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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 ...


Inventory Of Rock Glaciers In The American West And Their Topography And Climate, Allison Reese Trcka 2020 Portland State University

Inventory Of Rock Glaciers In The American West And Their Topography And Climate, Allison Reese Trcka

Dissertations and Theses

Rock glaciers are flowing geomorphic landforms composed of an ice/debris mixture. A uniform rock glacier classification scheme was created for the western continental US, based on internationally recognized criteria, to merge the various regional published inventories. A total of 2249 rock glaciers (1564 active, 685 inactive) and 7852 features of interest were identified in 10 states (WA, OR, CA, ID, NV, UT, ID, MT, WY, CO, NM). Sulfur Creek rock glacier in Wyoming is the largest active rock glacier (2.39 km2). The mean area and elevation for active and inactive rock glaciers are 0.18 km2 ...


Hydrometeorological Factors Determining The Development Of Water Table Cave Patterns In High Alpine Zones. The Ordesa And Monte Perdido National Park, Ne Spain, Antonio González-Ramón, Jorge Jódar, José M. Samsó, Sergio Martos-Rosillo, Javier Heredia, Ane Zabaleta, Iñaki Antigüedad, Emilio Custodio, Luis J. Lambán 2020 Geological and Mining Institute of Spain

Hydrometeorological Factors Determining The Development Of Water Table Cave Patterns In High Alpine Zones. The Ordesa And Monte Perdido National Park, Ne Spain, Antonio González-Ramón, Jorge Jódar, José M. Samsó, Sergio Martos-Rosillo, Javier Heredia, Ane Zabaleta, Iñaki Antigüedad, Emilio Custodio, Luis J. Lambán

International Journal of Speleology

This study is focussed on the geomorphological characterization and the processes driving the evolution of the highest karst system in Western Europe, which is located in the Ordesa and Monte Perdido National Park (PNOMP), in the central-southern Pyrenees. The karst system does not seem to have a well-developed epikarst. The studied area shows a karst network of polygenic branchwork type in the vadose zone. Additionally, the explored karst conduits in the epiphreatic zone show a water table cave pattern that is different to the looping one, which is the expected cave pattern development for a karst located in a mountain ...


Crustal Evolution Of The New England Appalachians: The Rise And Fall Of A Long-Lived Orogenic Plateau, Ian Hillenbrand 2020 University of Massachusetts Amherst

Crustal Evolution Of The New England Appalachians: The Rise And Fall Of A Long-Lived Orogenic Plateau, Ian Hillenbrand

Masters Theses

The rise and demise of mountain belts, caused by growth, modification, or removal of the continental lithosphere are fundamental processes that influence almost all Earth systems. Understanding the nature, timing, and significance of active processes in the creation and evolution of modern mountain belts is challenged by a lack of middle crustal and lower crustal exposures. Analogues can be found in ancient orogens, whose deeply eroded roots offer a window into deeper processes, yet this record is complicated by overprinting events and complex deformational histories. Research presented herein constrains the tectonic history of multistage Appalachian Orogen, type locality of the ...


Magnetite Mineralization Of The Hammondville Pluton: Poly-Phase Kiruna Type Iocg Magnetite-Apatite Deposits In The Lyon Mountain Granite, Phillip Geer 2020 University of Massachusetts Amherst

Magnetite Mineralization Of The Hammondville Pluton: Poly-Phase Kiruna Type Iocg Magnetite-Apatite Deposits In The Lyon Mountain Granite, Phillip Geer

Masters Theses

Recent mapping of the Eagle Lake Quadrangle, NY, coupled with whole-rock geochemistry and microscopy has offered insight into the petrogenesis of the magnetite-apatite deposits of the Hammondville mining district in the eastern Adirondack Mountains. This study provides insight into the magmatic history of the ca. 1060-1050 Ma Lyon Mountain Granite (Hammondville Pluton) which is intimately related to, and hosts the deposits in this area. Magnetite seams are commonly surrounded by well layered magnetite gneiss, which typically parallel the seams, although in some outcrops appear to be slightly truncated by them. Mineralization is generally concordant with the weak layering found throughout ...


Implications And Significance Of Partial Melting On The Tectonic History Of The Eastern Adirondack Mountains, Claire Rose Pless 2020 University of Massachusetts Amherst

Implications And Significance Of Partial Melting On The Tectonic History Of The Eastern Adirondack Mountains, Claire Rose Pless

Doctoral Dissertations

The eastern Adirondack Mountains contain abundant exposures of high-grade metamorphic rocks. These exposures are interpreted to be a window into the mid/deep crust of an ancient, large, hot, long-duration orogen, allowing the Adirondack Mountains to be used as an analogue to the deep processes of modern orogens. Currently interpreted thermo-tectonic events in the eastern Adirondack Mountains include the ca. 1245-1220 Ma Elzevirian orogeny, the ca. 1190-1150 Ma Shawinigan orogeny, emplacement of the ca. 1150 Ma AMCG igneous suite, the ca. 1090-1050 Ma Ottawan orogeny, and a ca. 1050-1020 Ma extensional collapse phase. This dissertation focuses on six migmatite domains ...


3d Numerical Simulation-Based Targeting Of Skarn Type Mineralization Within The Xuancheng-Magushan Orefield, Middle-Lower Yangtze Metallogenic Belt, China, Xunyu Hu, Xiaohui Li, Feng Yuan, Simon M. Jowitt, Alison Ord, Rui Ye, Yue Li, Wenqiang Dai, Xiangling Li 2020 Hefei University of Technology

3d Numerical Simulation-Based Targeting Of Skarn Type Mineralization Within The Xuancheng-Magushan Orefield, Middle-Lower Yangtze Metallogenic Belt, China, Xunyu Hu, Xiaohui Li, Feng Yuan, Simon M. Jowitt, Alison Ord, Rui Ye, Yue Li, Wenqiang Dai, Xiangling Li

Geoscience Faculty Publications

Recent exploration has identified a series of Cu-Mo skarn deposits within the Xuancheng-Magushan orefield. The orefield forms part of the Nanling-Xuancheng mining district, which is located within the Middle-Lower Yangtze River Metallogenic Belt (MLYRMB) of central-eastern China. However, this area contains thick and widespread unprospective sedimentary cover sequences that have impeded traditional approaches to mineral exploration. This study presents the results of 3D numerical simulation modeling that identifies possible mineral exploration targets within the entire Xuancheng-Magushan orefield. This modeling enables the identification of unexplored areas with significant exploration potential that are covered by thick sedimentary sequences that cannot be easily ...


Coal Energy And Environmental Impacts: Introduction, Luis F. O. Silva, Amy L. Wolfe 2020 Universidad de La Costa, Colombia

Coal Energy And Environmental Impacts: Introduction, Luis F. O. Silva, Amy L. Wolfe

Kentucky Geological Survey Faculty Publications

No abstract provided.


Petrology Of The Gradational Intrusive Contact Between The Packsaddle Schist And The Town Mountain Granite, Enchanted Rock State Natural Area, Llano Uplift, Central Texas, Travis Galle 2020 Stephen F. Austin State University

Petrology Of The Gradational Intrusive Contact Between The Packsaddle Schist And The Town Mountain Granite, Enchanted Rock State Natural Area, Llano Uplift, Central Texas, Travis Galle

Electronic Theses and Dissertations

The Mesoproterozoic intrusive contact between the ~1.1 Ga anorogenic Town Mountain Granite and the ~1.3 Ga Packsaddle Schist is a gradational contact exhumed within the Llano uplift. This contact is exposed along the southeastern margin of the Enchanted Rock batholith in central Texas. Field observations, hand sample and thin section petrography, and handheld X-ray fluorescence analysis of hand samples were used to characterize the gradational nature of this contact at multiple scales. The style of gradation between the Town Mountain Granite and Packsaddle Schist varies throughout the study area, containing both injection and permeation. The complex relationships observed ...


Petrology Of The Gradational Intrusive Contact Between The Packsaddle Schist And The Town Mountain Granite, Enchanted Rock State Natural Area, Llano Uplift, Central Texas, Travis Galle 2020 Stephen F. Austin State University

Petrology Of The Gradational Intrusive Contact Between The Packsaddle Schist And The Town Mountain Granite, Enchanted Rock State Natural Area, Llano Uplift, Central Texas, Travis Galle

Student Publications

The Mesoproterozoic intrusive contact between the ~1.1 Ga anorogenic Town

Mountain Granite and the ~1.3 Ga Packsaddle Schist is a gradational contact

exhumed within the Llano uplift. This contact is exposed along the southeastern

margin of the Enchanted Rock batholith in central Texas. Field observations,

hand sample and thin section petrography, and handheld X-ray fluorescence

analysis of hand samples were used to characterize the gradational nature of this

contact at multiple scales. The style of gradation between the Town Mountain

Granite and Packsaddle Schist varies throughout the study area, containing both

injection and permeation. The complex relationships observed ...


The Age And Origin Of Precambrian Orthogneiss Of The Grouse Creek Block, Northern Utah And Southern Idaho, Skadi Kobe 2020 Utah State University

The Age And Origin Of Precambrian Orthogneiss Of The Grouse Creek Block, Northern Utah And Southern Idaho, Skadi Kobe

Fall Student Research Symposium 2020

New geochronologic and isotopic analyses from the Grouse Creek block (GC) provide insight into the assembly of western Laurentia during the late Archean to Paleoproterozoic and establish the influence of the GC in the evolution of Yellowstone-Snake River Plain hotspot magmatism in the central Snake River Plain. The GC is primarily exposed in the Albion-Raft River-Grouse Creek metamorphic core complex of northern Utah and southern Idaho and includes a complex assemblage of orthogneiss, schist, amphibolite, and metasediments intruded by Oligocene plutons and overlain by Cenozoic sedimentary units. Many investigations of the GC have focused on the structural evolution of the ...


New Research On A Case Of Linear Discontinuous Ground Deformation (Ldgd), Andrzej Kowalski, Bartosz Apanowicz, Piotr Polanin 2020 Central Mining Institute

New Research On A Case Of Linear Discontinuous Ground Deformation (Ldgd), Andrzej Kowalski, Bartosz Apanowicz, Piotr Polanin

Journal of Sustainable Mining

LSDS is defined as surface fissures, steps as well as structures formed by them in the form of stairs (several steps), thresholds, ditches, and flexure. The paper presents a case study of formed LSDS – the origin, and possible methods to assess its occurrence on the basis of the research carried out in the Central Mining Institute. The authors showed that the presence of LSDS leads not only to the horizontal deformation but also contributes to the formation of vertical curvatures of terrain that cause fissures in the near-surface layer of the rock mass in the areas with a thick layer ...


Surface Alteration In The Ölkelduháls, Nesjavellir, And Geysir Hydrothermal Systems, Iceland: Implications For Mars, Jordan Ludyan 2020 University of Wisconsin-Milwaukee

Surface Alteration In The Ölkelduháls, Nesjavellir, And Geysir Hydrothermal Systems, Iceland: Implications For Mars, Jordan Ludyan

Theses and Dissertations

Silica- and sulfate-rich deposits observed by Mars Exploration Rover (MER) Spirit near Home Plate, Gusev crater, Mars, indicate alteration of Mars basalt by a diverse array of hydrothermal fluids and processes. Constraining the precise fluid conditions present at the time of deposition for these deposits on Mars relies on investigations of terrestrial hydrothermal systems that produce similar mineral assemblages. Alteration products and fluids collected from the Ölkelduháls, Nesjavellir, and Geysir hydrothermal areas in southern Iceland cover a wide range of end-member and intermediate fluid and alteration environments, and provide a means to compare the secondary minerals produced from different hydrothermal ...


Sedimentology, Sequence Stratigraphy, And High-Precision U-Pb Age Constraints On The Late Paleozoic Ansilta Formation, Calingasta-Uspallata Basin, Nw Argentina, John Ethan Malone 2020 University of Wisconsin-Milwaukee

Sedimentology, Sequence Stratigraphy, And High-Precision U-Pb Age Constraints On The Late Paleozoic Ansilta Formation, Calingasta-Uspallata Basin, Nw Argentina, John Ethan Malone

Theses and Dissertations

The Ansilta Formation, located several kilometers east of the Astronomical Observatory El Leoncito near Barreal, San Juan Province, Argentina was deposited during the late Mississippian to early Pennsylvanian. This succession includes glacimarine, nearshore, and fluvial systems deposited at the mid-Carboniferous portion of the late Paleozoic ice age within the Calingasta—Uspallata Basin on the western margin of the Protoprecordillera. The lower member of the Ansilta Formation is equivalent to the nearby Leoncito, Majaditas, and Hoyada Verde formations, and is composed of diamictite, conglomerates, sandstones, pebbly mudstones, and laminated mudstone. Glacial environments are unique in that facies changes occur as a ...


Analyzing Strain Localization, Kinematic Partitioning And Fluid Flow In The Pulo Do Lobo Metasedimentary Rocks Along The Southern Iberian Shear Zone, Andalucia, Spain, Nancy Alejandra Carman 2020 University of Wisconsin-Milwaukee

Analyzing Strain Localization, Kinematic Partitioning And Fluid Flow In The Pulo Do Lobo Metasedimentary Rocks Along The Southern Iberian Shear Zone, Andalucia, Spain, Nancy Alejandra Carman

Theses and Dissertations

The Southern Iberian Shear Zone is a regional scale ductile shear zone that placed Beja-Acebuches metabasites over metapelite and quartzite rocks of the Pulo do Lobo Formation in a transpressional deformation with components of thrust and left-lateral movement. This project evaluates factors that contributed to strain localization at a variety of scales within the Pulo do Lobo formation, including lithologic variations, microstructures, and fluid flow. Additionally, microstructural data are used to test whether kinematic partitioning accompanied strain localization. Grain scale asymmetric indicators of sigma-type clasts, S-C fabrics, and asymmetric folds indicate dominant thrust motion. Strain intensity and metamorphic grade increase ...


Geochemistry, Petrology, And Palynology Of The Princess No. 3 Coal, Greenup County, Kentucky, Madison M. Hood, Cortland F. Eble, James C. Hower, Shifeng Dai 2020 University of Kentucky

Geochemistry, Petrology, And Palynology Of The Princess No. 3 Coal, Greenup County, Kentucky, Madison M. Hood, Cortland F. Eble, James C. Hower, Shifeng Dai

Center for Applied Energy Research Faculty Publications

The high volatile C bituminous-rank, Bolsovian-age Princess No. 3 coal, a correlative of the heavily-mined Hazard No. 7 coal and the Peach Orchard and Coalburg Lower Split coals, was investigated three sites at a mine in Greenup County, Kentucky. The coal exhibits a “dulling upwards” trend, with decreasing vitrinite and a greater tendency towards dull clarain and bone lithotypes towards the top of the coal. The relatively vitrinite-rich basal lithotype is marked by a dominance of lycopod tree spores. The palynology transitions upwards to a middle parting co-dominated by tree fern and small lycopod spores and an upper bench dominated ...


Impacts Of Environmental Conditions On Fleas In Black-Tailed Prairie Dog Burrows, Julia E. Poje, Tonie Rocke, Michael D. Samuel 2020 University of Wisconsin-Madison

Impacts Of Environmental Conditions On Fleas In Black-Tailed Prairie Dog Burrows, Julia E. Poje, Tonie Rocke, Michael D. Samuel

USGS Staff -- Published Research

Sylvatic plague, caused by the bacterium Yersinia pestis and transmitted by fleas, occurs in prairie dogs of the western United States. Outbreaks can devastate prairie dog communities, often causing nearly 100% mortality. Three competent flea vectors, prairie dog specialists Oropsylla hirsuta and O. tuberculata, and generalist Pulex simulans, are found on prairie dogs and in their burrows. Fleas are affected by climate, which varies across the range of black-tailed prairie dogs (Cynomys ludovicianus), but these effects may be ameliorated somewhat due to the burrowing habits of prairie dogs. Our goal was to assess how temperature and precipitation affect off-host flea ...


Interpretation Of Hydrogeologic Data To Support Groundwater Management, Bazile Groundwater Management Area, Northeast Nebraska, 2019—A Case Demonstration Of The Nebraska Geocloud, Christopher M. Hobza, Gregory V. Steele 2020 U.S. Geological Survey

Interpretation Of Hydrogeologic Data To Support Groundwater Management, Bazile Groundwater Management Area, Northeast Nebraska, 2019—A Case Demonstration Of The Nebraska Geocloud, Christopher M. Hobza, Gregory V. Steele

Publications of the US Geological Survey

Nitrate, age tracer, and continuous groundwater-level data were interpreted in conjunction with airborne electromagnetic (AEM) survey data to understand the movement of nitrate within the Bazile Groundwater Management Area (BGMA) in northeastern Nebraska. Previously published age tracer data and nitrate data indicated vertical stratification of groundwater quality. Younger groundwater sampled within shallow parts of the aquifer had higher concentrations of nitrate, with 70 percent exceeding the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter. In contrast, groundwater sampled from deeper parts of the aquifer indicated that nitrate concentrations were less than 2 milligrams per liter ...


Stratigraphy, Petrology, Diagenesis, Paleontology, And Depositional Environments Of The Harrisburg Member Of The Kaibab Formation In Northern Arizona And Southern Utah, Zachery T. Case 2020 Stephen F. Austin State University

Stratigraphy, Petrology, Diagenesis, Paleontology, And Depositional Environments Of The Harrisburg Member Of The Kaibab Formation In Northern Arizona And Southern Utah, Zachery T. Case

Electronic Theses and Dissertations

The Kaibab Formation has two members, the Fossil Mountain Member below and the Harrisburg Member above. They were deposited in shallow-marine shelf to restricted coastal settings. Stratigraphically above are the Rock Canyon Conglomerate and the Moenkopi Formation; consisting of the Timpoweap and Lower Red members; which are the only members present in the study area. The Rock Canyon Conglomerate was deposited in depressions and as a regolith. The Timpoweap and Lower Red members were deposited in shallow marine to tidal environments.

Nine stratigraphic units were identified in the Harrisburg Member. Units one, two, three, five, six, seven, and nine are ...


Delineating Of The Utica Shale/Point Pleasant Formation Play System To Determine Influence Of The Precambrian Basement In Northeastern Ohio, Jarrod R. Bridges 2020 Stephen F Austin State University

Delineating Of The Utica Shale/Point Pleasant Formation Play System To Determine Influence Of The Precambrian Basement In Northeastern Ohio, Jarrod R. Bridges

Electronic Theses and Dissertations

The Utica Shale/Point Pleasant Formation system has recently become a highly developed unconventional target for oil and natural gas production, leading to an increased desire for knowledge of the controls on deposition of this system. Precambrian basement features have long been known to affect deposition of older strata near these features across Ohio, but the effects of far field tectonics is not fully agreed upon. Precambrian faults and lineaments are known to exist and have been mapped, but are thought to have ceased their influence on deposition by the time of the Knox unconformity during the Cambrian. In the ...


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