Geomorphology Commons^™

The Art Of Landslides: How Stochastic Mass Wasting Shapes Topography And Influences Landscape Dynamics, Benjamin Campforts, Charles Shobe, Irina Overeem, Gregory Tucker

Faculty & Staff Scholarship

Bedrock landslides shape topography and mobilize large volumes of sediment. Yet, interactions between landslide-produced sediment and fluvial systems that together govern large-scale landscape evolution are not well understood. To explain morphological patterns observed in steep, landslide-prone terrain, we explicitly model stochastic landsliding and associated sediment dynamics. The model accounts for several common landscape features such as slope frequency distributions, which include values in excess of regional stability limits, quasi-planar hillslopes decorated with straight, closely spaced channel-like features, and accumulation of sediment in valley networks rather than on hillslopes. Stochastic landsliding strongly affects the magnitude and timing of sediment supply to …

Fossils On The Floor Mosaics In The Rotunda Of The Nebraska State Capitol Second Edition, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The idea for this project arose during a field trip to the Nebraska State Capitol led by my long-time friend and colleague, Joe Hannibal, of the Cleveland Museum of Natural History, during the Geological Society of America’s North-Central Section Meeting in Lincoln, Nebraska, on Saturday, April 26, 2014. One of Joe’s interests is historical buildings and their building stones. He put together a very useful guidebook to the building and its decorative stones (Hannibal, 2014) that we used on our tour.

One of the many places that we visited was the State Capitol Archives, located in the basement, where the …

Hydrodynamic Limitations To Mangrove Seedling Retention In Subtropical Estuaries, Kelly M. Kibler, Christian Pilato, Linda Walters, Melinda Donnelly, Jyotismita Taye

Flow-biota Interaction and Natural Infrastructure Design

Mangrove forest sustainability hinges upon propagule recruitment and seedling retention. This study evaluates biophysical limitations to mangrove seedling persistence by measuring anchoring force of two mangrove species (Rhizophora mangle and Avicennia germinans). Anchoring force was measured in 362 seedlings via lateral pull-tests administered in mangrove forests of two subtropical estuaries and in laboratory-based experiments. Removal mechanism varied with seedling age: newly-established seedlings failed due to root pull-out while seedlings older than 3 months failed by root breakage. Anchoring force of R. mangle seedlings was consistently and significantly greater than A. germinans (GLM: p = 0.002), however force to …

Land Use Effects On Fish Assemblages In Mississippi River Tributaries In Scott County, Ia And Rock Island County, Il, Benjamin Ford, Kevin Geedey

Urban Watershed Project

Fish assemblages are viable indicators of stream quality because they respond predictably to changes in abiotic and biotic factors, such as habitat and water quality, and human exploitation and species additions. In this a study we examined the relationship between fish abundance, diversity, and IBI (Index of Biotic Integrity), and urban and agricultural land use in Scott County, IA and Rock Island County, IL. Fish were sampled during the summer of 2021 within 12 local watersheds, which contain a variety of land use types. We followed a standardized sampling method of a single pass with a backpack electrofishing unit through …

Thickness Of Fluvial Deposits Records Climate Oscillations, Xiaoping Yuan, Laure Guerit, Jean Braun, Delphine Rouby, Charles Shobe

Faculty & Staff Scholarship

Fluvial deposits offer Earth’s best-preserved geomorphic record of past climate change over geological timescales. However, quantitatively extracting this information remains challenging in part due to the complexity of erosion, sediment transport and deposition processes and how each of them responds to climate. Furthermore, sedimentary basins have the potential to temporarily store sediments, and rivers subsequently rework those sediments. This may introduce time lags into sedimentary signals and obscure any direct correlation with climate forcing. Here, using a numerical model that combines all three processes—and a new analytical solution—we show that the thickness of fluvial deposits at the outlet of a …

New Hampshire Continental Shelf Geospatial Database: Surficial Geology Maps And Sediment Grain Size Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison

Data Catalog

The “New Hampshire Continental Shelf Geospatial Database: Surficial Geology Maps and Sediment Grain Size Data” consists of high-resolution surficial geology maps of the continental shelf off New Hampshire to Jeffreys Ledge in the Western Guff of Maine (WGOM) and supporting sediment grain size information. The surficial geology maps cover ~3,250 km² (Figure 1). The maps depict three different classifications based on the Coastal and Marine Ecological Classification Standards (CMECS; FGDC, 2012): Geoforms (major morphologic or physiographic features; Figure 2; Table 1), Geologic Substrate Subclass (Figure 3; Table 2), and Geologic Substrate Group (Figure 4; Table 2). The maps are …

Nebraska Statewide Groundwater-Level Monitoring Report 2021, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel

Conservation and Survey Division

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 in an effort to survey the state’s groundwater resources and to observe changes in its availability on a continuing 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, …

Landslide Detection In The Himalayas Using Machine Learning Algorithms And U-Net, Sansar Raj Meena, Lucas Pedrosa Soares, Carlos H. Grohmann, Cees Van Westen, Kushanav Bhuyan, Ramesh P. Singh, Mario Floris, Filippo Catani

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Event-based landslide inventories are essential sources to broaden our understanding of the causal relationship between triggering events and the occurring landslides. Moreover, detailed inventories are crucial for the succeeding phases of landslide risk studies like susceptibility and hazard assessment. The openly available inventories differ in the quality and completeness levels. Event-based landslide inventories are created based on manual interpretation, and there can be significant differences in the mapping preferences among interpreters. To address this issue, we used two different datasets to analyze the potential of U-Net and machine learning approaches for automated landslide detection in the Himalayas. Dataset-1 is composed …

Land-Surface Parameters For Spatial Predictive Mapping And Modeling, Aaron E. Maxwell, Charles Shobe

Faculty & Staff Scholarship

Land-surface parameters derived from digital land surface models (DLSMs) (for example, slope, surface curvature, topographic position, topographic roughness, aspect, heat load index, and topographic moisture index) can serve as key predictor variables in a wide variety of mapping and modeling tasks relating to geomorphic processes, landform delineation, ecological and habitat characterization, and geohazard, soil, wetland, and general thematic mapping and modeling. However, selecting features from the large number of potential derivatives that may be predictive for a specific feature or process can be complicated, and existing literature may offer contradictory or incomplete guidance. The availability of multiple data sources and …

Baseflow And Water Resilience Variability In Two Water Management Units In Southeastern Brazil, Lucas Vituri Santarosa, Didier Gastmans, Troy E. Gilmore, Jan Boll, Sebastian Balbin Betancur, Vitor Fidelis Monteiro Gonçalves

Conservation and Survey Division

Changes in climate and water demand in densely populated regions increasingly affect hydrological systems, and, in turn, impact socioeconomic conditions. In this case study, we identify how the hydrogeological frameworks of two water resource management units, Tietê-Jacaré (TJ) and Piracicaba-Capivari-Jundiaí (PCJ) in Sao Paulo state (Brazil), control the baseflow processes and resilience in the face of streamflow fluctuations in response to anthropogenic activities and climate variation. The results reveal between 40% and 75% contributions of baseflow to total streamflow in basins overlying crystalline and sedimentary aquifers. The basins in PCJ which mostly overly crystalline aquifers, have shorter water residence times …

Morphometric Quantification Of Cockpit Karst In A Jamaican Bauxite Mining Concession, M Sean Chenoweth

Research, Publications & Creative Work

A digital surface model (DSM) is used to characterize the landscape and topical karst landforms within a bauxite mining lease in north central Jamaica. Five case study sites are selected for detailed geomorphic analysis and cartographic visualization using a GIS. In Jamaica, tropical cockpit karst landscapes are composed of several landforms: cockpits, glades, corridors, saddles, and talus slopes. Evidence for the existence and quantification of these landforms is provided in this paper. Study sites have a mean basin area of 96,514 m2 , an average highest elevation of 541 m, mean lowest point of 444 m, with an average enclosed …

The Impact Of Sampling Methodology On Soil Bulk Density Measurement By The Clod Method, Aldi J. Airori, Trinity Baker, Judith Turk

Conservation and Survey Division

The clod method is a widely used and accurate bulk density method. However, its use is limited to sampling from soil pits. This study was conducted to: 1) determine whether clods collected from cores provide similar bulk density measurements to those collected from soil pits and 2) evaluate the impact of various clod bulk density methods on carbon stock calculation. Clods were collected from soil pits, 5.1 cm soil cores, and 8.9 cm soil cores. Three-dimensional laser scanning was used to measure the volume of the soil clods before and after oven-drying and bulk density was calculated as the dry …

Arcmap Hydrology Toolset: Wpes, How Do I...? Quick Guide, Bea E. Van Dam

Non-Thesis Student Work

This document provides guidance for performing hydrologic tasks using the Hydrology Toolset in ArcMap 10.x (ArcGIS Desktop). Covered here are an overview of the uses and limitations of the tools within the Hydrology Toolset, related tools from from additional ArcGIS toolsets, and step-by-step instructions for hydrologic workflows including digital elevation model (DEM) preparation, pit fill detection, "burning in" culverts for proper flow path routing, watershed and stream network delineation, and flow network statistics.

Application Of Chemostratigraphic Methods To Floodplain Alluvial Deposits Within The Big Harris Creek Basin, North Carolina, Samantha N. Sullivan, Jerry R. Miller, Carmen L. Huffman

Chemistry & Biochemistry Faculty Publications

Big Harris Creek, North Carolina, possesses a geomorphic history and alluvial stratigraphic record similar to many drainages in southern Appalachian Piedmont. An approximately 1 km reach of Upper Stick Elliott Creek, a tributary to Big Harris Creek, was used herein to (1) explore the use of chemostratigraphic methods to define and correlate late Holocene alluvial deposits along this relatively uncontaminated rural stream containing legacy sediments (historic, anthropogenically derived deposits), and (2) interpret depositional floodplain processes within small (<10 km²), headwater drainages. The lithofacies within four floodplain sections were described in channel banks and sampled at about 5 cm intervals. …

Total Station Field Surveying: Wpes, How Do I...? Quick Guide, Bea E. Van Dam

Non-Thesis Student Work

This document provides step-by-step guidance for performing surveys of field sites using a total station unit (TSU) and connected handheld data collector and for downloading collected point data. WPES uses a Sokkia CX-series TSU and a data collector running Carlson SurvCE software. Minor differences in instrument set-up may arise if using a different TSU. Major differences in data collection procedures will occur if using a different data collection software.

Strange Stones Of Skull Creek: Basalt Glacial Erratics And Omars In Eastern Nebraska, Robert M. Joeckel, Jesse T. Korus, Judith Turk, C. C. Arps, N. V. Arps, Leslie M. Howard

Conservation and Survey Division

We describe unusual stream- reworked glacially transported rocks (erratics) from a locality 50 km east of the limit of all pre- Illinoian (pre- 190 ka) Pleistocene glaciations in the central USA. Almost all these erratics consist of the igneous rock basalt, and of those, the vast majority have at least one fl at, smooth face. Some have two or more such faces that meet at obtuse angles along one or more well- defi ned, straight edges. We attribute these features, as well as laminations, plumose marks, and other features, to columnar jointing in ancient lava fl ows and shallow intrusions. …

2022 Nebraska Water Leaders Academy Final Report, Mark E. Burbach, Robert Matthew Joeckel, Brooke Mott, Gina S. Matkin

Conservation and Survey Division

Fifteen participants completed the 2022 Water Leaders Academy bringing the total number of graduates to 168 since the inception of the program in 2011. Assessments of participants’ transformational leadership skills, champion of innovation skills, water knowledge, engagement with water issues, civic capacity, entrepreneurial leadership behaviors, and boundary spanning skills increased significantly over the course of the year, according to both the participants and their raters. Feedback from the participants was highly positive and constructive. Academy planners are addressing participant concerns. Results of the program assessment indicate that the curriculum is meeting Academy objectives. Therefore, only minor changes are planned for …

Evidence For Metabolic Diversity In Meso-Neoproterozoic Stromatolites (Vazante Group, Brazil), Flavia Callefo, Fresia Ricardi-Branco, Mirian Mírian Liza Alves Forancelli Pacheco, Alexandre Ribeiro Cardoso, Nora Noffke, Verônica De Carvalho Teixeira, Itamar Tomio Neckel, Lara Maldanis, Emma Bullock, Dina Bower, Adalene Moreira Silva, Dario Ferreira Sanchez, Fabio Rodrigues, Douglas Galante

OES Faculty Publications

Deciphering the evolution of ecological interactions among the metabolic types during the early diversification of life on Earth is crucial for our understanding of the ancient biosphere. The stromatolites from the genus Conophyton cylindricus represent a datum for the Proterozoic (Meso to Neoproterozoic) on Earth. Their typical conical shape has been considered a result of a competition between microorganisms for space, light and nutrients. Well-preserved records of this genus from the "Paleontological Site of Cabeludo ", Vazante Group, São Francisco Craton (Southern Brazil) present in situ fossilized biofilms, containing preserved carbonaceous matter. Petrographic and geochemical analyses revealed an alternation between …

Silica Sinter And The Evolution Of Hot Springs In The Alvord/Pueblo Valleys, Southeast Oregon, Usa, Leslie Allen Mowbray, Michael L. Cummings

Geology Faculty Publications and Presentations

Hot springs in the Alvord/Pueblo valleys in southeastern Oregon are analogous to Basinand- Range hydrothermal systems where heat source and permeable pathways are met through crustal thinning. Silica sinter deposition at Mickey Springs, Alvord Valley, predates the late Pleistocene high stand of pluvial Lake Alvord. At Borax Lake, Pueblo Valley, sinter deposition occurred during the Holocene. This study examines the evolution of springs at Mickey Springs, where three morphologies of sinter are present: (1) basalt clasts surrounded by sinter in interbedded conglomerate and sandstone, (2) pool-edge and aprons of sinter surrounding depressions (12–32 m diameter), and (3) quaquaversal sinter mounds …

Recharge Assessment In The Context Of Expanding Agricultural Activity: Urucuia Aquifer System, Western State Of Bahia, Brazil, Glauco Z.S. Eger, Gerson C. Silva Junior, Eduardo A.G. Marques, Bernardo R.C. Leão, Diana G.T.B. Da Rocha, Troy E. Gilmore, Luís G.H. Do Amaral, Juremá A.O. Silva, Christopher Neale

Conservation and Survey Division

Groundwater recharge rate estimation is crucial to sustainable development of aquifers in intensely pumped regions, such as the Urucuia Aquifer System (UAS). A sedimentary aquifer in Western Bahia, Brazil, that underlies one of the major agricultural areas of the country where there has been major growth of irrigated areas. This study seeks to evaluate the recharge component of the water budget in the UAS area, based on three complementary techniques. The double-ring infiltrometer test was used to evaluate surface infiltration capacity, an important control on recharge. Water level data from wells (2011–2019 period, 19 wells) in the Brazilian Geological Survey’s …

Assessment Of The Impacts Of Urbanization On Land-Use And Land-Cover Changes Using Remote Sensing And Python At Gazipur District, Bangladesh, Atika Rahman Akji, Nowshin Ahsan Priyanka, Anwar Zahid, Muhammad Qumrul Hassan, Jowaher Raza, Nazrul I. Khandaker

Publications and Research

Urbanization has been the central demographic trend, not only in the Asia-Pacific region, but also for the entire world. Local geo-mapping is the vital tool for analyses of land-use and land-cover. This study attempts to classify land-use in unsupervised settings and create land-cover map by using open-source Landsat data integrated with GIS technologies and other ancillary resources. This work concentrates on Gazipur Sadar (an upazila or sub-district of the Gazipur District in central Bangladesh, part of the Dhaka Division) and Kaliakair, which are rapidly growing unplanned urban and industrial zones. The usage of python coding greatly assisted accomplishing the post-classification …

Determination Of Sustainable Zones For Groundwater Abstraction From The Multi-Layered Aquifer System In The Bengal Basin, Bangladesh, Anwar Zahid, Muhammad Qumrul Hassan, Nazrul I. Khandaker

Publications and Research

The use of deep groundwater (±300 m deep) is becoming an important issue in the Bengal Basin, due to both water quality problems and an acute shortage of available water in upper aquifers. In southeastern Bangladesh, multi-layered aquifer conditions exist with arsenic contamination at shallow depths, and high iron and brackish groundwater occurring mainly in the deeper layers. Many previous studies have offered explanations for the high concentrations of dissolved arsenic in groundwater - most of which proposed that the arsenic is derived from geo-genic sources and its release in groundwater is through natural processes, not the result of anthropogenic …

The Importance Of Monitoring To Assess The Impact Of Climate Change On Groundwater Resources In Bangladesh, Muhammad Qumrul Hassan, Anwar Zahid, Nazrul I. Khandaker

Publications and Research

Groundwater is the major source of fresh water across much of the world, but there has been very little study on the impacts of climate change on this precious and finite resource. Rising levels of greenhouse gases are likely to increase the global average surface temperature over the next 100 years, raise sea levels and reduce soil moisture. The amount of water stored in the soil is fundamentally important to agriculture and influences the rate of actual evaporation, groundwater recharge and runoff. Rising sea levels would cause the tidal saltwater wedge to intrude further upstream in rivers, with resulting changes …

Geology And Hydrogeology Of Northeastern Nebraska: Geology, Water Management And Geological Hazards, Nebraska Geological Society Field Trip 2021, Robert F. Diffendal Jr., Sue Olafsen Lackey, Douglas R. Hallum

Conservation and Survey Division

The 2021 Nebraska Geological Society field trip will provide an overview of the geology and hydrogeology of northeast Nebraska, the groundwater quality and quantity issues unique to the region, water management issues and decision-making, and ongoing work relating to water quality and geologic (hydrostratigraphic) framework, along the lower Niobrara and Missouri rivers Between Spencer Dam and Homer Nebraska. This program will be comprised of an auto tour with multiple stops on Saturday October 16 through Monday October 18 as illustrated in Map 1. The tour will begin with an examination of the Spencer Dam site and several locations in and …

Diatoms Of The Intertidal Environments Of Willapa Bay, Washington, Usa As A Sea-Level Indicator, Isabel Hong, Benjamin P. Horton, Andrea D. Hawkes, Robert J. O.Donnell Iii, Jason S. Padgett, Tina Dura, Simon E. Engelhart

Geological Sciences Faculty Scholarship

An understanding of the modern relationship between diatom species and elevation is a prerequisite for using fossil diatoms to reconstruct relative sea level (RSL). We described modern diatom distributions from seven transects covering unvegetated subtidal environments to forested uplands from four tidal wetland sites (Smith Creek, Bone River, Niawiakum River, and Naselle River) of Willapa Bay, Washington, USA. We compared our diatom dataset (320 species from 104 samples) to a series of environmental variables (elevation, grain-size, total organic carbon (TOC_SOM), and porewater salinity) using hierarchical clustering and ordination. While no single variable consistently explains variations in diatom assemblages …

Leveraging Natural Resources Toward Resilience: Outreach, Restoration, And Monitoring For A Resilient Nh Coast, Alyson Eberhardt, David M. Burdick, Gregg E. Moore

Faculty Publications

Both sound science and meaningful community engagement are critical to creating resilient coastlines given that important natural resources and high population densities coexist in these areas. Salt marshes and sand dunes provide important benefits to the people who live near them, such as mitigating flood impacts, when the condition of the ecosystem is robust enough to support such functions. To enhance the ability of these systems to perform ecosystem services, the goals of this project were to 1. Empower landowners to sustainably manage their own property to support coastal ecosystems and the benefits they provide, 2. Restore eroded sand dunes …

Ductile And Brittle Deformation Of Slackwater Deposits In The Tucannon River Valley, Chelsi K. Howard

Geosciences Student Work

The Tucannon River valley in eastern Washington is home to a number of ductile and brittle soft-sediment deformation. This project aims to look at ductile deformation by classifying and comparing styles of clastic dikes in the field and to look at brittle deformation by analyzing small faults in localized outcrops. Clastic dikes are sedimentary intrusions into other sedimentary strata. There are three main types of clastic dikes: injection, extrusion, and sugtrusion. In addition, two subcategories of clastic dikes are described as sheeted dikes and fault injection dikes. Ductile and brittle deformation occurs in “slackwater” deposits associated with margins of glacial …

Four Decades Of Understanding Martian Geomorphology: Revisiting Baker's "The Geomorphology Of Mars", Anshuman Bhardwaj, Lydia Sam, Saeideh Gharehchahi

Research, Publications & Creative Work

Owing to multiple successful orbiter and rover missions in the past two and half decades, our understanding of the Martian atmosphere, terrain, and subsurface has continuously evolved. This prompts the need to revisit the first holistic review of Martian geomorphology based on useful images from Viking Mission orbiters, authored by Prof. Victor R. Baker. Several of the remote sensing-based interpretations and recommendations in Baker’s (1981) paper are as valid even today as they were four decades back. With an unprecedented focus on Mars exploration in the coming decades, it is important to briefly revisit the advances and prospects in Martian …

Linking Human Activities To Water Quality In Coastal New England: Past And Present, Amelia Hurst

University Scholar Projects

This project examines the timing and effect of direct and indirect anthropogenic and natural influences on the marine environment in embayments in southern New England over the past decades to century timescale. We investigated the effects of human land use from colonial through post-industrial times, determined baseline conditions and natural climatic variability, and analyzed the response of marine ecosystems to specific local management actions aimed to improve water quality. A coastal sediment core was taken in Mumford Cove, CT and was analyzed downcore for eutrophication markers (C: N, %C, %N, d¹⁵N, d¹³C) and metals (Hg, Pb, …

Late Amazonian Wind Regimes And Landscape Evolution In Northern Meridiani Planum, Mars, Thomas Stritch

Geology: Student Scholarship & Creative Works

Aeolian process have dominated the lower latitudes of Mars for billions of years. Aeolian landforms can act as records of current and past climates and landscape evolution processes. The etched deposits of Meridiani Planum, a vast suite of layered bedrock extending from southwest Arabia Terra to Schiaparelli crater, have long been noted to have been eroded by aeolian processes. However, little detailed work on the aeolian landforms of Meridiani Planum beyond the Opportunity rover landing site has been done. In this study, I examine wind streaks, aeolian bedforms (including dunes and large ripples), and yardangs in a valley about 370 …