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Quantifying Model Structural Uncertainty Using Airborne Electromagnetic Data, Burke J. Minsley, Nathan Leon Foks, Paul A. Bedrosian 2021 United States Geological Survey

Quantifying Model Structural Uncertainty Using Airborne Electromagnetic Data, Burke J. Minsley, Nathan Leon Foks, Paul A. Bedrosian

USGS Staff -- Published Research

The ability to quantify structural uncertainty in geological models that incorporate geophysical data is affected by two primary sources of uncertainty: geophysical parameter uncertainty and uncertainty in the relationship between geophysical parameters and geological properties of interest. Here, we introduce an open-source, trans-dimensional Bayesian Markov chain Monte Carlo (McMC) algorithm GeoBIPy—Geophysical Bayesian Inference in Python—for robust uncertainty analysis of time-domain or frequency-domain airborne electromagnetic (AEM) data. The McMC algorithm provides a robust assessment of geophysical parameter uncertainty using a trans-dimensional approach that lets the AEM data inform the level of model complexity necessary by allowing the number of ...


New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor And Sample Photographs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. McAvoy 2021 University of New Hampshire, Durham

New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor And Sample Photographs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign - Seafloor and Sample Photographs and Sediment Data " contains photographs of the seafloor from sampling locations, photographs of the sediment samples, and grain size data from a major field campaign conducted in 2016- 2017 and from the UNH Ocean Engineering 972 Hydrographic Field Course classes in 2012, 2014, and 2018. In total, sixteen one-day cruises provided 150 samples for grain size analysis. The database provides complete descriptions for each sample including identification, station and sample characteristics, sediment classifications, grain size statistics, and grain size distribution. Presented here are tables with the ...


New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign - Stations And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. McAvoy 2021 University of New Hampshire, Durham

New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign - Stations And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign - Stations and Sediment Data" contains sediment grain size data from a major field campaign conducted in 2016-2017 and from the UNH Ocean Engineering 972 Hydrographic Field Course classes in 2012, 2014, and 2018. In total, sixteen one-day cruises provided 150 samples for grain size analysis. The database provides complete descriptions for each sample including identification, station and sample characteristics, sediment classifications, grain size statistics, and grain size distribution. Samples were analyzed with standard sieve and pipette analyses after Folk (1980). The sediment grain size classifications include: CMECS (Coastal and Marine ...


New Hampshire Continental Shelf Historical Geophysical Database: 1971 To 2015 - Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. McAvoy, Maxlimer Coromoto Vallee-Anziani 2021 University of New Hampshire, Durham

New Hampshire Continental Shelf Historical Geophysical Database: 1971 To 2015 - Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Data Catalog

The UNH CCOM/JHC "New Hampshire Continental Shelf Historical Geophysical Database: 1971 to 2015 - Sediment Data" contains sediment grain size data and classifications from studies conducted between 1971 and 2015. In total, grain size data was available for 725 bottom sediment samples. Included are sample identification information, station and sample characteristics, sediment classifications, grain size statistics, and grain size distribution. Not all of these parameters were available for every study. Samples were analyzed with standard sieve and pipette analyses after Folk (1980). The sediment grain size classifications include: CMECS (Coastal and Marine Ecological Classification Standard; FGDC, 2012); Gradistat (Blot and ...


The Effects Of Heterogeneities And Syn-Deformational Partial Melting On Rock Strength Evolution And Melt Migration, Nicole Wagner 2021 The University of Akron

The Effects Of Heterogeneities And Syn-Deformational Partial Melting On Rock Strength Evolution And Melt Migration, Nicole Wagner

Williams Honors College, Honors Research Projects

In nature, the segregation of granitic melts at the source may be controlled by fabric and compositional heterogeneities in the source rock, such as foliation and lineation. To investigate the influence of foliation/lineation orientation and composition on rock strength and melt interconnectivity, I performed a series of experiments on cores of a fine-grained gneiss (Gneiss Minuti) and a fine-grained muscovite-bearing quartzite (Moine Thrust quartzite). These rocks were cored at six primary orientations parallel, 45 degrees, and perpendicular to the foliation and lineation and were deformed at a constant temperature of 900°C, pressure of ~2 GPa, and strain rate ...


New Hampshire Continental Shelf Geophysical Database: Vibracore Logs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. McAvoy, Maxlimer Coromoto Vallee-Anziani 2021 University of New Hampshire CCOM/JHC, Durham

New Hampshire Continental Shelf Geophysical Database: Vibracore Logs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: Vibracore Logs and Sediment Data" contains complete core logs and sediment grain size data from twenty‐three vibracores taken on the New Hampshire shelf in 1984 and 1988. During the present program, the original core descriptions, data, and photographs were verified and significantly expanded, synthesized, and presented in uniform core logs.The vibracore logs, sediment data, and the depositional environments are discussed in detail in Ward et al., 2021 (https://dx.doi.org/10.34051/p/2021.26).


New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Zachary S. McAvoy 2021 University of New Hampshire CCOM/JHC, Durham

New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs” was developed by the University of New Hampshire (UNH) Center for Coastal and Ocean Mapping/Joint Hydrographic Center (CCOM/JHC). The field campaign was conducted to provide ground truth for surficial geology maps for the continental shelf off New Hampshire (NH) and focused on the inner shelf between the coast and the Isles of Shoals. Station locations were chosen where high-resolution bathymetry was available, including multibeam echosounder (MBES) surveys conducted by the UNH CCOM/JHC Hydrographic Field Course (Ocean Engineering 972), MBES surveys by the NOAA National Ocean ...


Variations In Produced Water Chemistry And Relation To Regional Geology And Production In The Marcellus Shale, Northcentral West Virginia, Jonathan M. Brady 2021 West Virginia University

Variations In Produced Water Chemistry And Relation To Regional Geology And Production In The Marcellus Shale, Northcentral West Virginia, Jonathan M. Brady

Graduate Theses, Dissertations, and Problem Reports

An investigation of 74 Marcellus Shale wells across northcentral West Virginia indicates changes in produced water chemistry and quantity can be related to geologic conditions based on well logs and core data. These changes are determined by reviewing multiple produced water analyses for individual wells for periods up to ten years. Results show variations among the areas in this study. From west to east across central Harrison County to central Taylor County, then north into Monongalia County, gamma-ray logs show increasing intensity, especially in the middle and lower Marcellus. XRD mineralogy from core data shows increasing clay content from west ...


Effect Of Oxidative Breakers On Organic Matter Degradation, Contaminant Mobility And Critical Mineral Release During Shale-Fracturing Fluid Interactions In The Marcellus Shale, Shaun Donmoyer 2021 West Virginia University

Effect Of Oxidative Breakers On Organic Matter Degradation, Contaminant Mobility And Critical Mineral Release During Shale-Fracturing Fluid Interactions In The Marcellus Shale, Shaun Donmoyer

Graduate Theses, Dissertations, and Problem Reports

Production of oil and gas from organic-rich shale formations has become viable through advancements in multi-stage hydraulic fracturing. The decline of shale gas production after the initial days of fracturing operations coupled with falling oil and gas prices, has pushed industry operators to use new chemical additives as an attempt to increase hydrocarbon production. The implementation of highly reactive fracturing fluids that include strong oxidizing agents, pose as a potential solution to increase well productivity. Strong oxidizing chemicals commonly known in fracturing operations as breakers, are used to improve the viscosity of gel-based fluids after the proppant is transported into ...


Policy Analysis Of Emissions Cap And Trade: The United State And The European Union, Drew Bealby 2021 Fort Hays State University

Policy Analysis Of Emissions Cap And Trade: The United State And The European Union, Drew Bealby

Master's Theses

Effects of climate change are appearing each day therefore proactive steps need to be made to reduce these effects. The National Aeronautics and Space Administration (NASA) notes that humans producing greenhouse gases (GHGs) such as carbon dioxide (CO2), methane, and nitrous oxide are the main reason the Earth’s overall temperature is rising (NASA 2019). A policy analysis was done on the European Union Emissions Trading Scheme (EU ETS) along with comparisons to the United States’ emissions policies that are in place currently. The European Union (E.U.) itself is both an economic and political union of 27 countries ...


A Karst Feature Prediction Model For Prince Of Wales Island, Alaska Based On High Resolution Lidar Imagery, Alexander Lyles 2021 Fort Hays State University

A Karst Feature Prediction Model For Prince Of Wales Island, Alaska Based On High Resolution Lidar Imagery, Alexander Lyles

Master's Theses

Investigation into surface karst formation is significant to hazard prediction, hydrogeologic drainage, and land management. Southeast Alaska contains over 600,000 acres of mapped carbonate bedrock, and some of the fastest recorded karst dissolution in the world. The objectives of this study are to develop and compare multiple semi-automated models to map and delineate karst features from bare-earth LiDAR imagery using ArcGIS Desktop 10.7, and to apply a preliminary geostatistical analysis of sinkhole morphometric parameters to highlight potential spatial patterns of karst evolution on Prince of Wales Island, Alaska. A semi-automated approach of mapping karst features provides a dataset ...


Martian Spectroscopy: Laboratory Calibration Of The Perseverance Rover’S Mastcam-Z And Photometric Investigation Of Mars-Analog Ferric-Coated Sand, Kristiana Lapo 2021 Western Washington University

Martian Spectroscopy: Laboratory Calibration Of The Perseverance Rover’S Mastcam-Z And Photometric Investigation Of Mars-Analog Ferric-Coated Sand, Kristiana Lapo

WWU Graduate School Collection

The Mars 2020 rover Perseverance will search for signs of past habitability and biosignatures after landing in Jezero Crater in February 2021. Spectroscopy is a vital tool for planetary remote sensing and Perseverance is equipped with Mastcam-Z, a stereoscopic, zoom-enabled, multispectral imager that can acquire true color images with red, green, and blue (RGB) color filters, and visible- to near-infrared images with 12 narrowband science filters between 400 and 1100 nm. Mastcam-Z will provide operational support for the rover as well as directly contribute to Perseverance’s geologic investigations. Given the integral role of Mastcam-Z in the Mars 2020 mission ...


Marine Ecosystem Response To Late Pleistocene Rapid Climate Change In The Salish Sea, Alex Victor Hernandez 2021 Western Washington University

Marine Ecosystem Response To Late Pleistocene Rapid Climate Change In The Salish Sea, Alex Victor Hernandez

WWU Graduate School Collection

The ecologic response of marine invertebrates during collapse of the Cordilleran Ice-sheet through the Late Pleistocene has been insufficiently studied across the lowlands of northwestern Washington State and southern Fraser Valley, British Columbia. Assessment of the response of these nearshore marine assemblages to climatic shifts will improve our understanding of closely related modern taxa in analogous climate-stressed conditions. If we understand the former vulnerability of related genera, meaningful predictions may thus be provided for extant taxa in current and future time. In this thesis, I establish a compilation dataset of all relevant specimens collected within the Salish Sea and Puget ...


Structural Analysis And Interpretation Of Deformation Along The Keweenaw Fault System West Of Lake Gratiot, Keweenaw County, Michigan, Sophie A. Mueller 2021 Michigan Technological University

Structural Analysis And Interpretation Of Deformation Along The Keweenaw Fault System West Of Lake Gratiot, Keweenaw County, Michigan, Sophie A. Mueller

Dissertations, Master's Theses and Master's Reports

The Keweenaw fault is perhaps the most significant fault associated with the Midcontinent Rift System of the north-central United States. The fault, parallel to the south edge of the rift, has been interpreted as a rift-bounding normal fault that was inverted by subsequent compressional events, thrusting copper-bearing Portage Lake Volcanics (~ 1.1 Ga) over younger Jacobsville Sandstone. Geologic maps and cross sections published in the 1950s by the U. S. Geological Survey depict the fault with a well-defined, single, sinuous trace that is locally associated with smaller branch faults. Cross-sections from that time generally show a simple listric stratal geometry ...


Long-Term Geomorphic Effects Of The Glines Canyon Dam Removal On The Elwha River, Washington, Usa, Alyssa D. DeMott 2021 Central Washington University

Long-Term Geomorphic Effects Of The Glines Canyon Dam Removal On The Elwha River, Washington, Usa, Alyssa D. Demott

All Master's Theses

The Elwha River once provided vital habitat for a variety of salmonid species, but after two dams were emplaced on the river in the early 1900s, habitat diminished, and salmon populations declined. From 2011-2014, the dams were finally removed to restore the Elwha ecosystem. To understand the long-term geomorphic impacts of the Glines Canyon Dam removal on the Elwha River, I quantified changes in four parameters: in-channel large wood, main channel sinuosity, channel braiding, and sedimentation. High-resolution imagery from 2012-2020 was used to map large wood and digitize main and secondary river channels, and field surveys were completed at study ...


The Effect Of Coastal Landform Development On Decadal- To Millennial-Scale Longshore Sediment Fluxes: Evidence From The Holocene Evolution Of The Central Mid-Atlantic Coast, Usa - Sediment Core And Chronology Data, Justin L. Shawler, Christopher J. Hein, Chloe Obara, Mahina Robbins, Jennifer E. Connell, Sebastien Huot, Michael Fenster 2021 Virginia Institute of Marine Science

The Effect Of Coastal Landform Development On Decadal- To Millennial-Scale Longshore Sediment Fluxes: Evidence From The Holocene Evolution Of The Central Mid-Atlantic Coast, Usa - Sediment Core And Chronology Data, Justin L. Shawler, Christopher J. Hein, Chloe Obara, Mahina Robbins, Jennifer E. Connell, Sebastien Huot, Michael Fenster

Data

These data are sediment core, radiocarbon, and optically stimulated luminescence (OSL) data from the barrier islands and backbarrier lagoons, bays, and marshes of Assateague Island (VA, USA), Chincoteague Island (VA, USA), and Wallops Island (VA, USA). Vibracore data from Tom’s Cove, a backbarrier bay, were collected using a vibracore system with the ability to core through a ‘moonhole’ on a flat bottom boat. Geoprobe cores were collected using a track-mounted 66DT Geoprobe direct-push drill rig. Select samples from the sediment cores (associated with figures and tables in Shawler et al., 2021) were analyzed using a Beckman-Coulter Laser Diffraction Particle ...


Provenance Of Early Paleogene Strata In The Bighorn Basin (Wyoming, U.S.A.): Implications For Laramide Tectonism And Basin-Scale Stratigraphic Patterns, Jessica L. Welch 2021 Western Washington University

Provenance Of Early Paleogene Strata In The Bighorn Basin (Wyoming, U.S.A.): Implications For Laramide Tectonism And Basin-Scale Stratigraphic Patterns, Jessica L. Welch

WWU Graduate School Collection

The Bighorn Basin (Wyoming, U.S.A.) contains some of the best exposed and studied nonmarine early Paleogene strata. Over a century of research has produced a highly resolved record of early Paleogene terrestrial climatic and biotic change as well as extensive documentation of spatiotemporal variability in basin-scale stratigraphy. The basin also offers the opportunity to integrate these data with the uplift and erosional history of the Laramide uplifts that surround the Bighorn Basin. Herein we provide a comprehensive provenance analysis of the early Paleogene Fort Union and Willwood formations in the Bighorn Basin from paleocurrent measurements (n = 510 measurements ...


Analysis Of Vibracores From The New Hampshire Continental Shelf From 1984 And 1988, Larry G. Ward, Rachel C. Morrison, Zachary S. McAvoy, Maxlimer Coromoto Vallee-Anziani 2021 University of New Hampshire, Durham

Analysis Of Vibracores From The New Hampshire Continental Shelf From 1984 And 1988, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Center for Coastal and Ocean Mapping

During this study, the twenty-three vibracores taken in 1984 and 1988 were reexamined, original descriptions verified and significantly expanded, and the cores sampled to provide complete grain size data (i.e. the original sediment grain size analyses were limited). The vibracores were grouped by location with respect to major physiographic features (geoforms) or surficial sediment type including Offshore Marine-Modified Glacial Features (Drumlins and Lodgement Till Deposits), Northern Sand Body, Isles of Shoals, Nearshore Marine-Modified Glacial Features (Eskers and Drumlins), Nearshore Sheet Sand, and Offshore Seafloor Plain.

The Northern Sand Body (NSB), located near the Isles of Shoals ~10 km from ...


New Hampshire And Vicinity Continental Shelf: Sand And Gravel Resources, Larry G. Ward, Zachary S. McAvoy, Maxlimer Coromoto Vallee-Anziani 2021 University of New Hampshire, Durham

New Hampshire And Vicinity Continental Shelf: Sand And Gravel Resources, Larry G. Ward, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Center for Coastal and Ocean Mapping

The continental shelf off New Hampshire (NH) has extensive marine-modified glacial deposits and associated shoals. These features are potential targets for sand and gravel resources for beach nourishment and other efforts to build coastal resiliency. The distribution of sand and gravel deposits was evaluated based on the synthesis of relatively recent high-resolution bathymetry, new surficial sediment and geoform maps, and an extensive data archive that includes over ~1280 km of seismic profiles, ~750 grain size analyses, and 23 vibracores. This work heavily utilizes the results of previous research on mineral resources on the NH shelf by Birch (1984) and others ...


Surficial Geology Of The Continental Shelf Off New Hampshire: Morphologic Features And Surficial Sediment, Larry G. Ward, Zachary S. McAvoy, Maxlimer Coromoto Vallee-Anziani, Rachel C. Morrison 2021 University of New Hampshire CCOM/JHC, Durham

Surficial Geology Of The Continental Shelf Off New Hampshire: Morphologic Features And Surficial Sediment, Larry G. Ward, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani, Rachel C. Morrison

Center for Coastal and Ocean Mapping

The continental shelf off New Hampshire (NH) in the Western Gulf of Maine (WGOM) is extremely complex and includes extensive bedrock outcrops, marine-modified glacial deposits, marine-formed shoals, seafloor plains, and associated features that are composed of a range of sediment types from mud to gravel. Furthermore, the physiography and composition of the seafloor frequently changes dramatically over relatively short distances (tens of meters). The complexity of the WGOM seafloor results from the interplay of glaciations, sea-level fluctuations, and marine processes (waves and currents). High-resolution multibeam echosounder (MBES) bathymetry and backscatter surveys, along with ground truth consisting of archived seismic reflection ...


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