Open Access. Powered by Scholars. Published by Universities.®

Earth Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 14101 - 14130 of 59516

Full-Text Articles in Earth Sciences

Sinistral Shear During Middle Jurassic Emplacement Of The Matancilla Plutonic Complex In Northern Chile (25.4◦ S) As Evidence Of Oblique Plate Convergence During The Early Andean Orogeny, S. P. Mavor, J. S. Singleton, G. Heuser, R. Gomila, N. M. Seymour, S. Williams, G. Arancibia Sep 2022

Sinistral Shear During Middle Jurassic Emplacement Of The Matancilla Plutonic Complex In Northern Chile (25.4◦ S) As Evidence Of Oblique Plate Convergence During The Early Andean Orogeny, S. P. Mavor, J. S. Singleton, G. Heuser, R. Gomila, N. M. Seymour, S. Williams, G. Arancibia

United States Geological Survey: Staff Publications

Arc magmatism in a continental subduction zone facilitates rheological weakening of the rigid upper plate, and can accommodate the partitioned trench-parallel component of oblique subduction into an intra-arc shear zone. We document a shear zone at latitude 25.4◦ S near Taltal, Chile that was associated with intrusion of the Matancilla Plutonic Complex at ~169 Ma to evaluate intra-arc deformation and possible tectonic plate configurations during this time period. Polyphase folding of Paleozoic metasedimentary rocks is overprinted by mylonitic fabrics that are most extensive in a zone up to 1.4 km wide in the thermal aureole of the granodioritic Matancilla …

Go to article

Using Whole-Brain Diffusion Tensor Analysis To Evaluate White Matter Structural Correlates Of Delayed Visuospatial Memory And One-Week Motor Skill Retention In Nondemented Older Adults: A Preliminary Study, Jennapher Lingo Vangilder, Maurizio Bergamino, Andrew Hooyman, Megan C. Fitzhugh, Corianne Rogalsky, Jill C. Stewart, Scott C. Beeman, Sydney Y. Schaefer Sep 2022

Using Whole-Brain Diffusion Tensor Analysis To Evaluate White Matter Structural Correlates Of Delayed Visuospatial Memory And One-Week Motor Skill Retention In Nondemented Older Adults: A Preliminary Study, Jennapher Lingo Vangilder, Maurizio Bergamino, Andrew Hooyman, Megan C. Fitzhugh, Corianne Rogalsky, Jill C. Stewart, Scott C. Beeman, Sydney Y. Schaefer

Faculty Publications

Skill retention is important for motor rehabilitation outcomes. Recent work has demonstrated that delayed visuospatial memory performance may predict motor skill retention in older and neuropathological populations. White matter integrity between parietal and frontal cortices may explain variance in upper-extremity motor learning tasks and visuospatial processes. We performed a whole-brain analysis to determine the white matter correlates of delayed visuospatial memory and one-week motor skill retention in nondemented older adults. We hypothesized that better frontoparietal tract integrity would be positively related to better behavioral performance. Nineteen participants (age>58) completed diffusion-weighted imaging, then a clinical test of delayed visuospatial memory …

Go to article

Mgrre_Thinsections_05_A_28, Mgrre Sep 2022

Mgrre_Thinsections_05_A_28, Mgrre

Thin Sections

No abstract provided.

Go to article

Sinistral Shear During Middle Jurassic Emplacement Of The Matancilla Plutonic Complex In Northern Chile (25.4◦ S) As Evidence Of Oblique Plate Convergence During The Early Andean Orogeny, S.P. Mavor, J.S. Singleton, G. Heuser, R Gomila, N.M. Seymour, S. Williams, G. Arancibia Sep 2022

Sinistral Shear During Middle Jurassic Emplacement Of The Matancilla Plutonic Complex In Northern Chile (25.4◦ S) As Evidence Of Oblique Plate Convergence During The Early Andean Orogeny, S.P. Mavor, J.S. Singleton, G. Heuser, R Gomila, N.M. Seymour, S. Williams, G. Arancibia

United States Geological Survey: Staff Publications

component of oblique subduction into an intra-arc shear zone. We document a shear zone at latitude 25.4◦ S near Taltal, Chile that was associated with intrusion of the Matancilla Plutonic Complex at ~169 Ma to evaluate intra-arc deformation and possible tectonic plate configurations during this time period. Polyphase folding of Paleozoic metasedimentary rocks is overprinted by mylonitic fabrics that are most extensive in a zone up to 1.4 km wide in the thermal aureole of the granodioritic Matancilla pluton, where contact metamorphic andalusite porphyroblasts are synkinematic with fabric development. Mylonite in metasedimentary rocks is overprinted by a ~130 Ma …

Go to article

Mgrre_Thinsections_05_A_27, Mgrre Sep 2022

Mgrre_Thinsections_05_A_27, Mgrre

Thin Sections

No abstract provided.

Go to article

Mgrre_Thinsections_05_A_26, Mgrre Sep 2022

Mgrre_Thinsections_05_A_26, Mgrre

Thin Sections

No abstract provided.

Go to article

Mgrre_Thinsections_05_A_25, Mgrre Sep 2022

Mgrre_Thinsections_05_A_25, Mgrre

Thin Sections

No abstract provided.

Go to article

Discovering Hidden Geothermal Signatures Using Non-Negative Matrix Factorization With Customized K-Means Clustering, V.V. Vesselinov, B. Ahmmed, M.K. Mudunuru, J.D. Pepin, E.R. Burns, D.L. Siler, S. Karra, R.S. Middleton Sep 2022

Discovering Hidden Geothermal Signatures Using Non-Negative Matrix Factorization With Customized K-Means Clustering, V.V. Vesselinov, B. Ahmmed, M.K. Mudunuru, J.D. Pepin, E.R. Burns, D.L. Siler, S. Karra, R.S. Middleton

United States Geological Survey: Staff Publications

Discovery of hidden geothermal resources is challenging. It requires the mining of large datasets with diverse data attributes representing subsurface hydrogeological and geothermal conditions. The commonly used play fairway analysis approach typically incorporates subject-matter expertise to analyze regional data to estimate geothermal characteristics and favorability. We demonstrate an alternative approach based on machine learning (ML) to process a geothermal dataset from southwest New Mexico (SWNM). The study region includes low- and medium-temperature hydrothermal systems. Several of these systems are not well characterized because of insufficient existing data and limited past explorative work. This study discovers hidden patterns and relations in …

Go to article

Mgrre_Thinsections_05_A_24, Mgrre Sep 2022

Mgrre_Thinsections_05_A_24, Mgrre

Thin Sections

No abstract provided.

Go to article

Mgrre_Thinsections_05_A_23, Mgrre Sep 2022

Mgrre_Thinsections_05_A_23, Mgrre

Thin Sections

No abstract provided.

Go to article

Enrofloxacin And Sulfamethoxazole Sorption On Carbonized Leonardite: Kinetics, Isotherms, Influential Effects, And Antibacterial Activity Toward S. Aureus Atcc 25923, Chanat Chokejaroenrat, Chainarong Sakulthaew, Khomson Satchasataporn, Daniel D. Snow, Tarik E. Ali, Mohammed A. Assiri, Apichon Watcharenwong, Saksit Imman, Nopparat Suriyachai, Torpong Kreetachat Sep 2022

Enrofloxacin And Sulfamethoxazole Sorption On Carbonized Leonardite: Kinetics, Isotherms, Influential Effects, And Antibacterial Activity Toward S. Aureus Atcc 25923, Chanat Chokejaroenrat, Chainarong Sakulthaew, Khomson Satchasataporn, Daniel D. Snow, Tarik E. Ali, Mohammed A. Assiri, Apichon Watcharenwong, Saksit Imman, Nopparat Suriyachai, Torpong Kreetachat

Nebraska Water Center: Faculty Publications

Excessive antibiotic use in veterinary applications has resulted in water contamination and potentially poses a serious threat to aquatic environments and human health. The objective of the current study was to quantify carbonized leonardite (cLND) adsorption capabilities to remove sulfamethoxazole (SMX)- and enrofloxacin (ENR)-contaminated water and to determine the microbial activity of ENR residuals on cLND following adsorption. The cLND samples prepared at 450oC and 850oC (cLND450 and cLND550, respectively) were evaluated for structural and physical characteristics and adsorption capabilities based on adsorption kinetics and isotherm studies. The low pyrolysis temperature of cLND resulted in a …

Go to article

Mgrre_Thinsections_05_A_22, Mgrre Sep 2022

Mgrre_Thinsections_05_A_22, Mgrre

Thin Sections

No abstract provided.

Go to article

Mgrre_Thinsections_05_A_21, Mgrre Sep 2022

Mgrre_Thinsections_05_A_21, Mgrre

Thin Sections

No abstract provided.

Go to article

Combining Freestanding Ferroelectric Perovskite Oxides With Two-Dimensional Semiconductors For High Performance Transistors, Sergio Puebla, Thomas Pucher, Victor Rouco, Gabriel Sanchez-Santolino, Yong Xie, Victor Zamora, Fabian A. Cuellar, Federico J. Mompean, Carlos Leon, Carlos O. Island, Mar Garcia-Hernandez, Jacobo Santamaria, Carmen Munuera, Andres Castellanos-Gomez Sep 2022

Combining Freestanding Ferroelectric Perovskite Oxides With Two-Dimensional Semiconductors For High Performance Transistors, Sergio Puebla, Thomas Pucher, Victor Rouco, Gabriel Sanchez-Santolino, Yong Xie, Victor Zamora, Fabian A. Cuellar, Federico J. Mompean, Carlos Leon, Carlos O. Island, Mar Garcia-Hernandez, Jacobo Santamaria, Carmen Munuera, Andres Castellanos-Gomez

Physics & Astronomy Faculty Research

We demonstrate the fabrication of field-effect transistors based on single-layer MoS2 and a thin layer of BaTiO3 (BTO) dielectric, isolated from its parent epitaxial template substrate. Thin BTO provides an ultrahigh-κ gate dielectric effectively screening Coulomb scattering centers. These devices show mobilities substantially larger than those obtained with standard SiO2 dielectrics and comparable with values obtained with hexagonal boron nitride, a dielectric employed for fabrication of high-performance two-dimensional (2D) based devices. Moreover, the ferroelectric character of BTO induces a robust hysteresis of the current vs gate voltage characteristics, attributed to its polarization switching. This hysteresis is strongly suppressed when the …

Go to article

Geomorphic And Paleoclimatic Implications Of Glacial Extent Records In The Sierra Nevada Del Cocuy, Colombia During Termination 1, Jordan Nickerson Herbert Sep 2022

Geomorphic And Paleoclimatic Implications Of Glacial Extent Records In The Sierra Nevada Del Cocuy, Colombia During Termination 1, Jordan Nickerson Herbert

Dartmouth College Master’s Theses

Reconstructions of past glacial extents using geomorphic mapping and cosmogenic dating provide an opportunity to infer past climates. A record of the past extents of tropical mountain glaciers is particularly useful because there are few other means to reconstruct past temperatures in high-altitude, low-latitude locations. The tropics play an outsized role in mediating global climate, yet there is a lack of understanding of how the tropics may have influenced past climate changes such as the most recent deglaciation (Termination 1, ~18–11.7 ka). Improving reconstructions of tropical mountain glaciers will aid in understanding the role of the tropics in the global …

Go to article

The Effects Of Estradiol-17Β On The Sex Reversal, Survival, And Growth Of Green Sunfish Lepomis Cyanellus, Chad N. Teal, Daniel J. Schill, Susan B. Fogelson, Colby M. Roberts, Kevin Fitzsimmons, Javan M. Bauder, William T. Stewart, Scott A. Bonar Sep 2022

The Effects Of Estradiol-17Β On The Sex Reversal, Survival, And Growth Of Green Sunfish Lepomis Cyanellus, Chad N. Teal, Daniel J. Schill, Susan B. Fogelson, Colby M. Roberts, Kevin Fitzsimmons, Javan M. Bauder, William T. Stewart, Scott A. Bonar

United States Geological Survey: Staff Publications

The feminization of green sunfish Lepomis cyanellus could expand their utility as a game fish or aquacultured species by preventing overcrowding and precocious reproduction in stocked systems. Feminization of green sunfish could also help elucidate information on their sex determination system. We report the feminization of green sunfish cohorts via oral administration of estradiol-17β (E2) during early development. A low-dose (100 E2 mg per kg of diet) and a high-dose (150 E2 mg per kg of diet) experimental E2 treatment were fed to juvenile green sunfish from 30 to 90 days post-hatch. Fish were subsequently evaluated for any treatment effect …

Go to article

Mgrre_Thinsections_05_A_20, Mgrre Sep 2022

Mgrre_Thinsections_05_A_20, Mgrre

Thin Sections

No abstract provided.

Go to article

Mgrre_Thinsections_05_A_19, Mgrre Sep 2022

Mgrre_Thinsections_05_A_19, Mgrre

Thin Sections

No abstract provided.

Go to article

Landslide Susceptibility Map Of Johnson County, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch, William C. Haneberg Sep 2022

Landslide Susceptibility Map Of Johnson County, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch, William C. Haneberg

Contract Reports--KGS

The purpose of this map is to identify landslide-prone areas in Johnson County in order to provide the public, as well as local and state government agencies, with information about where landslides are likely to occur. This map represents geomorphic-based susceptibility modeling that focuses on physical slope characteristics and morphology, the quality of which is dependent on data accuracy and resolution of terrain models. The availability of high-resolution (5-ft digital elevation model) lidar derived datasets allows for the generation of terrain elevation derivatives such as hillshades, slope, aspect, curvature, and roughness, as well as identification of existing landslide deposits. These …

Go to article

Landslide Susceptibility Map Of Floyd County, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch, William C. Haneberg Sep 2022

Landslide Susceptibility Map Of Floyd County, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch, William C. Haneberg

Contract Reports--KGS

The purpose of this map is to identify landslide-prone areas in Floyd County in order to provide the public, as well as local and state government agencies, with information about where landslides are likely to occur. This map represents geomorphic-based susceptibility modeling that focuses on physical slope characteristics and morphology, the quality of which is dependent on data accuracy and resolution of terrain models. The availability of high-resolution (5-ft digital elevation model) lidar derived datasets allows for the generation of terrain elevation derivatives such as hillshades, slope, aspect, curvature, and roughness, as well as identification of existing landslide deposits. These …

Go to article

Landslide Susceptibility Map Of Magoffin County, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch, William C. Haneberg, Ashton A. Killen Sep 2022

Landslide Susceptibility Map Of Magoffin County, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch, William C. Haneberg, Ashton A. Killen

Contract Reports--KGS

The purpose of this map is to identify landslide-prone areas in Magoffin County, Kentucky, in order to provide the public, as well as local and state government agencies, with information about where landslides are likely to occur. This map represents geomorphic-based susceptibility modeling that focuses on physical slope characteristics and morphology, the quality of which is dependent on data accuracy and resolution of terrain models. The availability of high-resolution (5-ft digital elevation model) lidar derived datasets allows for the generation of terrain elevation derivatives such as hillshades, slope, aspect, curvature, and roughness, as well as identification of existing landslide deposits. …

Go to article

Landslide Susceptibility Map Of Pike County, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch, William C. Haneberg Sep 2022

Landslide Susceptibility Map Of Pike County, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch, William C. Haneberg

Contract Reports--KGS

The purpose of this map is to identify landslide-prone areas in Pike County in order to provide the public, as well as local and state government agencies, with information about where landslides are likely to occur. This map represents geomorphic-based susceptibility modeling that focuses on physical slope characteristics and morphology, the quality of which is dependent on data accuracy and resolution of terrain models. The availability of high-resolution (5-ft digital elevation model) lidar derived datasets allows for the generation of terrain elevation derivatives such as hillshades, slope, aspect, curvature, and roughness, as well as identification of existing landslide deposits. These …

Go to article

Climate Change Alters Aging Patterns Of Reservoir Aquatic Habitats, Leandro E. Miranda, Nicky M. Faucheux Sep 2022

Climate Change Alters Aging Patterns Of Reservoir Aquatic Habitats, Leandro E. Miranda, Nicky M. Faucheux

United States Geological Survey: Staff Publications

Two slow-moving developments are threatening reservoir aquatic habitats globally: aging and climate change. These events are projected to transform reservoir aquatic habitats in various and often unpredictable ways. Aging affects in-lake habitats directly, whereas climate change affects both in-lake and off-lake conditions. Climate change is expected to accelerate and, in some instances, possibly decelerate aging. Aging can be indexed as functional age, an index that signals the position of a reservoir along its lifespan relying on inlake descriptors of aquatic habitat. Using existing habitat datasets and climate projections, we developed semi-quantitative predictions about the effect of climate change on reservoir …

Go to article

Mgrre_Thinsections_05_A_18, Mgrre Sep 2022

Mgrre_Thinsections_05_A_18, Mgrre

Thin Sections

No abstract provided.

Go to article

Mgrre_Thinsections_05_A_17, Mgrre Sep 2022

Mgrre_Thinsections_05_A_17, Mgrre

Thin Sections

No abstract provided.

Go to article

Mgrre_Thinsections_05_A_16, Mgrre Sep 2022

Mgrre_Thinsections_05_A_16, Mgrre

Thin Sections

No abstract provided.

Go to article

Sediment Source Fingerprinting As An Aid To Large-Scale Landscape Conservation And Restoration: A Review For The Mississippi River Basin, Zhen Xu, Patrick Belmont, Janice Brahney, Allen C. Gellis Sep 2022

Sediment Source Fingerprinting As An Aid To Large-Scale Landscape Conservation And Restoration: A Review For The Mississippi River Basin, Zhen Xu, Patrick Belmont, Janice Brahney, Allen C. Gellis

United States Geological Survey: Staff Publications

Reliable quantitative information on sediment sources to rivers is critical to mitigate contamination and target conservation and restoration actions. However, for large-scale river basins, determination of the relative importance of sediment sources is complicated by spatiotemporal variability in erosional processes and sediment sources, heterogeneity in sediment transport and deposition, and a paucity of sediment monitoring data. Sediment source fingerprinting is an increasingly adopted field-based technique that identifies the nature and relative source contribution of sediment transported in waterways. Notably, sediment source fingerprinting provides information that is independent of other field, modeling, or remotely sensed techniques. However, the diversity in sampling, …

Go to article

Mgrre_Thinsections_05_A_15, Mgrre Sep 2022

Mgrre_Thinsections_05_A_15, Mgrre

Thin Sections

No abstract provided.

Go to article

Mgrre_Thinsections_05_A_14, Mgrre Sep 2022

Mgrre_Thinsections_05_A_14, Mgrre

Thin Sections

No abstract provided.

Go to article

Recovery Of Soil Microbial Diversity And Functions Along A Tropical Montane Forest Disturbance Gradient, Renee Sniegocki, Jessica B. Moon, Abigail L. Rutrough, Jude Gireneus, Jaya Seelan Sathiya Seelan, Michael C. Farmer, David C. Weindorf, Kusum Naithani Sep 2022

Recovery Of Soil Microbial Diversity And Functions Along A Tropical Montane Forest Disturbance Gradient, Renee Sniegocki, Jessica B. Moon, Abigail L. Rutrough, Jude Gireneus, Jaya Seelan Sathiya Seelan, Michael C. Farmer, David C. Weindorf, Kusum Naithani

Biological Sciences Faculty Publications and Presentations

Logging and forest conversion are occurring at alarming rates in tropical forests. These disturbances alter soil microbial community structure and functions. While direct links between changes in soil properties, such as pH and microbial community structure are well established, the indirect effects of logging and forest conversion on soil microbial community structure and functions are poorly understood. We used a space-for-time substitution to investigate the changes in soil microbial diversity and functions across a forest recovery gradient in the tropical montane forests of northern Borneo. We used surface (top 5 cm) soil to assess soil physicochemical and microbial (next-generation DNA …

Go to article

First Prev Next Last