Geomorphology Commons^™

Sedimentary Dynamics In Tubular Sandstone Caves, Porto União, Southern Brazil, Leandro Bianchini, Julio Cesar Paisani

International Journal of Speleology

Clastic sedimentation in sandstone caves remains poorly understood, particularly in systems with tubular morphology. This study investigates sedimentation, reworking, and sediment removal dynamics in the Legru Cave system, southern Brazil, based on the integrated analysis of sedimentary facies, microstructures, and microfeatures, combined with optically stimulated luminescence dating. The results indicate that conduit infilling is dominated by high-density flows, including cohesive debris flows, partially diluted multiphase flows, and flows with intermediate rheological behavior between mud flow and hyperconcentrated flow, in addition to shallow flow alternations. Sediment supply is predominantly allochthonous, related to hillslope-derived material delivered by overland flow and mud flows, …

Nebraska Statewide Groundwater-Level Monitoring Report 2025, Aaron R. Young, Mark E. Burbach, Sue Olafsen Lackey, Robert Matthew Joeckel, Jeffrey Westrop

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

A Tale Of Two Microbialities: Stromatolites And Microbially Induced Sedimentary Structures, Nora Noffke, Stanley M. Awramik

OES Faculty Publications

Microbialites are biosedimentary structures built by microbial mats. Five microbialite groups are distinguished: stromatolites, thrombolites, dendrolites, leiloites and microbially induced sedimentary structures (MISS). This contribution discusses the two most abundant microbialite groups in marine settings, stromatolites and MISS. Microbial interactions with clastic sediment are very similar in both stromatolite and MISS formation. However, in stromatolites, syngenetic carbonate production caused by photoautotrophic and heterotrophic metabolisms and by calcimicrobes also takes place. More so, carbonate may precipitate within the extracellular polymeric substances. Due to the various carbonate forming processes as well as recrystallisation, the microscopic mat fabrics within stromatolite laminae are rarely …

Scanning Electron Microscopy As A Potential Tool For Distinguishing Charcoal From Dark, Oxidized, Biomass, João Vitor Dos Santos, Aleksandar I. Goranov, Lais Gomes Fregolente, Joao Marcos De Lima-Faria, Diego Stefani Teodoro Martinez, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Condensed aromatic carbon (ConAC) is widely used as a proxy for organic materials derived from biomass burning. However, recent evidence shows that ConAC can be also formed through nonpyrogenic oxidative processes. This study presents a proof-of-concept investigation using scanning electron microscopy (SEM) to distinguish charcoal from dark, ConAC-rich materials produced by ambient oxidation of biomass. Pine wood exposed to long-term iron-mediated oxidation was compared with unaltered wood and a controlled laboratory-generated charcoal reference. Conventional geochemical analytical methods, including benzenepoly(carboxylic acid) (BPCA) analysis, Fourier transform–ion cyclotron resonance–mass spectrometry (FT-ICR-MS), solid-state 13C nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis, confirmed substantial …

Last Glacial Maximum And Late Glacial Aeolian Sand Activity, South-Central Indiana, Usa, H. M. Loope, J. L. Antinao, P.R. Hanson, P. M. Jacobs, D. A. Grimley

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Investigating Netarts Bay, Oregon Coastal Landscape Change From Tectonic Subsidence Through Isotopic, Stratigraphic Records And Quantifying Dune Influence On Salt Marsh Morphodynamics, Emily Hall

Open Access Master's Theses

Coastal salt marshes on tectonically active margins face dual pressures from episodic seismic events and anthropogenic modifications. This study investigated how the 1700 CE Cascadia Subduction Zone earthquake and the 1900 CE introduction of invasive dune grass influenced back-barrier salt marsh morphodynamics at Netarts Bay, Oregon. It was hypothesized that (1) salt marsh habitats and elevation transitions would be detectable in geochemical proxies preserved in stratigraphy, (2) modern dune stabilization significantly limits mineral sediment delivery to the salt marsh, and (3) this reduction would be preserved in the stratigraphic record. Stratigraphic and isotopic analyses of sediment cores incorporating CT scans, …

Report 17—Revisions To The Articles Of Organization And Procedure Of The Commission On Stratigraphic Nomenclature Of The Americas, Lynn T. Dafoe, Robert B. Macnaughton, Marie-Perre Aubry, Carlton E. Brett, James R. Lehane, Fernando Núñez-Useche, Randall C. Orndorff, Frank Brunton, Lucy E. Edwards, Richard H. Fluegeman, Howard Harper, Robert Matthew Joeckel, Norman P. Lasca, B. H. Tew

Conservation and Survey Division: Faculty and Staff Publications

Several revisions to the Articles of Organization and Procedure for the North American Commission on Stratigraphic Nomenclature have been adopted following the 75th, 79th, and 80th annual meetings of the Commission in 2020, 2024 and 2025, respectively. Of these, the most substantial change was revision of Article III regarding membership composition of the Commission and the addition of new member organizations from Central and South America and the Caribbean region. As a result, the Commission also voted to change its name to be more inclusive of the expanding membership, with approval of the name: Commission on Stratigraphic Nomenclature of the …

Evidence Of Backwater Morphodynamics In Stratigraphy On Earth And Mars: Implications For Ancient Mars, Cory Mitchell Hughes

Graduate Theses and Dissertations

Geologic evidence indicates that liquid water once flowed in abundance across the martian surface. For this reason, in the search for evidence of extraterrestrial life, Mars represents a prime target for scientific inquiry. River systems encode climatic and environmental signals in their deposits on Earth and Mars, often in fan-shaped landforms (e.g., alluvial fans, river deltas, etc.). Distal fan-shaped deposits (i.e., river deltas), in particular, act as a relatively high-fidelity record of dynamic geologic processes. As such, NASA frequently sends rovers to locations on Mars’ surface with hypothesized river deltas (e.g., Perseverance and Jezero crater). Problematically, there are many different …

Mapping Sedimentary And Crustal Thicknesses In The Northern Atlantic Ocean From Public Domain Geophysical Data, Hermione Lofton

College of Arts and Sciences: Undergraduate Theses and Other Student Projects

The Northern Atlantic Ocean is a complex region that contains many inactive and active tectonic features. These features include the Jan Mayen Microcontinent, Jan Mayen Fracture Zone, Aegir Ridge, Kolbeinsey Ridge, the Greenland-Iceland-Faroe Ridge, the Voring Plateau, the Voring Spur, and the Iceland Hotspot. This project is motivated by the region’s complex geology and its highly debated tectonic history and disputed crustal affinity. This study aims to evaluate tectonic elements of the Northern Atlantic Ocean with three major objectives. The first objective is to develop a map of crustal thickness from publicly available seismic refraction data. For the second objective, …

Rishon Le-ẒIyyon, Winepress Park: Geomorphology And Sedimentology, Joel Roskin, Yotam Asscher

Qadum: Journal of Excavation Reports from Israel

An extensive brown sandy double-unit sediment, draping large parts of the archaeological remains at the Winepress Park in Rishon Le-Ẓiyyon, is suggested to be associated with the previously reported, undated ʻEn Ha-Qore clay. Based on relative age port-OSL profiling, the depositional mechanism of this unit and the overlying sand is suggested to be related to late Holocene, dune-dammed winter ponds. These aeolian-fluvial dune-damming processes may have been partly triggered by intensive Byzantine human activity that may have led to sand mobilization.

Groundwater In Nebraska, Troy E. Gilmore, Jesse T. Korus Dr.

Conservation and Survey Division: Faculty and Staff Publications

What is groundwater? Groundwater is water that fills and moves between spaces in underground rocks, gravel, sand, or other materials.

Usu Luminescence Lab Project 356: Durango Colorado Glacial And Fluvial Deposit Luminescence Age Results, Tammy M. Rittenour

Browse all Datasets

Luminescence dating of outwash terraces and glacial moraines. Project investigated the age of older (Bull Lake?) glacial advance sequences near Durango Colorado. Project was supervised by Dr. Jon Harvey at Fort Lewis College. Research was part of an undergraduate research project conducted by Josh Lingbloom.

Revealing Watery Geologies: Softening The Mississippi River Bluffs In Saint Paul, Minnesota, Chloe Kahn

Masters Theses

How is a place shaped by the geologies beneath it? In Saint Paul, Minnesota, the geologic ground tells the story of the different forces and processes that shaped it through time, but in the most recent geologic period of the anthropocene, industrialization and urban development have covered up these stories. On the edge of downtown, where the city meets the Mississippi River, an eighty foot concrete wall replaces the natural form of the bluff shaped by glacial and riverine activity. This thesis peels back the anthropogenic materials we encounter every day and explores Saint Paul through deep time– exploring how …

Latah Formation: History And Case Studies, Kylee M. Woodworth

2025 Symposium

The Latah Formation is a series of discontinuous sedimentary interbeds between the flows of the Columbia River Flood Basalts outcropping across northern Idaho and eastern Washington. Ages ranging between the Middle to Upper Miocene, the sediments represent varied fluvio-lacustrine environments. The deposits are predominantly composed of claystones and shales as alternating, laminated couplets, many containing a variety of fossils. Though the sediments may appear similar across localities, they come from different source rocks, ranging from ashes from Yellowstone hotspot to metamorphic rock from nearby hills. These ancient lacustrine and fluvial environments allowed for great preservation of fossils, often in great …

Older Groundwater Reservoirs In Nebraska, Marvin P. Carlson, Steven S. Sibray

Conservation and Survey Division: Faculty and Staff Publications

Sedimentary rocks below Nebraska's regional water table are saturated down to the crystalline igneous and metamorphic rocks of Precambrian age. The total thickness of these sedimentary rocks ranges from about 600 feet to over 10,000 feet. Nearly all current wells in Nebraska produce water from the near-surface, unconsolidated or partly consolidated rocks. Most studies to date -- interpretive reports, test drilling, inventory of wells, monitoring water levels, and water quality determinations -- have concentrated on these near-surface sources of groundwater.

Decadal To Millennial-Scale Morphodynamic Evolution Of Microtidal Marshes, Samuel Mason Zapp

LSU Doctoral Dissertations

Tidal marshes are susceptible to rapidly converting to open water due to their low elevations within the tidal frame. A continuous supply of externally supplied mineral sediment and in situ organic material production is necessary to offset elevation losses from relative sea level rise and erosion. Complex feedbacks between hydrodynamics, the erosion, transport, and deposition of sediment, and physical modification of the landscape by the establishment of intertidal vegetation govern the spatial and temporal patterns of elevation response. This dissertation focuses on modeling how these dynamics drive marsh landscape evolution in the past, present, and into the future under changing …

Landslide At River's Edge: Alum Bluff, Apalachicola River, Florida, Joann Mossa, Yin-Hsuen Chen

Center for Geospatial Science, Education & Analytics Faculty Publications

When rivers impinge on the steep bluffs of valley walls, dynamic changes stem from a combination of fluvial and mass wasting processes. This study identifies the geomorphic changes, drivers, and timing of a landslide adjacent to the Apalachicola River at Alum Bluff, the tallest natural geological exposure in Florida at similar to 40 m, comprising horizontal sediments of mixed lithology. We used hydrographic surveys from 1960 and 2010, two sets of LiDAR from 2007 and 2018, historical aerial, drone, and ground photography, and satellite imagery to interpret changes at this bluff and river bottom. Evidence of slope failure includes a …

Stratigraphy And Osl Chronology Of Lunette Deposits Indicates That Nebraska’S Rainwater Basins Formed By Aeolian Deflation Between 39 And 25 Ka, P.R. Hanson, Robert Matthew Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Early Holocene Interaction Of Aeolian, Alluvial, And Lacustrine Processes In A Dune-Dammed Valley In The Central Nebraska Sand Hills, Gpsia Mahoney, R. D. Mandel, P.R. Hanson, Sherilyn Fritz

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Using Simulated Cascadia Fakequakes To Interpret Paleotsunami Patterns, Anthony M. Joyce

All Master's Theses

This study uses GeoClaw to simulate 8 instantaneous rupture test earthquakes and 48 stochastic earthquakes (Fakequakes) along the Cascadia Subduction Zone to better understand tsunami generation and propagation. The primary goal is to evaluate how variations in Fakequake rupture patterns affect tsunami heights at coastal sites in the Pacific Northwest. The study focused on comparing inner and outer coast wave heights and impacts to understand how the Olympic Peninsula provides a barrier of protection to inner coast sites from southern-generated tsunamis, and implications for tsunami hazard at Naval Air Station Whidbey Island (NASWI).

Test earthquakes show increased amounts of slip …

Conservation And Survey Division 2024 Annual Report, R.M. Joeckel, Michele Waszgis

Conservation and Survey Division: Faculty and Staff Publications

The Conservation and Survey Division of the University of Nebraska - Lincoln is the agency designated by statute to investigate and interpret the geologically related natural resources of the State, to make available to the public the results of these investigations, and to assist in the development and conservation of these resources. It consists of program areas in geology, water, soils and remote sensing-geographic information systems.

Geomorphic Evolution Of St. Augustine Inlet, St. Johns County, Florida, Kristen Becker

Theses and Dissertations

Tidal inlets interrupt longshore sediment transport, influencing adjacent beach morphology and allowing the exchange of water and sediment between the open oceans and protected back barrier bay. Inlets evolve through a combination of natural processes and are highly dynamic zones where sediment exchanges cause shifting shoreline positions nearby and create new morphological features. Barrier islands/beaches that are close in proximity to inlets evolve and are an important natural feature that dissipates wave energy and protects inland areas. Both natural and anthropogenic processes that affect barrier islands will be investigated during this study, including storm activity, waves, wind, water level, and …

New Constraints On The Stratigraphic Architecture And Evolution Of Mississippi River Delta Lobe Activity: Barataria Basin, Southeastern La, Wilke Coleman

LSU New Orleans Theses and Dissertations

Barataria Basin is a shallow water, interdistributary estuary that has evolved in response to dynamic depositional regimes governed by distributary avulsion and reworking of sediments by coastal processes. In the Mississippi River delta plain, the migratory nature of the River has produced an evolving landscape constructed through episodes of regressive and transgressive sedimentation. These processes produce unique depositional signatures in the stratigraphic record, however the transgressive component of the delta cycle often results in obliteration of the regressive phase. This study uses a modern suite of geophysical and sediment core data to construct a revised geologic framework in Barataria Basin, …

Sedimentary Characteristics Of Flood Deposits In Coastal And Fluvial Environments: Examples From Washover Fans (North Carolina, Usa) And Floodplain Deposits (Mississippi, Usa), Shara Gremillion

Dissertations

Extreme flooding from severe and prolonged meteorological events and / or overbanking rivers are some of the most deadly and expensive disasters globally, impacting millions of lives, the environment, and property. People living in vulnerable areas, such as near coasts and rivers, are the first to be impacted with effects of these flood hazards. Scientific studies and their results can aid communities and officials in planning and preparing for those flood impacts. In this three-part study, flood impacts from coastal storms in North Carolina, and flooding along the Mississippi River (MSR) in the state of Mississippi, USA are assessed from …

Polygenetic Cave Sedimentation And Speleogenesis In The Mccloud Limestone Of Northern California, Niles Lathrop

Masters Theses & Specialist Projects

Caves in the Permian-aged, McCloud Limestone of the Klamath Mountains of Northern California preserve a diverse range of clastic sediments that represent broad-scale variations in paleo-hydrologic conditions and transport mechanisms that hint at varied modes of speleogenesis through local landscape development. Caves in the McCloud Limestone exhibit a range of cave passage geometries and arrangements that suggests periods of both hypogene and epigene cave development through temporal and spatial scales. This study evaluates the variability in the distribution, mineralogy, and transport mechanisms of clastic-cave sediments in seven hydrologically-distinct caves in the McCloud Limestone to establish relationships between clastic-cave sedimentation and …

Exploring Overbank Sediment Deposition Variation In Heavily Modified Floodplains Of The Lower Mississippi River: A Sedimentological And Geophysical Analysis, Seth Fradella

Master's Theses

Since the 1930s, the Lower Mississippi River (LMR) has experienced large-scale modifications to the channel profile and surrounding floodplains through dams, dikes, revetments, dredging, and channel cutoffs. Although these changes have improved navigation and reduced flood risk, unanticipated changes to the major flood return period, individual flood severity and duration, and sediment regime have become increasingly apparent and sometimes problematic, such as the 2011 and 2018-2020 floods. Flood control levees along the LMR have reduced the natural floodplain area by 70-90%, resulting in heavily restricted overbank storage capacity of water and sediment. For the same flood events in recent history, …

Theory Of An Automatic Seepage Meter And Ramifications For Applications, V. A. Zlotnik, D. K. Solomon, D. P. Genereux, T. E. Gilmore, C. E. Humphrey, A. R. Mittelstet, A. V. Zlotnik

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Lower Bound On Preserved Flood Duration In Fluvial Bedform Stratigraphy (Experimental Dataset), Robert C. Mahon, Vamsi Ganti, Madeline M. Kelley, Debsmita Das, Victoria Sanchez, Giancarlo Portocarrero, Mayson Fredricks

Lower Bound on Preserved Flood Duration in Fluvial Bedform Stratigraphy (experimental dataset)

This data is collected to assess the role of hydrograph timescale relative to dune migration on the preservation of cross sets in the stratigraphic record. The data presented here are of dune evolution under steady-state conditions, as well as three hydrographs of the same magnitude but varying timescales.

Methodology:

We collected data from four experiments tracking bedform evolution in a 22-m-long, 0.56-m-wide, 0.9-m-deep flume at the University of New Orleans Dynamics of Sedimentation laboratory. We conducted an equilibrium experiment (discharge value 0.027 m3/s) and three flood experiments, which were characterized by a symmetrical flood wave. In all flood experiments, the …

Stage And Discharge Prediction From Documentary Time-Lapse Imagery, Kenneth W. Chapman, Troy E. Gilmore, Mehrube Mehrubeoglu, Christian D. Chapman, Aaron R. Mittelstet, John E. Stranzl Jr.

Conservation and Survey Division: Faculty and Staff Publications

Imagery from fixed, ground-based cameras is rich in qualitative and quantitative information that can improve stream discharge monitoring. For instance, time-lapse imagery may be valuable for filling data gaps when sensors fail and/or during lapses in funding for monitoring programs. In this study, we used a large image archive (>40,000 images from 2012 to 2019) from a fixed, ground-based camera that is part of a documentary watershed imaging project (https://plattebasintimelapse.com/). Scalar image features were extracted from daylight images taken at one-hour intervals. The image features were fused with United States Geological Survey stage and discharge data as response variables …

Analysis Of Legacy Gravity Data Reveals Sediment-Filled Troughs Buried Under Flathead Valley, Montana, Usa, Ali Gebril, Mohamed A. Khalil, Robert Matthew Joeckel, James Rose

Conservation and Survey Division: Faculty and Staff Publications

Shallow, dominantly silt- and clay-filled erosional troughs in Quaternary sediments under the Flathead Valley (northwestern Montana, USA) are very likely to be hydraulic barriers limiting the horizontal flow of groundwater. Accurately mapping them is important because of increasing demand for groundwater.We used a legacy Bouguer gravity map measured in 1968. The directional derivatives of the map are computed, and the map was enhanced by implementing edge detection tools.We produced generalized derivative, maximum horizontal gradient, total gradient and tilt gradient maps through two-dimensional Fourier transform analysis. These maps were remarkably successful in locating buried troughs in the northern and northwestern parts …