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Limits To Coseismic Landslides Triggered By Cascadia Subduction Zone Earthquakes, Alex R.R. Grant, William T. Struble, Sean R. LaHusen 2022 U.S. Geological Survey

Limits To Coseismic Landslides Triggered By Cascadia Subduction Zone Earthquakes, Alex R.R. Grant, William T. Struble, Sean R. Lahusen

United States Geological Survey: Staff Publications

Landslides are a significant hazard and dominant feature throughout the landscape of the Pacific Northwest. However, the hazard and risk posed by coseismic landslides triggered by great Cascadia Subduction Zone (CSZ) earthquakes is highly uncertain due to a lack of local and global data. Despite a wealth of other geologic evidence for past earthquakes on the Cascadia Subduction Zone, no landslides have been definitively linked to such earthquakes, even in areas otherwise highly susceptible to failure. While shallow landslides may not leave a lasting topographical signature in the landscape, there are thousands of deep-seated landslides in Cascadia, and these deposits …


Mgrre_Thinsections_05_A_34, MGRRE 2022 Western Michigan University

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Very High Middle Miocene Surface Productivity On The U.S. Mid-Atlantic Shelf Amid Glacioeustatic Sea Level Variability, Marci M. Robinson, Harry J. Dowsett, Timothy D. Herbert 2022 U.S. Geological Survey

Very High Middle Miocene Surface Productivity On The U.S. Mid-Atlantic Shelf Amid Glacioeustatic Sea Level Variability, Marci M. Robinson, Harry J. Dowsett, Timothy D. Herbert

United States Geological Survey: Staff Publications

The Miocene Climatic Optimum (MCO) provides important insights into how the climate system operates under elevated temperatures and atmospheric CO2 levels. Few western North Atlantic paleotemperature or paleoecological records exist from the MCO, despite their importance for understanding both regional and global climate dynamics. Here we present quantitative MCO paleoecological data from the western North Atlantic, specifically from the Baltimore Gas & Electric (BG&E) marine sediment core from southern Maryland, USA. We examine alkenones and planktic foraminifera and document the first sea surface temperature (SST) and productivity estimates for the MCO and the Middle Miocene Climate Transition (MMCT) from …


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 2022 EnviTrace, Carbon Solutions LLC

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 …


Neural Net Detection Of Seismic Features Related To Gas Hydrates And Free Gas Accumulations On The Northern U.S. Atlantic Margin, Urmi Majumdar, Nathaniel C. Miller, Carolyn D. Ruppel 2022 Woods Hole Oceanographic Institution, U.S. Geological Survey

Neural Net Detection Of Seismic Features Related To Gas Hydrates And Free Gas Accumulations On The Northern U.S. Atlantic Margin, Urmi Majumdar, Nathaniel C. Miller, Carolyn D. Ruppel

United States Geological Survey: Staff Publications

Bottom-simulating reflections (BSRs) that sometimes mark the base of the gas hydrate stability zone in marine sediments are often identified based on the reverse polarity reflections that cut across stratigraphic layering in seismic amplitude data. On the northern U.S. Atlantic margin (USAM) between Cape Hatteras and Hudson Canyon, legacy seismic data have revealed pronounced BSRs south of the deepwater extension of Hudson Canyon and more subtle ones from offshore Delaware south to Cape Hatteras, where the reflections sometimes follow stratigraphic layering. Using high-resolution seismic data acquired during the 2018 Mid-Atlantic Resource Imaging Experiment and a supervised neural net, we identify …


Mgrre_Thinsections_05_A_33, MGRRE 2022 Western Michigan University

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Establishment Of Invasive Black Carp (Mylopharyngodon Piceus) In The Mississippi River Basin: Identifying Sources And Year Classes Contributing To Recruitment, Gregory W. Whitledge, Patrick T. Kroboth, Duane C. Chapman, Quinton E. Phelps, Wes Sleeper, Jennifer Bailey, Jill A. Jenkins 2022 Southern Illinois University School of Medicine

Establishment Of Invasive Black Carp (Mylopharyngodon Piceus) In The Mississippi River Basin: Identifying Sources And Year Classes Contributing To Recruitment, Gregory W. Whitledge, Patrick T. Kroboth, Duane C. Chapman, Quinton E. Phelps, Wes Sleeper, Jennifer Bailey, Jill A. Jenkins

United States Geological Survey: Staff Publications

Black Carp (Mylopharyngodon piceus) was imported to the USA to control aquaculture pond snails. This species has escaped captivity and occurs in parts of the Mississippi River, several tributaries, and floodplain lakes, which is concerning due to potential competition with native fishes and predation on native mussels, many of which are imperiled. However, Black Carp captures have primarily been incidental by commercial fishers, and evidence of reproduction in the wild is limited. The objectives of this study were to assess relative abundance of aquaculture- origin and wild Black Carp using ploidy and otolith stable isotope analysis, identify spatial …


Mgrre_Thinsections_05_A_32, MGRRE 2022 Western Michigan University

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Multi-Omics Responses In Tree Swallow (Tachycineta Bicolor) Nestlings From The Maumee Area Of Concern, Maumee River, Ohio, Chi Yen Tseng, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Natalie Karouna-Renier, Cole W. Matson 2022 Baylor University

Multi-Omics Responses In Tree Swallow (Tachycineta Bicolor) Nestlings From The Maumee Area Of Concern, Maumee River, Ohio, Chi Yen Tseng, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Natalie Karouna-Renier, Cole W. Matson

United States Geological Survey: Staff Publications

A multi-omics approach was utilized to identify altered biological responses and functions, and to prioritize contaminants to assess the risks of chemical mixtures in the Maumee Area of Concern (AOC), Maumee River, OH, USA. The Maumee AOC is designated by the United States Environmental Protection Agency as having significant beneficial use impairments, including degradation of fish and wildlife populations, bird or animal deformities or reproduction problems, and loss of fish and wildlife habitat. Tree swallow (Tachycineta bicolor) nestlings were collected at five sites along the Maumee River, which included wastewater treatment plants (WWTPs) and industrial land-use sites. Polychlorinated …


Mgrre_Thinsections_05_A_31, MGRRE 2022 Western Michigan University

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A Systematic Review And Meta-Analysis Of The Direct Effects Of Nutrients On Corals, Eileen M. Nalley, Lillian J. Tuttle, Emily E. Conklin, Alexandria L. Barkman, Devynn M. Wulstein, Madeline C. Schmidbauer, Megan J. Donahue 2022 University of Hawai'i at Mānoa

A Systematic Review And Meta-Analysis Of The Direct Effects Of Nutrients On Corals, Eileen M. Nalley, Lillian J. Tuttle, Emily E. Conklin, Alexandria L. Barkman, Devynn M. Wulstein, Madeline C. Schmidbauer, Megan J. Donahue

United States Geological Survey: Staff Publications

Chronic exposure of coral reefs to elevated nutrient conditions can modify the performance of the coral holobiont and shift the competitive interactions of reef organisms. Many studies have nowquantified the links between nutrients and coral performance, but fewhave translated these studies to directly address coastal water quality standards. To address this management need, we conducted a systematic review of peer-reviewed studies, public reports, and gray literature that examined the impacts of dissolved inorganic nitrogen (DIN: nitrate, nitrite, and ammonium) and dissolved inorganic phosphorus (DIP: phosphate) on scleractinian corals. The systematic review resulted in 47 studies with comparable data on coral …


Mgrre_Thinsections_05_A_30, MGRRE 2022 Western Michigan University

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Coastalimagelib: An Open- Source Python Package For Creating Common Coastal Image Products, Maile P. McCann, Dylan L. Anderson, Christopher R. Sherwood, Brittany Bruder, A. Spicer Bak, Katherine L. Brodie 2022 University of Southern California, U.S. Army Engineer Research and Development Center

Coastalimagelib: An Open- Source Python Package For Creating Common Coastal Image Products, Maile P. Mccann, Dylan L. Anderson, Christopher R. Sherwood, Brittany Bruder, A. Spicer Bak, Katherine L. Brodie

United States Geological Survey: Staff Publications

CoastalImageLib is a Python library that produces common coastal image products intended for quantitative analysis of coastal environments. This library contains functions to georectify and merge multiple oblique camera views, produce statistical image products for a given set of images, and create subsampled pixel instruments for use in bathymetric inversion, surface current estimation, run-up calculations, and other quantitative analyses. This package intends to be an open-source broadly generalizable front end to future coastal imaging applications, ultimately expanding user accessibility to optical remote sensing of coastal environments. This package was developed and tested on data collected from the Argus Tower, a …


Mgrre_Thinsections_05_A_29, MGRRE 2022 Western Michigan University

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Transcriptome Signatures Of Wastewater Effluent Exposure In Larval Zebrafish Vary With Seasonal Mixture Composition In An Effluent-Dominated Stream, Emma B. Meade, Luke R. Iwanowicz, Nicklaus Neureuther, Gregory H. LeFevre, Dana W. Kolpin, Hui Zhi, Shannon M. Meppelink, Rachael F. Lane, Angela Schmoldt, Aurash Mohaimani, Olaf Mueller, Rebecca D. Klaper 2022 University of Wisconsin-Milwaukee

Transcriptome Signatures Of Wastewater Effluent Exposure In Larval Zebrafish Vary With Seasonal Mixture Composition In An Effluent-Dominated Stream, Emma B. Meade, Luke R. Iwanowicz, Nicklaus Neureuther, Gregory H. Lefevre, Dana W. Kolpin, Hui Zhi, Shannon M. Meppelink, Rachael F. Lane, Angela Schmoldt, Aurash Mohaimani, Olaf Mueller, Rebecca D. Klaper

United States Geological Survey: Staff Publications

Wastewater treatment plant (WWTP) effluent-dominated streams provide critical habitat for aquatic and terrestrial organisms but also continually expose them to complex mixtures of pharmaceuticals that can potentially impair growth, behavior, and reproduction. Currently, few biomarkers are available that relate to pharmaceutical-specific mechanisms of action. In the experiment reported in this paper, zebrafish (Danio rerio) embryos at two developmental stages were exposed to water samples from three sampling sites (0.1 km upstream of the outfall, at the effluent outfall, and 0.1 km below the outfall) during base-flow conditions from two months (January and May) of a temperate-region effluent-dominated stream …


Speleothems In Sandstone Crevice And Boulder Caves Of The Elbe River Canyon, Czech Republic, Jiří Adamovič, Jaroslav Kukla, Michal Filippi, Roman Skála, Noemi Mészárosová 2022 Institute of Geology, Czech Acad. Sci.

Speleothems In Sandstone Crevice And Boulder Caves Of The Elbe River Canyon, Czech Republic, Jiří Adamovič, Jaroslav Kukla, Michal Filippi, Roman Skála, Noemi Mészárosová

International Journal of Speleology

A variety of speleothems are present in crevice and boulder caves developed in Cretaceous sandstones of the Elbe River Canyon in northern Czech Republic. A set of complementary instrumental mineralogical methods was applied to characterize the speleothems and cave dripwaters, including X-ray powder diffraction, scanning electron microscopy and microanalysis, Raman spectroscopy and optical emission spectrometry. Four morphological types were distinguished and characterized in terms of their mineral and chemical composition: 1, rusty brown mud-dominated coatings with micro-gours, composed of a mixture of clay minerals; 2, white “chalky” coatings (moonmilk) composed of calcite with minor gypsum; 3, cauliflower-shaped coralloids composed of …


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 2022 Colorado State University, Now at U.S. Geological Survey

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 …


Mgrre_Thinsections_05_A_28, MGRRE 2022 Western Michigan University

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No abstract provided.


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 2022 Colorado State University, U.S. Geological Survey

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 …


Mgrre_Thinsections_05_A_27, MGRRE 2022 Western Michigan University

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No abstract provided.


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