishable ranging from 7.5 to 9.5 /. However, Neogene overgrowth is significantly less evolved than the inherited core in terms of Hf composition. This implies that the Hf composition of the migmatitic zircons is not controlled exclusively by the dissolution of the inherited cores and that contamination by external melts is likely. Isotopic data from the Baltoro plutonic unit …
The Eolian-Sabkha Transition In The Permian Cedar Mesa Sandstone, Se Utah, Alexandra Massad
The Eolian-Sabkha Transition In The Permian Cedar Mesa Sandstone, Se Utah, Alexandra Massad
Open Access Theses & Dissertations
This study focuses on the depositional transition between the Permian Cedar Mesa sand dune sea and the adjoining fluvial, lacustrine, playa and a sabkha facies. This transition provides insights into how climate and environment interacted in this unique setting where up to 300 m of eolian sands transition into evaporites. The evaporites are less common as tongues within the eolianites than previously thought and there were several environments that were observed that haven't been previously described or observed in the Cedar Mesa. The arrangement of the various units within the study area support the climate control on stratigraphy.
The intertonguing …
Geology And Geochemistry Of The Sierra Blanca Rare Earth Complex, Sierra Blanca, Texas, Nicole Kyger
Geology And Geochemistry Of The Sierra Blanca Rare Earth Complex, Sierra Blanca, Texas, Nicole Kyger
Open Access Theses & Dissertations
With an increasing standard of living comes an increase in demand for high tech goods, environmentally friendly (green) and military technologies, and the inherent need to procure the necessary raw materials. Demand for the rare earth elements (REE) is on the rise, and there is no foreseeable decline in the need for accessible deposits. Between 2010 and present, the United States Congress has heard numerous reports on the importance of REE, and in 2012 the Department of Defense(DoD)declared REE a critical resource, with implications for national security. The Sierra Blanca laccoliths, 150 kilometers southeast of El Paso, TX represent a …
Integrated Geological And Geophysical Studies Of The Indio Mountains And Hueco Bolson, West Texas, Pawan Budhathoki
Integrated Geological And Geophysical Studies Of The Indio Mountains And Hueco Bolson, West Texas, Pawan Budhathoki
Open Access Theses & Dissertations
This Dissertation consists of two different projects. The first project describes the results of an outcrop based sequence stratigraphic study of the Albian Cox Sandstone in the Indio Mountains of west Texas. The depositional environment of the Cox Sandstone ranges from shallow marine to the coastal plain deposited in four sequences where sequence 1 and sequence 2 consists of transgressive system tracts (TST) followed by highstand system tracts (HST). The highstand system tract (HST) is missing in sequence 3 and the transgressive systems tract is missing in sequence 4. The Cox changes in thickness from 320 m in the northern …
Seismic Reflection Exploration Of Geothermal Reservoir Atnaval Air Station (Nas) Fallon, Nevada, Alay Ghebremariam Gebregiorgis
Seismic Reflection Exploration Of Geothermal Reservoir Atnaval Air Station (Nas) Fallon, Nevada, Alay Ghebremariam Gebregiorgis
Open Access Theses & Dissertations
The Primary objective of this study is to increase geologic and tectonic understanding of the geothermal resources at the Naval Air Station (NAS) Fallon, Nevada. The seismic reflection method is employed to study faults, fractures and other tectonic structures in the subsurface in order to identify geothermal drill targets. The efficiency of geothermal systems is strongly dependent on water circulation. Discrete faults may be permeable and provide pathways for water flow depending on the fracture density. It is therefore desirable to detect and map faults and fracture zones and characterize their physical properties when evaluating a geothermal prospect.
The seismic …
Application Of Various Remote Sensing And Aerial Photography Data Sets To Resolve Surface Structure In Areas Of Poor Exposure: Examples From Kamchatka Peninsula, Russia And Katalla Area, Alaska Usa, Sarah Natalie Heinlein
Application Of Various Remote Sensing And Aerial Photography Data Sets To Resolve Surface Structure In Areas Of Poor Exposure: Examples From Kamchatka Peninsula, Russia And Katalla Area, Alaska Usa, Sarah Natalie Heinlein
Open Access Theses & Dissertations
For many years now remote sensing data sets and application techniques of these various data have been routinely used in geological studies. Some of these studies are as basic as using Google Earth applications for general reconnaissance to more sophisticated methods for energy exploration or development of active tectonic models for a region. This dissertation presents data from two study areas within the northern pacific region utilizing a number of remote sensing and aerial photography data: 1) Kamchatka Peninsula, Russia, and 2) Katalla area of southern Alaska, USA. The Kamchatka Peninsula, Russia study evaluates surface geomorphology which includes the morphology …
Depositional Setting And Sequence Stratigraphic Analysis Of The Lower Permian Lower Hueco Formation On The Western Margin Of The Orogrande Basin, South Central New Mexico, Jonathon Eric Stautberg
Depositional Setting And Sequence Stratigraphic Analysis Of The Lower Permian Lower Hueco Formation On The Western Margin Of The Orogrande Basin, South Central New Mexico, Jonathon Eric Stautberg
Open Access Theses & Dissertations
On the western margin of the Orogrande Basin in south-central New Mexico, eight outcrop datasets, in the form of measured stratigraphic sections from the lower interval of the Lower Permian Lower Hueco Formation were analyzed in regard to depositional facies distribution and sequence stratigraphy. Based on petrographic analysis of 247 samples and associated field relationships, 11 depositional facies are recognized: 1) quartz sandstone, 2) quartz siltstone and shale, 3) fenestral dolomudstone, 4) microbial intraclast packstone, 5) dolomudstone, 6) green-algal packstone to grainstone, 7) ostracode foram wackestone, 8) oolitic packstone, 9) fossiliferous packstone and grainstone, 10) fusulinid packstone and grainstone, 11) …
Biorecognition Ability Of Polysaccharides As Piezo Quartz Biosensors, En Kalmykova, Ca Mgina
Biorecognition Ability Of Polysaccharides As Piezo Quartz Biosensors, En Kalmykova, Ca Mgina
Tanzania Journal of Science
Piezoquartz biosensors (PQB) which are analytical devices for recognition of biochemical interactions have recently attracted increasing interest from different researchers such as analysts, immune-chemists, medical doctors, environmentalists, etc. This is due to the advantages of PQB for having high detection sensitivity (at ng and mg level depending on the mass of sorbates or micro-organisms) and the ability to monitor biochemical reactions in turbid or highly coloured liquids (including in biological fluids) in real time. The use of additional markers and preliminary sample preparation are not required in this biorecognition process. This paper reports on the principle of the PQB and …
Theoretical Study Of Physiochemical Properties Of Insulin-Like Growth Factor 1, A Ilkhani
Theoretical Study Of Physiochemical Properties Of Insulin-Like Growth Factor 1, A Ilkhani
Tanzania Journal of Science
The computational approach to studying structural changes in a wide range of physical and biological problems, the empirical force fields, have great difficulty in simulating folding of Insulin-like Growth Factor 1 (IGF-1). In an effort to understand the conformational preferences that may be attributed to stereoelectronic effects, a number of computational studies were carried out. Monte Carlo, Molecular Dynamics and Langevin simulation methods by MM+, AMBER and OPLS force fields of calculations have been performed on IGF-1 as growth factors. The parameters of a minimized structure of IGF-1, calculated potential energy for important dihedral angles and the effect of temperature …
Salt Lakes Of The African Rift System: A Valuable Research Opportunity For Insight Into Nature’S Concenrtated Multi-Electrolyte Science, Jyn Philip, Dms Mosha
Salt Lakes Of The African Rift System: A Valuable Research Opportunity For Insight Into Nature’S Concenrtated Multi-Electrolyte Science, Jyn Philip, Dms Mosha
Tanzania Journal of Science
The Tanzanian rift system salt lakes present significant cultural, ecological, recreational and economical values. Beyond the wealth of minerals, resources of these rift salt lakes include unique wildlife, for instance Lesser Flamingo (Phoenicopterus minor) and Cichlids (Alcolapia spp), which adapted chemically aggressive environments like that of Lake Natron. The general hydrochemical equilibria of these salt lakes is governed by Na+ > K+ >> Ca2+ ~ Mg2+ : (CO32- + HCO3-) > Cl- > SO42-~ F- ionic concentration pattern. Salt accumulation mechanism in these endorheic lakes is considered to base on thermo-mechanical disintegrative stress of the geochemistry sourcing. The rains chemically interact with rift terrains, …
Geochemical Evidence For Vertical Migration Of Deep Formation Fluids Through The Baton Rouge -Denham Springs Fault System, Lesley C. Prochaska
Geochemical Evidence For Vertical Migration Of Deep Formation Fluids Through The Baton Rouge -Denham Springs Fault System, Lesley C. Prochaska
LSU New Orleans Theses and Dissertations
Accumulations of brackish groundwater exist across south Louisiana within the shallow, south-dipping Pleistocene to Upper Miocene Baton Rouge Aquifer System (BRAS). This research investigates the source of brackish groundwater through geochemical analysis of representative groundwater samples by comparing the following geochemical ratios along with other trace elements. Low Bromide (Br)/Chloride (Cl) and Potassium (K) /Cl ratios, high Sodium (Na) /Cl ratios, trace Magnesium (Mg) concentrations, and low Strontium (Sr) 87/Sr86 in brackish waters from the BRAS are inconsistent with in situ saline water from marine formation fluids of similar age. The ratios are consistent with in situ saline-water …
Geomorphologic Evolution Of A Rapidly Deteriorating Barrier Island System With Multiple Sediment Sources: Eastern Isles Dernieres, Louisiana, 1887 To 2006, Benjamin T. Kirkland
Geomorphologic Evolution Of A Rapidly Deteriorating Barrier Island System With Multiple Sediment Sources: Eastern Isles Dernieres, Louisiana, 1887 To 2006, Benjamin T. Kirkland
LSU New Orleans Theses and Dissertations
Trinity, East, and Wine Islands make up the eastern half of the Isles Dernieres barrier arc in south-central Louisiana. Formed following the abandonment of the Lafourche delta complex, subsidence and storm erosion have led to rapid deterioration of the system. Since 1887, the land area of the islands has decreased seventy-seven percent, and the gulf shoreline has retreated landward more than a kilometer. Wave ravinement on the shoreface of the islands is responsible for the most sediment loss; liberated sediment travels longshore to tidal inlets. The dominant ebb tidal currents then transport the sediment to where it is deposited in …
Characterization Of The Red Bluff Landslide, Greater Cascade Landslide Complex, Columbia River Gorge, Washington, James Robert Randall
Characterization Of The Red Bluff Landslide, Greater Cascade Landslide Complex, Columbia River Gorge, Washington, James Robert Randall
Dissertations and Theses
Located in the Columbia River Gorge, The Red Bluff Landslide (18.8 km2) is one of four large landslides that make up the Cascade Landslide Complex. In its current form, the Red Bluff Landslide is a post-Missoula Flood feature made up of two components: an active upper lobe (8.6 km2) that is translational, creeping to the south at 25 cm/yr and spreading laterally to the east at 6 cm/yr over a semi-fixed portion (10.2 km2) of the Red Bluff Landslide area that has been "smoothed" by Missoula Floods. The upper active lobe is the landslide debris accumulated since Missoula Flood time …
Using Marine Snails To Teach Biogeography And Macroevolution: The Role Of Larvae And Dispersal Ability In The Evolution And Persistence Of Species, Jonathan R. Hendricks
Using Marine Snails To Teach Biogeography And Macroevolution: The Role Of Larvae And Dispersal Ability In The Evolution And Persistence Of Species, Jonathan R. Hendricks
Faculty Publications
While some marine animals are capable of traveling great distances, many have limited mobility as adults and spend the majority of their lifetimes in a small geographical area or may even be cemented to a single place. While it might be expected that species with limited mobility would have small geographic distributions, some nevertheless occur over very large areas. This is the case for some marine snails (gastropods). A key factor that impacts the geographic distribution of marine snails is the type of larvae they have during the phase of their life history that follows hatching from an egg. Because …
Chemical Contaminants As Stratigraphic Markers For The Anthropocene, Michael A. Kruge
Chemical Contaminants As Stratigraphic Markers For The Anthropocene, Michael A. Kruge
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Thousands and even millions of years from now, widespread anthropogenic contaminants in sediments would likely persist, incorporated into the geological record. They would inadvertently preserve evidence of our present era (informally designated as the Anthropocene Epoch) characterized by large human populations engaged in intensive industrial and agricultural activities.
Hypothetical geologists in the distant future would likely find unusually high concentrations of a wide variety of contaminants at stratigraphic levels corresponding to our present time, analogous to the iridium anomaly marking the bolide impact event at the close of the Cretaceous Period. These would include both organic and inorganic substances, such …
Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski
Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski
All Theses
Some fractured rock formations hold important resources, such as water, hydrocarbons or heat, whereas others are good candidates for waste disposal. Hydromechanical well tests have been developed to improve characterization of formation properties and parameter distributions by measuring displacement along with pressure while stressing a well. The displacement that occurs during a well test depends on the geometry of fractures or other sources of permeability, as well as the distribution of compliance or elastic modulus. Current methods of hydromechanical well testing, measures axial displacements along a wellbore, which may cause ambiguity in interpretations when 3-D components of deformation are present. …
Stratigraphic Variations In The Carboniferous Section Across The Arkansas-Oklahoma State Line Arch, Tyler Dean Engelhardt
Stratigraphic Variations In The Carboniferous Section Across The Arkansas-Oklahoma State Line Arch, Tyler Dean Engelhardt
Graduate Theses and Dissertations
The State Line Arch is represented by a structural high that trends through the study area in a loose alignment with the Arkansas-Oklahoma state line. Evidence of the arch extending further to the north includes a structural high and stratigraphic variation at an outcrop on Highway 59 near Evansville Mountain in Crawford County, Arkansas. The exact timing of the formation of the arch remains undetermined, but upper Devonian thinning at the top of the arch indicates the structure is pre-Mississippian. The reason for the development of the arch is poorly understood, but evidence linking Mississippian-aged Waulsortian mounds to Precambrian Spavinaw …
Determining Temperatures Of Deformation In Mylonites From The Scandinavian Caledonides, With Implications For The Thermal And Kinematic Evolution Of Orogens, Andrea Marilina Wolfowicz
Determining Temperatures Of Deformation In Mylonites From The Scandinavian Caledonides, With Implications For The Thermal And Kinematic Evolution Of Orogens, Andrea Marilina Wolfowicz
Boise State University Theses and Dissertations
The Titanium-in-quartz (TitaniQ) thermobarometer was evaluated in ductilely sheared rocks (mylonites) from the Scandinavian Caledonides in comparison with several other thermometric methods, including: (1) TitaniQ thermometry in cross-cutting quartz veins, (2) garnet-biotite Fe-Mg exchange thermometry, (3) metamorphic phase equilibria, and (4) quartz microstructures as calibrated experimentally and empirically. In all instances, quartz vein temperatures mimic TitaniQ temperatures of the host rocks. Similarly, TitaniQ temperatures of dynamically recrystallized quartz, ranging from ~210°C at the thrust front to 475°C at the deepest structural levels, reflect the best estimate of the final temperature of deformation. Higher temperatures are also preserved locally and more …
Ore And Gangue Mineral Paragenesis Of The Cortez Hills Carlin-Type Gold Deposit, Nevada: Evidence For Coincident High-Grade Gold Deposition And Collapse Brecciation, Lindsey R. Clark
UNLV Theses, Dissertations, Professional Papers, and Capstones
The Cortez Hills Carlin-type gold deposit (CTGD), located on the Battle Mountain-Eureka trend of Northern NV, is hosted in a conical shaped polylithic breccia whose central axis strikes parallel to the imbricate Voodoo fault system. Gold grades at the center of the Cortez Hills Breccia Zone (CHBZ) are locally in excess of an ounce per ton. Gold mineralization within the refractory ore at Cortez Hills shares many characteristics with other well studied CTGDs. However, new observations during this study have recognized 1) fragmented realgar that are rimmed by gold-bearing iron-sulfide minerals in four samples, 2) a Hg- and Tl-rich late-ore …
Petrogenesis Of The East Fork Member Rhyolites, Valles Caldera, New Mexico, Usa, Carla Eichler
Petrogenesis Of The East Fork Member Rhyolites, Valles Caldera, New Mexico, Usa, Carla Eichler
UNLV Theses, Dissertations, Professional Papers, and Capstones
The most recent volcanism in the Valles caldera is represented by the El Cajete Pyroclastic Beds (ECPB), Battleship Rock Ignimbrite (BRI), and Banco Bonito Flow (BBF) as well as the VC-1 rhyolite, which are collectively known as the East Fork Member (EFM) of the Valles Rhyolite. The EFM was erupted at approximately 55 ka and 40 ka after an approximate 460 ka lull in volcanism. Previous studies suggested a mafic intrusion at depth triggered the eruptions. This thesis represents the first detailed study of the EFM.
Crystal assemblages consist of plagioclase, biotite, clinopyroxene, orthopyroxene, amphibole, sanidine, quartz, and oxides. Electron …
Volcanic Evolution Of The Southern Quinn Canyon Range: Implications For Regional Correlation Of Volcanic Units, Christina Emery
Volcanic Evolution Of The Southern Quinn Canyon Range: Implications For Regional Correlation Of Volcanic Units, Christina Emery
UNLV Theses, Dissertations, Professional Papers, and Capstones
The southern Quinn Canyon Range lies in an area of the Great Basin subjected to large-volume Oligocene-Miocene silicic volcanism and smaller volume basaltic volcanism during the Pliocene. Three major ash-flow tuff units were correlated in the southern Quinn Canyon Range (the Pahranagat Tuff, Clifford Spring Tuff, and the Cow Canyon Tuff) with regional units by utilizing U/Pb and 40 Ar/ 39Ar geochronology, geochemical correlation, and field mapping. Isotopic analysis suggests that basalt in the southern Quinn Canyon Range is part of the Death Valley-Pancake Range Basalt Zone and is similar to Reveille Range Episode 1 and 2 basalts. Further comparison …
An Estimate Of Groundwater Recharge In The Nabogo River Basin, Ghana Using Water Table Fluctuation Method And Chloride Mass Balance, Melanie Lynn Krautstrunk
An Estimate Of Groundwater Recharge In The Nabogo River Basin, Ghana Using Water Table Fluctuation Method And Chloride Mass Balance, Melanie Lynn Krautstrunk
UNLV Theses, Dissertations, Professional Papers, and Capstones
The Cambrian-Precambrian fractured sandstone aquifer in the Nabogo River Basin in the Sahelian Northern Region in Ghana is one of the most important sources for fresh water supply for the local rural communities there. Recent population growth and commercial agricultural interests in this region could have an impact on this critical water resource. Groundwater recharge estimates are determined in this study using the Water Table Fluctuation Method and Chloride Mass Balance and can be applied to future sustainability studies of the region's water resources. Recharge estimates of the Water Table Fluctuation Method are in a range of 10-143 mm/yr or …
2000 Year Moisture Source Record From A Central Nevada Speleothem, Paul Pribyl
2000 Year Moisture Source Record From A Central Nevada Speleothem, Paul Pribyl
UNLV Theses, Dissertations, Professional Papers, and Capstones
The goal of this study was to determine the moisture source of winter precipitation in the central Great Basin for the past 2000 years, and to elucidate the role of Pacific Ocean and North American climate variability modes in driving observed droughts of the region around the Medieval Climatic Anomaly (MCA, ~900-1300 CE). Here a high resolution (~2-4 year) precisely dated moisture source reconstruction is presented from the δ18O values of speleothem LC-1 collected from Leviathan Cave in central Nevada, which reveals significant δ18O variability. I attribute the δ18O variability to changes in winter-season moisture circulation over the past 2000 …
Integrated Approach For Hydrogeologic Investigations In Africa: Inferences From Space-Borne And Land-Based Gravity, Aeromagnetic, Gis, And Remote Sensing Data, Mohamed El Sayed Ahmed Ahmed
Integrated Approach For Hydrogeologic Investigations In Africa: Inferences From Space-Borne And Land-Based Gravity, Aeromagnetic, Gis, And Remote Sensing Data, Mohamed El Sayed Ahmed Ahmed
Dissertations
An integrated (space-borne and land-based gravity, aeromagnetic, GIS, and remote sensing) approach was developed, tested, and applied to investigate the following on regional scales (Africa) or local scales (El Qaa Plain, Sinai): (1) assess the capability of GRACE data (04/2002 to 08/2011) for monitoring elements of hydrologic systems on the sub-basin level (Task 1); (2) address the nature and the controlling factors (e.g., climatic and/or human pressure-related) affecting the inter-annual GRACE-derived Terrestrial Water Storage (TWS) trends over a large suite of hydrologic systems and domains in (Africa) (Task 2); and (3) identify the structural, geologic and hydrologic settings as well …
Detrital Carbonates In A Sequence Stratigraphic Framework: An Example From The Furongian Slope Environment In The Hot Creek Range Of Central Nevada, Leon Taufani
UNLV Theses, Dissertations, Professional Papers, and Capstones
An integrated sedimentological study of detrital carbonates of the late Cambrian (Furongian) Hales Limestone in central Nevada was conducted in order to model facies distribution and controlling mechanisms of carbonate gravity-flow deposits. Seven closely-spaced sections and numerous traceable short sections were measured to investigate temporal and spatial changes of detrital carbonates within a high-resolution stratigraphic framework supported by biostratigraphic and carbon isotope chemostratigraphic constraints and by key physical surfaces. Polished slabs and thin section petrographic analysis were used to identify micro- and macro-scale textures and diagenesis.
Ten lithofacies are identified from the Hales Limestone. Lateral tracing of these facies reveals …
Autumn Migration Of Mississippi Flyway Mallards As Determined By Satellite Telemetry, David George G. Krementz, Kwasi Asante, Luke W. Naylor
Autumn Migration Of Mississippi Flyway Mallards As Determined By Satellite Telemetry, David George G. Krementz, Kwasi Asante, Luke W. Naylor
United States Geological Survey: Staff Publications
We used satellite telemetry to study autumn migration timing, routes, stopover duration, and final destinations of mallards Anas platyrhynchos captured the previous spring in Arkansas from 2004 to 2007. Of those mallards that still had functioning transmitters on September 15 (n = 55), the average date when autumn migration began was October 23 (SE = 2.62 d; range = September 17–December 7). For those mallards that stopped for .1 d during migration, the average stopover length was 15.4 d (SE = 1.47 d). Ten mallards migrated nonstop to wintering sites. The eastern Dakotas were a heavily utilized stopover area. The …
Stratigraphic Framework For Deposits Of The Saginaw Lobe, Barry And Calhoun Counties, Michigan, Usa, Stephanie K. Ewald
Stratigraphic Framework For Deposits Of The Saginaw Lobe, Barry And Calhoun Counties, Michigan, Usa, Stephanie K. Ewald
Masters Theses
Between 2006 and 2012, twelve rotasonic borings were drilled in Barry and Calhoun Counties, south central Michigan, as part of several Great Lakes Geological Mapping Coalition projects. Natural gamma ray logs were collected at every location and a detailed description and textural analysis was completed for seven of these cores. Five of the seven analyzed cores reached bedrock. Six of the seven borings were drilled north of the Kalamazoo Moraine of the Saginaw Lobe, which was constructed during retreat of the lobe after the Late Glacial Maximum. Five borings, drilled in tunnel valleys, indicate an increase in depth of tunnel …