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Articles 1 - 30 of 2290
Full-Text Articles in Geophysics and Seismology
The Kanarra Fold-Thrust Structure - The Leading Edge Of The Sevier Fold-Thrust Belt, Southwestern Utah: Geology Of The Intermountain West, William J. Chandonia, John P. Hogan
The Kanarra Fold-Thrust Structure - The Leading Edge Of The Sevier Fold-Thrust Belt, Southwestern Utah: Geology Of The Intermountain West, William J. Chandonia, John P. Hogan
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The multiple origins proposed for the Kanarra anticline in southwestern Utah as a drag-fold along the Hurricane fault, a Laramide monocline, a Sevier fault-propagation fold, or a combination of these processes, serve to muddy its tectonic significance. This in part reflects the structural complexity of the exposed eastern half of the fold. The fold evolved from open and up-right to overturned and tight, is cross-cut by multiple faults, and was subsequently dismembered by the Hurricane fault. The western half of the fold is obscured because of burial, along with the hanging wall of the Hurricane fault, beneath Neogene and younger …
Operational Water Forecast Ability Of The Hrrr-Isnobal Combination: An Evaluation To Adapt Into Production Environments, Joachim Meyer, John Horel, Patrick Kormos, Andrew Hedrick, Ernesto Trujillo, S. Mckenzie Skiles
Operational Water Forecast Ability Of The Hrrr-Isnobal Combination: An Evaluation To Adapt Into Production Environments, Joachim Meyer, John Horel, Patrick Kormos, Andrew Hedrick, Ernesto Trujillo, S. Mckenzie Skiles
Geosciences Faculty Publications and Presentations
Operational water-resource forecasters, such as the Colorado Basin River Forecast Center (CBRFC) in the Western United States, currently rely on historical records to calibrate the temperature-index models used for snowmelt runoff predictions. This data dependence is increasingly challenged, with global and regional climatological factors changing the seasonal snowpack dynamics in mountain watersheds. To evaluate and improve the CBRFC modeling options, this work ran the physically based snow energy balance iSnobal model, forced with outputs from the High-Resolution Rapid Refresh (HRRR) numerical weather prediction model across 4 years in a Colorado River Basin forecast region. Compared to in situ, remotely sensed, …
Magnetic Anomaly Data Products Of The Central And Eastern United States, Dhananjay Ravat
Magnetic Anomaly Data Products Of The Central And Eastern United States, Dhananjay Ravat
Earth and Environmental Sciences Research Data
This data set contains Central and Eastern U.S. Magnetic Anomaly, DRTP, Tilt Derivative, and Analytic Signal Amplitude Products ultimately derived from Ravat, D., Finn, C., Hill, P., Kucks, R., Phillips, J., Blakely, R., Bouligand, C., Sabaka, T., Elshayat, A., Aref, A., and Elawadi, E., 2009, A preliminary, full spectrum, magnetic anomaly grid of the United States with improved long wavelengths for studying continental dynamics--A website for distribution of data: U.S. Geological Survey Open- File Report 2009–1258, 2 p.
Precise Zircon U-Pb Dating Of The Mesoproterozoic Gawler Large Igneous Province, South Australia, Elizabeth A. Jagodzinski, Anthony J. Reid, James L. Crowley, Claire E. Wade, Stacey Curtis
Precise Zircon U-Pb Dating Of The Mesoproterozoic Gawler Large Igneous Province, South Australia, Elizabeth A. Jagodzinski, Anthony J. Reid, James L. Crowley, Claire E. Wade, Stacey Curtis
Geosciences Faculty Publications and Presentations
The Mesoproterozoic Gawler Range Volcanics and Benagerie Volcanic Suite of the Gawler Craton and Curnamona Province, South Australia, together with associated intrusive magmatism, define an intracontinental, subaerial large igneous province (LIP) preserving an estimated 110 000 km3 of volcanic rock, which hosts one of the world's largest orebodies, the Fe oxide-Cu-Au-U deposit at Olympic Dam, and numerous other related Cu-Au deposits. New high-precision Chemical Abrasion Isotope Dilution Thermal Ionization Mass Spectrometry (CA-TIMS) U-Pb dates on volcanic zircons allow for regional correlations between stratigraphic units of the GRV and BVS, and an understanding of how magmatic styles, temperatures, composition and …
Silicon And Oxygen In Earth’S Core: Applications Of Machine Learning To Metal-Silicate Equilibria And Core Formation, Ruben Keane
Silicon And Oxygen In Earth’S Core: Applications Of Machine Learning To Metal-Silicate Equilibria And Core Formation, Ruben Keane
WWU Honors College Senior Projects
Within Earth’s core, light elements (Si, O, C, S, N, H) are known to make up a small fraction of the total mass of the core with respect to heavy elements. The degree to which these elements exist in the cores of terrestrial planets have geophysical and geochemical implications, most notably the presence of core convection and a geodynamo, thermal conductivity within the core, and core temperature. Comparison of the composition of chondrites to Earth’s mantle composition and the Preliminary Reference Earth Model have given an estimation of about 10 % light elements in Earth’s core. The concentrations of each …
Drivers Of Spatiotemporal Patterns Of Surface Water Inputs In A Catchment At The Rain-Snow Transition Zone Of The Water-Limited Western United States, E. Trujillo, J. Mcnamara
Drivers Of Spatiotemporal Patterns Of Surface Water Inputs In A Catchment At The Rain-Snow Transition Zone Of The Water-Limited Western United States, E. Trujillo, J. Mcnamara
Geosciences Faculty Publications and Presentations
Spatial and temporal dynamics of rainfall and snowmelt (i.e., surface water inputs, SWI) control soil moisture, groundwater recharge, and streamflow at annual, seasonal, and event scales. In the rain-snow transition zone, comprising a large portion of the mountainous western United States, there is limited understanding of the sensitivity of spatiotemporal SWI dynamics across hydrologically variable water years (WYs). We modeled rainfall and snowpack dynamics in a small headwater catchment (1.8 km2) spanning the rain-snow transition in southwestern Idaho, USA, for two hydrologically distinct WYs (2011 and 2014). In wet WY 2011 and dry WY 2014, total precipitation drove …
The Geology Of El Paso, William Cornell, Diane Doser, Richard Langford, Joshua Villalobos, Jason Ricketts
The Geology Of El Paso, William Cornell, Diane Doser, Richard Langford, Joshua Villalobos, Jason Ricketts
Books & Monographs
The Geology of El Paso describes the history of El Paso, Texas and its surrounding region from the Precambrian formation of the continent to the modern use of geologic resources. This book is written in an easy to digest format, with definitions or links for specific geologic terms and references for further reading. It reviews the formation and evolution of local landmark features such as the Franklin Mountains, Cerro Cristo Rey, and the Sierra de Juarez. Fossils and stratigraphic units of the El Paso area are described as well as important geologic features. The book puts the events that shaped …
Historical Tsunami Observability For Izu–Bonin–Mariana Sources, Walter Szeliga, Rachelle Reisinger, Breanyn T. Macinnes
Historical Tsunami Observability For Izu–Bonin–Mariana Sources, Walter Szeliga, Rachelle Reisinger, Breanyn T. Macinnes
Geological Sciences Faculty Scholarship
The Izu–Bonin–Mariana Subduction System (IBM) is one of the longest subduction zones in the world with no instrumental history of shallow focus, great earthquakes (Mw > 8). Over the last 50 years, researchers have speculated on the reason for the absence of large magnitude, shallow seismicity on this plate interface, exploring factors from plate age to convergence rate. We approach the question from a different point of view: what if the IBM has hosted great earthquakes and no documentable evidence was left? To address the question of observability, we model expected tsunami wave heights from nine great earthquake scenarios on the …
The Isotropic And Anisotropic Structure Of Antarctica From Seismic Inversion, Zhengyang Zhou
The Isotropic And Anisotropic Structure Of Antarctica From Seismic Inversion, Zhengyang Zhou
Arts & Sciences Electronic Theses and Dissertations
This dissertation utilizes multiple techniques of earthquake tomography to investigate the seismic structure of the crust and mantle beneath Antarctica. The isotropic structure of the Antarctic crust and upper mantle is now constrained by several seismic studies, but until now few studies have investigated the anisotropic structure. Therefore, in this study, I focus on the anisotropic structure, which is crucial information to understanding current or historic deformation and flow patterns, as well as the organic process of Antarctica. I use the data from the seismic stations deployed on the Antarctica continent during the past 20 years, as well as other …
Uncertainty Of Icesat-2 Atl06- And Atl08-Derived Snow Depths For Glacierized And Vegetated Mountain Regions, Ellyn M. Enderlin, Colten M. Elkin, Madeline Gendreau, H.P. Marshall, Shad O'Neel, Christopher Mcneil, Caitlyn Florentine, Louis Sass
Uncertainty Of Icesat-2 Atl06- And Atl08-Derived Snow Depths For Glacierized And Vegetated Mountain Regions, Ellyn M. Enderlin, Colten M. Elkin, Madeline Gendreau, H.P. Marshall, Shad O'Neel, Christopher Mcneil, Caitlyn Florentine, Louis Sass
Geosciences Faculty Publications and Presentations
Seasonal snow melt dominates the hydrologic budget across a large portion of the globe. Snow accumulation and melt vary over a broad range of spatial scales, preventing accurate extrapolation of sparse in situ observations to watershed scales. The lidar onboard the Ice, Cloud, and land Elevation, Satellite (ICESat-2) was designed for precise mapping of ice sheets and sea ice, and here we assess the feasibility of snow depth-mapping using ICESat-2 data in more complex and rugged mountain landscapes. We explore the utility of ATL08 Land and Vegetation Height and ATL06 Land Ice Height differencing from reference elevation datasets in two …
Cascadia Subduction Zone Earthquake Vertical Ground Acceleration Investigation And Potential Impact On Bridges In The Pacific Northwest, Rachel C. Bassil
Cascadia Subduction Zone Earthquake Vertical Ground Acceleration Investigation And Potential Impact On Bridges In The Pacific Northwest, Rachel C. Bassil
Civil and Environmental Engineering Master's Project Reports
The effects of vertical ground accelerations during subduction zone earthquakes currently are not sufficiently understood. There are numerous case studies and evidence that effects of vertical ground accelerations can significantly impact the performance of bridges during a seismic event, but most previous research has been focused on shallow crustal earthquakes. Current bridge design codes provide little guidance for accounting for vertical ground accelerations in seismic design, in part because additional information is needed about the characteristics of vertical ground motions during Cascadia Subduction Zone (CSZ) earthquakes in the Pacific Northwest.
For this study, recorded seismic data from recent subduction zone …
(R1978) Heated Laminar Vertical Jet Of Psudoplastic Fluids-Against Gravity, Manisha Patel, M. G. Timol
(R1978) Heated Laminar Vertical Jet Of Psudoplastic Fluids-Against Gravity, Manisha Patel, M. G. Timol
Applications and Applied Mathematics: An International Journal (AAM)
A heated laminar jet of Pseudo-plastic fluid flowing vertically upwards from a long narrow slit into a region of the same fluid which is at a rest and at a uniform temperature is considered. The governing non-linear Partial differential equations (PDEs) for the defined flow problem are transformed into non-linear ordinary differential equations using the effective similarity technique-one parameter deductive group theory method. The obtained non-linear coupled Ordinary differential equations are solved and the results are presented by graphs. The effect of the Prandtl number and Grashof number on the velocity and temperature of the jet flow is discussed. Also, …
Using Ground Penetrating Radar To Investigate Controls On Pedogenic Calcium Carbonate Distribution In Dryland Critical Zones, Nohemi Valenzuela Garay
Using Ground Penetrating Radar To Investigate Controls On Pedogenic Calcium Carbonate Distribution In Dryland Critical Zones, Nohemi Valenzuela Garay
Open Access Theses & Dissertations
Caliche or pedogenic calcium carbonate (CaCO3) layers are a common feature of arid soils, but the environmental controls on their distribution are not fully understood. Caliche layers are thought to play an important role in shallow subsurface water storage and movement, due to their water retention capacity and ability to impede vertical water transport (Hennessy et al., 1983). Therefore, caliche distribution and stability play a role in controlling water distribution in arid lands. However, due to its largely subsurface nature, caliche can be difficult to investigate and map without significant effort. I hypothesize that noninvasive geophysical methods, such as ground-penetrating …
Reprocessing Groundwater Resistivity Surveys In The Lower Mesilla Basin, New Mexico, And Texas, Leslie Bernal
Reprocessing Groundwater Resistivity Surveys In The Lower Mesilla Basin, New Mexico, And Texas, Leslie Bernal
Open Access Theses & Dissertations
The Mesilla Basin is part of the Rio Grande Basin System. Its northern boundary is definedby the Doña Ana Mountains in New Mexico and to the south by Sierra San Blas, Sierra Almirez, and Sierra La Candelaria in Mexico, where the basin changes its name to Conejos-Médanos. It supplies water for irrigation and public use to the cities of Las Cruces, NM, El Paso, TX, and Ciudad Juárez, Mexico. The southern part of the basin in the U.S. territory, known as the Lower Mesilla Basin, is bounded to the east by the Franklin Mountains, to the west by the Potrillo …
Hydrothermal Alteration Targeting And Geophysical Mineral Exploration Of Eureka And Sylvanite Mining Districts, Southwest New Mexico, Kenneth Singh
Hydrothermal Alteration Targeting And Geophysical Mineral Exploration Of Eureka And Sylvanite Mining Districts, Southwest New Mexico, Kenneth Singh
Open Access Theses & Dissertations
As part of the southwestern North American porphyry copper province, mining of natural resources in New Mexico has historically played a crucial role in economic development for over 150 years including this project area in the Little Hatchet Mountains. The northern half of the Little Hatchet Mountains lies in Grant County and includes the Eureka Mining District (EMD) whereas the southern half is in Hidalgo County and includes the Sylvanite Mining District (SMD), 38 miles southeast of Lordsburg. The EMD, a copper and silver-lead mining district from 1880-1961, had a total estimated production from the Laramide veins of 2.9 million …
Using Anisotropy Of Magnetic Susceptibility (Ams) To Identify A Tectonic Lineation In The Pulo Do Lobo Formation In The Southern Iberian Shear Zone Near Aracena, Spain, Devin Levang
Theses and Dissertations
The Southern Iberian Shear Zone (SISZ) is a Variscan-aged suture representing the closure of a small ocean basin during the Carboniferous. The SISZ is bounded on either side by the well-studied, relatively homogeneous Beja-Acebuches Metabasites (BAM) and the complex and heterogeneous accretionary metasedimentary rocks of the Pulo do Lobo (PdL). The SISZ underwent a combination of shortening and lateral shearing known as transpression. Despite a very well-developed tectonic foliation, kinematic interpretation in the PdL is made difficult by a lack of easily identifiable lineations. Anisotropy of magnetic susceptibility (AMS), a geophysical technique measuring the relative anisotropy of magnetic susceptibility axes …
Statistical Analysis Of Aquifer Hydraulic Properties By A Continuous Pumping Tomography Test: Application To The Boise Hydrogeophysical Research Site, Kan Bun Cheng, Gedeon Dagan, Warren Barrash, Michael Cardiff, Avinoam Rabinovich
Statistical Analysis Of Aquifer Hydraulic Properties By A Continuous Pumping Tomography Test: Application To The Boise Hydrogeophysical Research Site, Kan Bun Cheng, Gedeon Dagan, Warren Barrash, Michael Cardiff, Avinoam Rabinovich
Geosciences Faculty Publications and Presentations
Characterizing aquifer heterogeneity is paramount for accurate flow and transport modeling. In this work, we present a new approach for statistical analysis of hydraulic properties in continuous pumping tomography tests of a phreatic aquifer. The method entails determining equivalent hydraulic conductivity (Keq), specific storage (Ss,eq), and specific yield (Sy,eq) at many locations in the field and then calculating statistical moments of the equivalent properties, assuming they are random space variables. Equivalent properties are defined as the ones pertinent to a homogeneous aquifer for which the head time …
The Formation Of The 8˚20’ N Seamount Chain, East Pacific Rise, Dorsey Wanless
The Formation Of The 8˚20’ N Seamount Chain, East Pacific Rise, Dorsey Wanless
Geosciences Faculty Publications and Presentations
Near-axis seamounts provide a unique setting to investigate three-dimensional mantle processes associated with the formation of new oceanic crust and lithosphere. Here, we investigate the characteristics and evolution of the 8˚20’N Seamount Chain, a lineament of seamounts that extends ~ 175 km west of the East Pacific Rise (EPR) axis, just north of the fracture zone of the Siqueiros Transform Fault. Shipboard gravity, magnetic, and bathymetric data acquired in 2016 are utilized to constrain models of seamount emplacement and evolution. Geophysical observations indicate that these seamounts formed during four distinct episodes of volcanism coinciding with changes in regional plate motion …
Predictions And Drivers Of Sub-Reach-Scale Annual Streamflow Permanence For The Upper Missouri River Basin: 1989–2018, Kendra E. Kaiser
Predictions And Drivers Of Sub-Reach-Scale Annual Streamflow Permanence For The Upper Missouri River Basin: 1989–2018, Kendra E. Kaiser
Geosciences Faculty Publications and Presentations
The presence of year-round surface water in streams (i.e., streamflow permanence) is an important factor for identifying aquatic habitat availability, determining the regulatory status of streams, managing land use change, allocating water resources, and designing scientific studies. However, accurate, high resolution, and dynamic prediction of streamflow permanence that accounts for year-to-year variability at a regional extent is a major gap in modeling capability. Herein, we expand and adapt the U.S. Geological Survey (USGS) PRObability of Streamflow PERmanence (PROSPER) model from its original implementation in the Pacific Northwest (PROSPERPNW) to the upper Missouri River basin (PROSPERUM), a …
Emplacement Of The Franklin Large Igneous Province And Initiation Of The Sturtian Snowball Earth, Mark D. Schmitz
Emplacement Of The Franklin Large Igneous Province And Initiation Of The Sturtian Snowball Earth, Mark D. Schmitz
Geosciences Faculty Publications and Presentations
During the Cryogenian (720 to 635 Ma ago) Snowball Earth glaciations, ice extended to sea level near the equator. The cause of this catastrophic failure of Earth’s thermostat has been unclear, but previous geochronology has suggested a rough coincidence of glacial onset with one of the largest magmatic episodes in the geological record, the Franklin large igneous province. U-Pb geochronology on zircon and baddeleyite from sills associated with the paleo-equatorial Franklin large igneous province in Arctic Canada record rapid emplacement between 719.86 ± 0.21 and 718.61 ± 0.30 Ma ago, 0.9 to 1.6 Ma before the onset of widespread glaciation. …
The Impact Of Contact Geometry On Sea Ice Stress And Fracture At The Scale Of Ice Floes, Michael J. May
The Impact Of Contact Geometry On Sea Ice Stress And Fracture At The Scale Of Ice Floes, Michael J. May
Dartmouth College Master’s Theses
Observations of stress and strain at the scale of ice floes are necessary to fill a gap in our understanding of sea ice mechanical behavior. Current climate and ice dynamics models represent ice mechanical properties using stress-strain relationships largely determined at laboratory-scale (<1m) or from regional-scale (10+km) deformation observations. The former scale does not include all mechanisms of deformation operating in the ice pack; the latter aggregates multiple modes of deformation into non-physical fluid analogies. The Sea Ice Dynamics Experiment (SIDEx) was run in Feb-Mar 2021 to fill this gap, observing stress and strain at the scale of sea ice failure processes. Here we present stress sensor observations. Stress gages (N=31) were deployed over a 4.5km2 area in the southern Beaufort Sea to observe in-situ stress. These data were analyzed in the context of deformation observations from satellite imagery and local laser and radar interferometers to explain the drivers of sea ice stress variations before and after fracture. Three case studies between 14 March and 24 March, during which fractures propagated through …1m)>
Hydrogeologic Investigation Of A Covered Karst Terrain, Joseph Peter Honings
Hydrogeologic Investigation Of A Covered Karst Terrain, Joseph Peter Honings
LSU Doctoral Dissertations
Increasing demand for water for agricultural use within the Dougherty Plain of the Southeastern United States has depleted surface water bodies. In karstic landscapes, such as the Dougherty Plain in southwest Georgia where the linkages between surface and ground waters are close, there is a need to understand the physical characteristics of the subsurface that allow these close linkages. Having a better understanding of the subsurface characteristics will aid numerical modeling efforts that underpin policy decisions and economic analyses. Two common features on this karstic landscape are draws and geographically isolated wetlands. Using LiDAR, aerial imagery, and ground-penetrating radar, this …
Approaches To Model Non-Uniqueness And Site Complexity For Non-Invasive Shear-Wave Depth Profiling, Christopher Boucher
Approaches To Model Non-Uniqueness And Site Complexity For Non-Invasive Shear-Wave Depth Profiling, Christopher Boucher
Electronic Thesis and Dissertation Repository
Shear-wave velocity (VS) depth profiling and associated seismic site classifications were performed at 15 sites across Metro Vancouver, British Columbia using passive seismic and surface wave methods. Inversion model parameters are constrained at each site using nearby geodata in combination with developing regression models of shear-wave velocity with depth for three primary stratigraphic units. Statistical methods such as a Bayesian Information Criterion are applied post-inversion to evaluate models between and within varying parameterizations. Data evaluation metrics, including the use of microtremor horizontal-to-vertical spectral ratios (MHVSRs), are applied to identify two common deviations from the simple case of normally dispersive laterally …
Infrasonic Gliding Reflects A Rising Magma Column At Mount Etna (Italy), Mariangela Sciotto, Leighton M. Watson, Andrea Cannata, Massimo Cantarero, Emanuela De Beni, Jeffrey B. Johnson
Infrasonic Gliding Reflects A Rising Magma Column At Mount Etna (Italy), Mariangela Sciotto, Leighton M. Watson, Andrea Cannata, Massimo Cantarero, Emanuela De Beni, Jeffrey B. Johnson
Geosciences Faculty Publications and Presentations
Infrasound is increasing applied as a tool to investigate magma dynamics at active volcanoes, especially at open-vent volcanoes, such as Mt. Etna (Italy), which are prodigious sources of infrasound. Harmonic infrasound signals have been used to constrain crater dimensions and track the movement of magma within the shallow plumbing system. This study interprets the remarkable systematic change in monotonic infrasound signals preceding a lava fountaining episode at Mt. Etna on 20 February 2021. We model the changing tones (0.7 to 3 Hz fundamental frequency) as a rise in the magma column from 172 ± 25 m below the crater rim …
Upper-Plate Structure And Tsunamigenic Faults Near The Kodiak Islands, Alaska, Usa, Marlon D. Ramos, Lee M. Liberty, Peter J. Haeussler, Robert Humphreys
Upper-Plate Structure And Tsunamigenic Faults Near The Kodiak Islands, Alaska, Usa, Marlon D. Ramos, Lee M. Liberty, Peter J. Haeussler, Robert Humphreys
Geosciences Faculty Publications and Presentations
The Kodiak Islands lie near the southern terminus of the 1964 Great Alaska earthquake rupture area and within the Kodiak subduction zone segment. Both local and trans-Pacific tsunamis were generated during this devastating megathrust event, but the local tsunami source region and the causative faults are poorly understood. We provide an updated view of the tsunami and earthquake hazard for the Kodiak Islands region through tsunami modeling and geophysical data analysis. Using seismic and bathymetric data, we characterize a regionally extensive seafloor lineament related to the Kodiak shelf fault zone, with focused uplift along a 50-km-long portion of the newly …
Review Article: Global Monitoring Of Snow Water Equivalent Using High-Frequency Radar Remote Sensing, Hans-Peter Marshall
Review Article: Global Monitoring Of Snow Water Equivalent Using High-Frequency Radar Remote Sensing, Hans-Peter Marshall
Geosciences Faculty Publications and Presentations
Seasonal snow cover is the largest single component of the cryosphere in areal extent, covering an average of 46 × 106 km2 of Earth's surface (31 % of the land area) each year, and is thus an important expression and driver of the Earth's climate. In recent years, Northern Hemisphere spring snow cover has been declining at about the same rate (∼ −13 % per decade) as Arctic summer sea ice. More than one-sixth of the world's population relies on seasonal snowpack and glaciers for a water supply that is likely to decrease this century. Snow is also …
Low-Volume Magmatism Linked To Flank Deformation On Isla Santa Cruz, Galápagos Archipelago, Using Cosmogenic 3He Exposure And 40Ar/39Ar Dating Of Fault Scarps And Lavas, D. M. Schwartz, K. Harpp, M. D. Kurz, E. Wilson, R. Van Kirk
Low-Volume Magmatism Linked To Flank Deformation On Isla Santa Cruz, Galápagos Archipelago, Using Cosmogenic 3He Exposure And 40Ar/39Ar Dating Of Fault Scarps And Lavas, D. M. Schwartz, K. Harpp, M. D. Kurz, E. Wilson, R. Van Kirk
Geosciences Faculty Publications and Presentations
Isla Santa Cruz is a volcanic island located in the central Galápagos Archipelago. The island’s northern and southern flanks are deformed by E–W-trending normal faults not observed on the younger Galápagos shields, and Santa Cruz lacks the large summit calderas that characterize those structures. To construct a chronology of volcanism and deformation on Santa Cruz, we employ 40Ar/39Ar geochronology of lavas and 3He exposure dating of fault scarps from across the island. The combination of Ar–Ar dating with in situ-produced cosmogenic exposure age data provides a powerful tool to evaluate fault chronologies. The 40 …
Airborne Snowsar Data At X And Ku Bands Over Boreal Forest, Alpine And Tundra Snow Cover, Hans-Peter Marshall
Airborne Snowsar Data At X And Ku Bands Over Boreal Forest, Alpine And Tundra Snow Cover, Hans-Peter Marshall
Geosciences Faculty Publications and Presentations
The European Space Agency SnowSAR instrument is a side-looking, dual-polarised (VV/VH), X/Ku band synthetic aperture radar (SAR), operable from various sizes of aircraft. Between 2010 and 2013, the instrument was deployed at several sites in Northern Finland, Austrian Alps and northern Canada. The purpose of the airborne campaigns was to measure the backscattering properties of snow-covered terrain to support the development of snow water equivalent retrieval techniques using SAR. SnowSAR was deployed in Sodankylä, Northern Finland, for a single flight mission in March 2011 and 12 missions at two sites (tundra and boreal forest) in the winter of 2011–2012. Over …
Nsf Supported Socio-Environmental Research: How Do Crosscutting Programs Affect Research Funding, Publication, And Citation Patterns?, Kendra E. Kaiser, Anna E. Braswell, Megan L. Fork
Nsf Supported Socio-Environmental Research: How Do Crosscutting Programs Affect Research Funding, Publication, And Citation Patterns?, Kendra E. Kaiser, Anna E. Braswell, Megan L. Fork
Geosciences Faculty Publications and Presentations
Recognizing the continued human domination of landscapes across the globe, social-ecological systems (SES) research has proliferated, necessitating interdisciplinary collaborations. Although interdisciplinary research started gaining traction in academic settings close to 50 years ago, formal frameworks for SES research did not develop until the late 1990s. The first National Science Foundation (NSF) funding mechanism specifically for interdisciplinary SES research began in 2001 and the SES-specific Coupled Natural Human (CNH) Systems program began in 2007. We used data on funded NSF projects from 2000 to 2015 to examine how SES research was funded, where the research is published, and the scholarly impact …
Diverse Magmatic Evolutionary Trends Of The Northern Andes Unraveled By Paleocene To Early Eocene Detrital Zircon Geochemistry, James L. Crowley
Diverse Magmatic Evolutionary Trends Of The Northern Andes Unraveled By Paleocene To Early Eocene Detrital Zircon Geochemistry, James L. Crowley
Geosciences Faculty Publications and Presentations
The Paleocene-early Eocene continental magmatic arc (PECMA) in the Northern Andes is an example of arc magmatism following a major collisional event. This arc formed after the arc-continent collision between the Caribbean Plate and the South American continental margin at ca. 72 Ma. We used detrital zircon LA-ICP-MS and CA-ID-TIMS geochronology and geochemistry to complement the limited plutonic record of the PECMA and better characterize the PECMA's magmatic evolution. Zircon geochronology and their respective trace element geochemistry were analyzed from Paleocene-early Eocene strata of the Bogotá Formation in the foreland region. Our results show that after the collision of the …