Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Geology (1754)
- Hydrology (1268)
- Sedimentology (1227)
- Stratigraphy (1093)
- Paleontology (1044)
-
- Soil Science (1004)
- Environmental Sciences (253)
- Life Sciences (190)
- Geophysics and Seismology (168)
- Geochemistry (164)
- Tectonics and Structure (155)
- Ecology and Evolutionary Biology (154)
- Other Earth Sciences (144)
- Social and Behavioral Sciences (127)
- Paleobiology (123)
- Other Ecology and Evolutionary Biology (117)
- Entomology (114)
- Geography (107)
- Environmental Monitoring (85)
- Glaciology (83)
- Oceanography and Atmospheric Sciences and Meteorology (83)
- Natural Resources and Conservation (80)
- Physical and Environmental Geography (70)
- Engineering (64)
- Natural Resources Management and Policy (61)
- Environmental Indicators and Impact Assessment (58)
- Water Resource Management (52)
- Institution
-
- University of Nebraska - Lincoln (1214)
- University of South Florida (137)
- Central Washington University (102)
- University of Arkansas, Fayetteville (56)
- Portland State University (39)
-
- City University of New York (CUNY) (35)
- Louisiana State University (33)
- Western Kentucky University (33)
- Missouri State University (32)
- University of Kentucky (32)
- University of Southern Maine (29)
- LSU New Orleans (28)
- California Polytechnic State University, San Luis Obispo (21)
- Old Dominion University (20)
- The University of Southern Mississippi (20)
- Department of Primary Industries and Regional Development, Western Australia (19)
- University of New Mexico (18)
- West Virginia University (17)
- Western Michigan University (17)
- Utah State University (16)
- Western University (16)
- Stephen F. Austin State University (14)
- University of Dayton (14)
- Wilfrid Laurier University (14)
- University of Nevada, Las Vegas (13)
- Boise State University (11)
- Michigan Technological University (11)
- University of Montana (11)
- University of New Hampshire (10)
- Bucknell University (9)
- Keyword
-
- Nebraska (482)
- Geomorphology (127)
- Geology (110)
- Groundwater (103)
- Test (73)
-
- Hole (72)
- Logs (72)
- Water (69)
- Conservation and Survey Division (63)
- Map (61)
- Water Survey Paper (53)
- Resource (46)
- Wells (46)
- Irrigation (33)
- Groundwater Nebraska (31)
- Water Nebraska (31)
- Fluvial geomorphology (29)
- GIS (29)
- Level (29)
- Hydrology (27)
- Karst (27)
- Csd (26)
- News (26)
- Sediment transport (24)
- Soil (24)
- Sediment (22)
- Erosion (21)
- Remote sensing (21)
- Rivers (21)
- Decline (20)
- Publication Year
- Publication
-
- Conservation and Survey Division: Faculty and Staff Publications (897)
- Bulletin of the University of Nebraska State Museum (1924–2023) (112)
- International Journal of Speleology (97)
- Robert F. Diffendal, Jr., Publications (93)
- All Master's Theses (55)
-
- United States Geological Survey: Publications (54)
- All Faculty Scholarship for the College of the Sciences (41)
- Graduate Theses and Dissertations (41)
- Graduate Theses/Dissertations (32)
- Publications and Research (32)
- Maine Collection (28)
- LSU New Orleans Theses and Dissertations (27)
- Dissertations and Theses (26)
- Electronic Theses and Dissertations (21)
- Master's Theses (20)
- USF Tampa Graduate Theses and Dissertations (20)
- Department of Earth and Atmospheric Sciences: Faculty Publications (19)
- LSU Doctoral Dissertations (19)
- Theses and Dissertations--Earth and Environmental Sciences (17)
- School of Natural Resources: Faculty Publications (16)
- Earth and Planetary Sciences ETDs (15)
- Department of Earth, Environment and Sustainability Faculty Publications (14)
- Geography & Environment Publications (14)
- LSU Master's Theses (14)
- Masters Theses (14)
- Theses and Dissertations (14)
- Earth, Environmental, and Atmospheric Sciences Publications (12)
- Technical Bulletins (12)
- Theses and Dissertations (Comprehensive) (12)
- Journal of the Arkansas Academy of Science (11)
- Publication Type
Articles 151 - 180 of 2252
Full-Text Articles in Geomorphology
Nebraska Statewide Groundwater-Level Monitoring Report 2023, Aaron R. Young, Mark E. Burbach, Sue Olafsen Lackey, Robert Matthew Joeckel, Nawaraj Shrestha, Jeffrey Westrop
Nebraska Statewide Groundwater-Level Monitoring Report 2023, Aaron R. Young, Mark E. Burbach, Sue Olafsen Lackey, Robert Matthew Joeckel, Nawaraj Shrestha, Jeffrey Westrop
Conservation and Survey Division: Faculty and Staff Publications
This report is a synthesis of groundwater-level monitoring programs in Nebraska. It is a continuation of the series of annual reports and maps produced by the Conservation and Survey Division (CSD) of the University of Nebraska in cooperation with the U.S. Geological Survey (USGS) since the 1950s. Groundwater-level monitoring began in Nebraska in 1930 to survey the state’s groundwater resources and observe changes in its availability on a regular basis. The CSD and USGS cooperatively developed, maintained, and operated an observation-well network throughout the state. These two agencies were responsible for collecting and archiving this information, and for making it …
Transient Electromagnetic (Tem) Survey For Targeted Drilling On The Kurtzhals Property, Cedar County, Nebraska, Jesse Korus, Katherine (Katie) Cameron, Michele Waszgis
Transient Electromagnetic (Tem) Survey For Targeted Drilling On The Kurtzhals Property, Cedar County, Nebraska, Jesse Korus, Katherine (Katie) Cameron, Michele Waszgis
Conservation and Survey Division: Faculty and Staff Publications
The Kurtzhals property is in Section 19, Township 30N, Range 3 in Cedar County, Nebraska. The present land use is agricultural row crop, but past use included hog production. Two active irrigation wells are located on adjacent properties to the west and southwest. An irrigation well was installed in the northwest corner of the property in 2022. Due to the low yield (300 gallons per minute) of this well, Mr. Kurtzhals seeks to install an additional irrigation well to supplement the first. Several unsuccessful test holes had been drilled prior to the present survey. The purpose of this survey was …
Zircon Luminescence Dating Re-Visited, C. Schmidt, T. Halter, P.R. Hanson, A. Ulianov, B. Putlitz, G. E. King, S. Kreutzer
Zircon Luminescence Dating Re-Visited, C. Schmidt, T. Halter, P.R. Hanson, A. Ulianov, B. Putlitz, G. E. King, S. Kreutzer
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Age Dating Young Groundwater: How To Determine Groundwater Age From Environmental Tracer Data, D. K. Solomon, T. E. Gilmore
Age Dating Young Groundwater: How To Determine Groundwater Age From Environmental Tracer Data, D. K. Solomon, T. E. Gilmore
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Visualizing And Automating Past, Real-Time, And Forecast Dynamic Hazard Maps For Shallow Colluvial Landslides In Eastern Kentucky, Nathaniel O'Leary
Visualizing And Automating Past, Real-Time, And Forecast Dynamic Hazard Maps For Shallow Colluvial Landslides In Eastern Kentucky, Nathaniel O'Leary
Theses and Dissertations--Earth and Environmental Sciences
Landslide hazards are a persistent threat to communities and infrastructure in Eastern Kentucky, where steep slopes, shallow colluvial soils, and variable hydrological conditions make slope failures frequent. This thesis presents an integrated approach to landslide hazard mapping (LHM) through the development of dynamic, spatiotemporal LHMs for shallow colluvial landslides. Two studies within this work investigate and refine the use of the Lu and Godt (2008) factor of safety (FS) equation to improve landslide predictions. The first study establishes a novel LHM workflow using Hydrus-1D to simulate soil moisture infiltration and fluctuations from precipitation and evapotranspiration (ET) data. This study also …
High Resolution Sedimentary Investigations Of Extant Lakes In North America, John Dilworth
High Resolution Sedimentary Investigations Of Extant Lakes In North America, John Dilworth
Theses and Dissertations--Earth and Environmental Sciences
Investigation of past lake environments forms the discipline of paleolimnology. Paleolimnological studies seek to evaluate geophysical, geochemical, and ecological proxies and indicators contained within lake sediment archives. Using these potential stores of high-resolution environmental information, questions regarding climate, biological, and geochemical changes experienced by a lake and its watershed can be investigated. This dissertation research utilized lake sediment records from two lakes within North America to study different aspects of environmental change. This dissertation consists of three separate studies presented in three chapters.
Chapter Two presents a retrospective environmental assessment of Jackson Lake, Wyoming to investigate the impacts of dam …
Mining Contamination Of Legacy Deposits On Floodplains Along Turkey Creek, Western Border Of The Ozark Highlands, Hannah Riley Eades
Mining Contamination Of Legacy Deposits On Floodplains Along Turkey Creek, Western Border Of The Ozark Highlands, Hannah Riley Eades
Graduate Theses/Dissertations
Historical mining activities in the Tri State mining district in Southwest Missouri from 1850 to 1950 resulted in widespread metal contamination of stream sediments. Beginning in the 1840s, land disturbances associated with Euro-American settlement and agricultural expansion increased runoff and soil erosion rates resulting in the deposition of contaminated alluvium or legacy sediment on floodplains. This study assesses zinc (Zn) and lead (Pb) contaminated legacy deposits in cut-bank exposures along floodplains in Turkey Creek Watershed (119 km²) which drained mining areas in Missouri. Ore production histories were used date metal contamination profiles and calculate floodplain deposition rates in legacy deposits. …
Evaluating Field Evidence Of Fine-Grained Sediment Abrasion In Gravel-Bedded Rivers: A Case Study Of The Lillooet And Suiattle Rivers In The Cascade Volcanic Arc (British Columbia, Canada, And Washington, Usa), Devin T. Johnson
Honors Theses
Steep, gravel-bedded rivers are important sites for studying gravel abrasion, where material transported as bed load experiences size reduction and rounding due to grain-to-grain collisions. Studying fine sediment (diameter) abrasion and grain shape changes in fluvial systems is more challenging due to difficulties in quantifying sediment shape at this scale, but it is assumed that fine particles traveling in suspension do not experience abrasion. Improvements in particle characterization technology now allow for the accurate, rapid quantification of particle shape for sediments as fine as 0.8 μm through dynamic image analysis. Here we use the Camsizer X2 (CX2) to test the …
A Comparison Of Sediment Accumulation Effectiveness Behind Beaver Dam Analogues, One Rock Dams, And Post-Assisted Log Structures On East Foster Creek, Douglas County, Wa, Griffin Hansen
All Master's Theses
Waterways are valuable resources for communities and habitats, but are subject to degradation in the form of incision. This is a type of streambed erosion where streams narrow and deepen. Sediment control dams were placed on East Foster Creek in Douglas County, WA to control incision following the 2020 Pearl Hill fire. This study examined sediment capture in the ponds behind these dams, which included beaver dam analogues (BDAs), one rock dams (ORDs), and post-assisted log structures (PALS). Sediment capture may be influenced by several factors, including dam type, height, width, distance between dams, vegetation, land use, topography, soil type, …
The Effects Of Environmental Factors On Tsunami Propagation And Inundation: A Comparison Of Earth With Other Planetary Bodies, Austin Halstead
The Effects Of Environmental Factors On Tsunami Propagation And Inundation: A Comparison Of Earth With Other Planetary Bodies, Austin Halstead
All Master's Theses
Tsunamis are a universal hazard in any environment with oceans or lakes. Having a firm understanding of them is essential because of this. However, the vast number of tsunami studies have been solely on Earth, despite the growing evidence of oceans and lakes being on, or having once existed on, other planets and moons. In this study, I investigated tsunami behavior in non-Earth environments by testing the effects of varying viscosity and gravity. I conducted simulations using GeoClaw, Flow3D®, and VolcFlow on established tsunami benchmarks to identify consistent patterns in tsunami flow patterns and inundation. The results show …
Beach Erosion And Recovery Since Hurricane Ivan In 2004 Along A Headland-Bay Coast In Treasure Beach, Jamaica, Elandé Engelbrecht
Beach Erosion And Recovery Since Hurricane Ivan In 2004 Along A Headland-Bay Coast In Treasure Beach, Jamaica, Elandé Engelbrecht
Graduate Theses/Dissertations
Anthropogenic climate change is causing sea-level rise and shoreline changes that threaten the environment and economy of coastal communities in Caribbean Island nations. To assess this risk, this study quantifies shoreline changes at Treasure Beach in St. Elizabeth Parish on the south coast of Jamaica from 2001 to 2023. The effects of storm events on erosion were also assessed. Over 10 km of shoreline are assessed with about half being sandy pocket beaches ranging from 300 to 900 m in length, separated by rocky headlands and beach rock outcrops. Sand beach erosion trends since 2001 are assessed for seven sandy …
The Effect Of Seasonal Ice Cover Duration On Shoreline Erosion In Lake Michigan, Ryan S. Navarre
The Effect Of Seasonal Ice Cover Duration On Shoreline Erosion In Lake Michigan, Ryan S. Navarre
Dissertations, Master's Theses and Master's Reports
Shoreline erosion in Lake Michigan has been a significant concern for coastal management. Promoting coastal stability and resilience is paramount to protecting these environments, especially amid climate change. While several factors are key in understanding shoreline erosion, seasonal ice cover duration is a prominent yet understudied factor in the Great Lakes region. Here, the relationship between ice cover duration and shoreline erosion rates is assessed across 7 regions of Lake Michigan. An ice cover duration dataset was created for Lake Michigan for 2011 – 2020 and its shorelines were digitized for years with available high-resolution aerial imagery. The statistical relationship …
Hydrogeomorphic Response To Flooding In Northern Yellowstone National Park, Zachary P. Deluca
Hydrogeomorphic Response To Flooding In Northern Yellowstone National Park, Zachary P. Deluca
Graduate Student Theses, Dissertations, & Professional Papers
Understanding and predicting flood-induced geomorphic change, and the relative influences of fluvial forces and valley-bottom geometry on system response, are persistent quandaries in geomorphic process studies. We combine field surveys, remote sensing, and hydraulic modeling to assess the hydrogeomorphic effects of historic flooding in northern Yellowstone National Park (YNP) in a variety of channel configurations. We compare impulse, a metric that incorporates a flow duration threshold based on threshold channel theory, grain size, channel-bed slope, and flood depth and stream power estimates with hydrogeomorphic response. Measurements of pre- and post-flood active-channel width change in aerial photos captured geomorphic response associated …
Multiscale Characterization Of Splays Produced By A Historic, Rain-On-Snow Flood On A Large Braided Stream (Platte River, Central Usa), J. T. Korus, R. M. Joeckel, A. R. Mittelstet, N. Shrestha
Multiscale Characterization Of Splays Produced By A Historic, Rain-On-Snow Flood On A Large Braided Stream (Platte River, Central Usa), J. T. Korus, R. M. Joeckel, A. R. Mittelstet, N. Shrestha
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Locating And Assessing Oregon Trail Ruts With Aerial Stereophotographs, Satellite Imagery And Lidar, P.R. Hanson, Robert Matthew Joeckel, L. M. Howard
Locating And Assessing Oregon Trail Ruts With Aerial Stereophotographs, Satellite Imagery And Lidar, P.R. Hanson, Robert Matthew Joeckel, L. M. Howard
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Landscape And Paleoenvironmental Change In Stream Valleys Of The Central Great Plains, North America During Marine Isotope Stage 3 (Ca. 59-27 Ka)., T. Layzell, K. Andrzejewski, R. D. Mandel, P.R. Hanson
Landscape And Paleoenvironmental Change In Stream Valleys Of The Central Great Plains, North America During Marine Isotope Stage 3 (Ca. 59-27 Ka)., T. Layzell, K. Andrzejewski, R. D. Mandel, P.R. Hanson
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Integrated Geochronological And Chemostratigraphic Study Of Middle Miocene Strata (Ogallala Group) At The Eastern Margin Of The North American Great Plains, J. J. Smith, Robert Matthew Joeckel, H. L. Field, G. A. Ludvigson, A. Moller, A. Layzell, S. T. Tucker
Integrated Geochronological And Chemostratigraphic Study Of Middle Miocene Strata (Ogallala Group) At The Eastern Margin Of The North American Great Plains, J. J. Smith, Robert Matthew Joeckel, H. L. Field, G. A. Ludvigson, A. Moller, A. Layzell, S. T. Tucker
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Wetlands In The Nebraska Sandhills, Nawaraj Shrestha
Wetlands In The Nebraska Sandhills, Nawaraj Shrestha
Conservation and Survey Division: Faculty and Staff Publications
Infographic titled “Status of Wetlands in the Nebraska Sandhills” showing multiple maps and charts. The top left features a color-coded wetland persistence map where blue indicates more consistent wetlands and red indicates intermittent wetlands. Additional inset maps show a regional zoom and a U.S. location map highlighting Nebraska. A large scatter plot displays wetland occurrence percentages over time using MODIS (green points) and Sentinel (blue points) satellite data from 2000 to 2024. Text explains how wetlands vary seasonally and annually and how satellite imagery tracks these changes. A smaller bottom chart shows long-term wetland trends, noting increasing occurrence since 1984. …
Geology Of The Bishop 7.5-Minute Quadrangle And Geophysical Modeling To Constrain Syndepositional Deformation Of The Black Warrior Foreland Basin, Joseph Edward Lane
Geology Of The Bishop 7.5-Minute Quadrangle And Geophysical Modeling To Constrain Syndepositional Deformation Of The Black Warrior Foreland Basin, Joseph Edward Lane
Graduate Theses/Dissertations
The Black Warrior basin is a foreland basin formed by the Ouachita–Appalachian orogeny during the late Paleozoic Era. Mississippian strata record the transition from the carbonate platform within the Tuscumbia Limestone to the clastic-rich units within the overlying Pride Mountain Formation and Hartselle Sandstone. The western and southern-most fringes of the Black Warrior basin are covered by thin, post orogenic Cretaceous sediments of the East Gulf Coastal Plain. Geological mapping of the Bishop 7.5-Minute quadrangle revealed subtle deformation in Mississippian strata in the form of gentle folds (
Bank Erosion Dynamics In Response To Anthropogenic Disturbances In The Cuivre River Watershed Of Missouri, Usa, Nathan Douglas Sines
Bank Erosion Dynamics In Response To Anthropogenic Disturbances In The Cuivre River Watershed Of Missouri, Usa, Nathan Douglas Sines
Graduate Theses/Dissertations
Riverbank erosion is increasingly recognized as a pressing issue exacerbated by human activities. The Cuivre River, a tributary of the Mississippi River, located in northeast Missouri, has limited documentation on bank erosion, with the most recent study conducted in the early 1990s. This research aims to fill this gap by exploring the stream bank erosion dynamics from 1816 to 2015. The objectives are to: (i) understand the channel width dynamics for 1816 to 1994 ii) determine the sediment erosion and deposition volume along the riverbank in the period of 1994 to 2015. iii) identify the anthropogenic disturbances particularly land use …
Hydrogeomorphic Response Of Fluvial Systems To Climate Change - An Example From James River, Missouri, Afrida Aranya
Hydrogeomorphic Response Of Fluvial Systems To Climate Change - An Example From James River, Missouri, Afrida Aranya
Graduate Theses/Dissertations
Climate change has led to unpredictable hydrological patterns, significantly altering the fluvial environment and their flow regime. Despite extensive research, our knowledge about the impacts of climate change on flow regimes in the US Midwest is limited, particularly in karst-dominated fluvial landscapes. This research addresses this gap by investigating the effects of climatic change on the hydrogeomorphology of the James River, located in the karst-dominated Ozark Highlands in southwest Missouri, USA. The study focuses on two ~1.5 km stream segments—one relatively active and one stable in the context of geomorphology—near Springfield, Missouri. The research aims to (i) understand the changing …
Temporal And Spatial Connectivity And The Impacts Of Hydropower In The Magdalena River Basin, Colombia, Serena Lynn Butler
Temporal And Spatial Connectivity And The Impacts Of Hydropower In The Magdalena River Basin, Colombia, Serena Lynn Butler
Graduate Student Theses, Dissertations, & Professional Papers
Tropical regions hold untapped hydropower potential, but dam construction often adversely impacts multiple dimensions of connectivity in river systems, rigorous evaluation of which is often lacking. This study investigates temporal and spatial dimensions of longitudinal and lateral connectivity in the Magdalena River Basin, Colombia, a region with ongoing and planned hydropower projects. Limited in-situ monitoring data is a common challenge in tropical rivers. To address this, we utilized satellite imagery from Landsat (via Google Earth Engine) and Surface Water and Ocean Topography (SWOT) data. We examined alterations in the flow regime over time and relative to dam construction. We also …
(Non-) Recovery Of An Agricultural Stream From Straightening And Dredging, Aras Anderson Mann
(Non-) Recovery Of An Agricultural Stream From Straightening And Dredging, Aras Anderson Mann
Graduate Theses, Dissertations, and Problem Reports (ETD)
In recent history, natural, meandering streams have been straightened and dredged to reduce flooding. While this practice can be effective in reducing flooding locally, it often results in the degradation of stream water quality and aquatic ecosystems. A straighter channel inherently increases the stream gradient, which could increase flow velocity, shear stress, and potentially downstream sediment yield. Studies have shown that straightened, channelized streams often begin to return to a meandering pattern 35-50 years post-channelization. Yet cross-sectional surveys and air photo analysis of the stream reach in this study, Deckers Creek, indicate little to no observable trend of the stream …
10be Dating Of Last Glacial Maximum Moraines And Subsequent Glacial Retreat In Chirripó National Park, Costa Rica, Caleb Emeka Okpala
10be Dating Of Last Glacial Maximum Moraines And Subsequent Glacial Retreat In Chirripó National Park, Costa Rica, Caleb Emeka Okpala
Dartmouth College Master’s Theses
During the Last Glacial Maximum (LGM; ~26-19 ka) and Termination 1 (~19-12 ka), the expansion and retreat of glaciers across the Southern and Northern Hemispheres, as well as other paleoclimate proxies, document a complex pattern of global climate change. While the timing and magnitude of LGM cooling and subsequent warming is relatively well constrained in mid- and high-latitude regions across both hemispheres, less information is available about climate changes in the tropics. To provide more information about tropical climate conditions during the LGM and Termination 1, I mapped and dated the extents of past glaciers in two valleys in Chirripó …
River Response To Removal Of A Small Dam And Replacement With A Roughened Channel, Chandler Sabin
River Response To Removal Of A Small Dam And Replacement With A Roughened Channel, Chandler Sabin
All Master's Theses
Relatively few studies have analyzed how the removal of small dams and re-engineering of the channel affect river channel processes. The low-head Nelson Dam was built in 1920 on the Naches River in central Washington, causing two miles of aggraded sediments. This resulted in upstream flooding and excessive downstream incision that led to ineffective irrigation diversions, and hindered fish spawning. Nelson Dam was removed in 2021 and replaced with a graded, roughened, nature-like channel and a newly engineered diversion that was completed in 2023. The research presented here quantifies the effects of the Nelson Dam removal and channel redesign on …
Contribution Of High Turbidity To Tidal Dynamics In A Curved Channel In Zhoushan Islands, China, Li Li, Fangzhou Shen, Zhiguo He, Gangfeng Ma, Jiachen Wang, Kailong Huangfu
Contribution Of High Turbidity To Tidal Dynamics In A Curved Channel In Zhoushan Islands, China, Li Li, Fangzhou Shen, Zhiguo He, Gangfeng Ma, Jiachen Wang, Kailong Huangfu
Civil & Environmental Engineering Faculty Publications
The curved tidal channel, Luotou Deep-water Navigational Channel, is the main channel of the Ningbo Zhoushan Port, which is ranked first in the world. Tidal dynamics in the channel are spatially and temporally asymmetric. In this study, the three-dimensional tidal dynamics in the channel were analyzed using field data and simulated using FVCOM. The results show that the tides in the channel flood/ebb along the northern/southern bank near the bottom/surface layer and these asymmetries are due to the imbalanced Coriolis force, centrifugal force, sea-level gradient, and density gradient. Residual current velocity peaks (0.7 m/s) in the middle of the channel …
Quantifying Chemical Erosion In The Lithologically-Heterogenous Appalachian Valley And Ridge, Amelia Jayne Zanoni
Quantifying Chemical Erosion In The Lithologically-Heterogenous Appalachian Valley And Ridge, Amelia Jayne Zanoni
Graduate Theses, Dissertations, and Problem Reports (ETD)
Quantifying chemical erosion in the lithologically-heterogenous Appalachian Valley and Ridge
Amelia J. Zanoni
The interplay between physical and chemical erosion is well understood in landscapes underlain by a uniform rock type, but many regions are underlain by a mixture of rock types with varying erosion resistance and solubility. We used measurements of stream-water chemistry to estimate chemical erosion rates in the Appalachian Valley and Ridge, a region where the mechanisms of lithologic control over topography are poorly understood. Newly acquired stream water samples were collected from 51 locations across the research area during the Fall of 2023. The sampled waters …
Reverse Pseudo-Gours: A New Sub-Type Of Folia Observed In The Nerja Cave (Se Spain), Cristina Liñán Baena, Concepción Jiménez De Cisneros, Yolanda Del Rosal, Paolo Forti
Reverse Pseudo-Gours: A New Sub-Type Of Folia Observed In The Nerja Cave (Se Spain), Cristina Liñán Baena, Concepción Jiménez De Cisneros, Yolanda Del Rosal, Paolo Forti
International Journal of Speleology
A new sub-type of folia named “reverse pseudo-gour” has been observed and described in the Nerja Cave, southern Spain. It consists of fairly vertical, thin barriers (about 5 mm high and 2 mm thick) that develop on the underside of a sub-horizontal surface (shelfstone) and grow in the opposite direction to normal gours (rimstone dams), generating sinuous shapes. Their mineral composition is essentially calcium carbonate, although globular aggregates composed of clay and phosphate minerals have also been identified. The genesis and evolution of these reverse pseudo-gours occur just at the air-water interface and are controlled by (1) the sub-horizontality of …
Comparative Lineament And Geomorphic Analysis Of Chaotic Terrains And Noctis Labyrinthus, Mars, Sarah A. Walton
Comparative Lineament And Geomorphic Analysis Of Chaotic Terrains And Noctis Labyrinthus, Mars, Sarah A. Walton
Electronic Theses and Dissertations
Noctis Labyrinthus (NL) is an extensional trough network connecting the Tharsis rise and Valles Marineris on Mars. Chaotic terrains are a group of polygonally-fractured surface features commonly associated with subsidence due to rapid fluid loss within the subsurface. Polygonal surface patterns are seen at both sites, where geometric topographic highs are bounded by low troughs. Lineaments, topography, and geomorphology of NL and chaotic terrains were analyzed to determine tectonics and fluid influence in the formation and evolution of both sites. NL shows preferential fracture patterns associated with regional extension. Lineaments within chaotic terrains do not show cumulative preferential trends but …
The Broadwater Formation (Pliocene) Of Nebraska And Southeastern Wyoming, Robert F. Diffendal Jr., James B. Swinehart
The Broadwater Formation (Pliocene) Of Nebraska And Southeastern Wyoming, Robert F. Diffendal Jr., James B. Swinehart
Robert F. Diffendal, Jr., Publications
The Broadwater Formation, initially defined in 1945, is a Pliocene-aged coarse-grained alluvial deposit in Nebraska and southeastern Wyoming. It is characterized by a complex stratigraphic history and debated geologic interpretations. The formation is a rich resource of groundwater for the citizens of Nebraska and the Central Great Plains. We aim to synthesize and redefine the Broadwater Formation, shedding light on its distribution, geological characteristics, and paleoenvironmental significance. While historical hypotheses on Broadwater Formation paleovalley trajectories suggested northwest-southeast trending valleys, later investigations proposed wind-driven erosional patterns to explain the unique topographic features observed. The Broadwater is divided into an unnamed Upper …