Geomorphology Commons^™

Comparison Of Flow Dynamics And Bifurcation Angles In Tributary And Distributary Channel Networks, Thomas Coffey

Graduate Theses and Dissertations

The dynamics of channel mouth bifurcations on river deltas can be understood using theory developed in tributary channel networks. Bifurcations in groundwater-fed tributary networks have been shown to evolve dependent on diffusive ground water flow patterns

directly adjacent to the channel network, producing a critical angle of 72°. We test the hypothesis that bifurcation angles in distributary channel networks are likewise dictated by a diffusive external flow field, in this case the shallow surface water surrounding the subaqueous portion of distributary channels in a deltaic setting. We measured 25 unique distributary bifurcations in an experimental delta and 197 bifurcations in …

Timing Of Speleogenesis Of Las Karmidas Cave (Mexico): First Description Of Pseudokarst Developed In Ignimbrite, María Del Pilar Aliaga-Campuzano, Rafael López-Martínez, Pablo Dávila-Harris, Ramón Espinasa-Pereña, Adriana Espino Del Castillo, J.P. Bernal

International Journal of Speleology

Las Karmidas Cave (Puebla State, Mexico) is an unusual type of pseudokarstic cavity generated by piping and erosive processes within the contact of a diamicton and an overlying Quaternary ignimbrite. Morphological evidence suggests that the cave was developed in two stages: a phreatic stage and a vadose stage. The latter was characterized by the formation of carbonate speleothems. The absolute upper-age limit for the cave (168 +7.1/-7.5 ka) was established by U-Th dating of zircons grains extracted from the overlying ignimbrite, whilst a minimum age for the transition from a phreatic to vadose regime (95.6 ± 2.1 ka) was constrained …

Developing A Tree-Ring Chronology For Reconstructing Past Climate Conditions: Coral Pink Sand Dunes, Ut, Amy L. Cutter

McNair Scholars Research Journal

The Coral Pink Sand Dunes (CPSD) is one of the largest active dune fields in the Grand Staircase of the Colorado Plateau. A disjunct stand of ponderosa pine (Pinus ponderosa) seemingly thrives within the dune field. The presence of a multiple-aged stand suggests the site has experienced varied climatic conditions since becoming established. Other geomorphic systems in the region (e.g., arroyos) indicate sensitivity to small climate fluctuations; perhaps the dunes are similarly sensitive, leading to the question—could the trees be used to reconstruct past climate, and could that reconstruction be used to model dune activity with climate variability. The climate-growth …

A Numerical Model Investigation Of The Role Of The Glacier Bed In Regulating Grounding Line Retreat Of Thwaites Glacier, West Antarctica, Michael Scott Waibel

Dissertations and Theses

I examine how two different realizations of bed morphology affect Thwaites Glacier response to ocean warming through the initiation of marine ice sheet instability and associated grounding line retreat. A state of the art numerical ice sheet model is used for this purpose. The bed configurations used are the 1-km resolution interpolated BEDMAP2 bed and a higher-resolution conditional simulation produced by John Goff at the University of Texas using the same underlying data. The model is forced using a slow ramp approach, where melt of ice on the floating side of the grounding line is increased over time, which gently …

Results Of Test-Hole Drilling For Observation Well Planning In The Upper Loup Natural Resources District, Fall 2016, Douglas Hallum, Sue Olafsen Lackey

Conservation and Survey Division: Faculty and Staff Publications

The High Plains Aquifer underlies much of Nebraska (Figure 1). It is the primary source of groundwater within the Upper Loup Natural Resources District (ULNRD) of central Nebraska (Figure 2). Water derived from the aquifer is an important natural resource for the area and supplies water for recreation, wildlife and agriculture, as well as domestic, municipal, and industrial uses. A general lack of water level observations in the region (Figure 3), recently developed groundwater irrigated acres along the upper Calamus River (Figure 4), falling spring water levels measured in existing irrigation wells (Figure 5), and a stable to falling stream …

Evaporite Karst In Italy: A Review, Jo De Waele, Leonardo Piccini, Andrea Columbu, Giuliana Madonia, Marco Vattano, Chiara Calligaris, Ilenia D’Angeli, Mario Parise, Mauro Chiesi, Michele Sivelli, Bartolomeo Vigna, Luca Zini, Veronica Chiarini, Francesco Sauro, Russell Drysdale, Paolo Forti

International Journal of Speleology

Although outcropping rarely in Italy, evaporite (gypsum and anhydrite) karst has been described in detail since the early 20^th century. Gypsum caves are now known from almost all Italian regions, but are mainly localised along the northern border of the Apennine chain (Emilia Romagna and Marche), Calabria, and Sicily, where the major outcrops occur. Recently, important caves have also been discovered in the underground gypsum mines in Piedmont. During the late 80s and 90s several multidisciplinary studies were carried out in many gypsum areas, resulting in a comprehensive overview, promoting further research in these special karst regions. More recent …

Application Of Numerical Modeling To Study River Dynamics: Hydro-Geomorphological Evolution Due To Extreme Events In The Sandy River, Oregon, Sarkawt Hamarahim Muhammad

Dissertations and Theses

The Sandy River (OR) is a coastal tributary of the Columbia River and has a steep hydroshed 1316 square kilometers which is located on the western side of Mount Hood (elevation range 3 m to 1800 m). The system exhibits highly variable flow: Its average discharge is ~40 m³/s, and the highest recorded discharge was 1739 m³/s in 1964. In this study I model the geomorphic sensitivity of an 1800m reach located the downstream of the former Marmot Dam, which was removed in 2007. The hydro-geomorphic response to major flood has implications for system management and …

The Dynamic Geomorphic Setting Of The Late Pleistocene Hartley Mammoth Site: Burial And Skeletal Preservation In A Slump-Block Depression Near Abiquiu, New Mexico, Jennifer K. Muus

Earth and Planetary Sciences ETDs

Near Abiquiu in northern New Mexico, the skeletal remains of two mammoths were discovered in the summer of 2014 in the near-surface deposits of a very small alluvial channel. The channel occupies a depression on the backtilted top of a Toreva slump block, a highly unusual setting for a mammoth burial. Geomorphological investigation of the site has provided insight into processes leading to burial and preservation of the remains, as well as local environmental change. Field mapping of sediment sources and LiDAR scans of the contributing slope basin and slump bench provided a map of geomorphic features and surficial geologic …

Unusual Geologic Evidence Of Coeval Seismic Shaking And Tsunamis Shows Variability In Earthquake Size And Recurrence In The Area Of The Giant 1960 Chile Earthquake, M. Cisternas, E. Garrett, R. Wesson, T. Dura, Lisa L. Ely

All Faculty Scholarship for the College of the Sciences

An uncommon coastal sedimentary record combines evidence for seismic shaking and coincident tsunami inundation since AD 1000 in the region of the largest earthquake recorded instrumentally: the giant 1960 southern Chile earthquake (Mw 9.5). The record reveals significant variability in the size and recurrence of megathrust earthquakes and ensuing tsunamis along this part of the Nazca-South American plate boundary. A 500-m long coastal outcrop on Isla Chiloé, midway along the 1960 rupture, provides continuous exposure of soil horizons buried locally by debris-flow diamicts and extensively by tsunami sand sheets. The diamicts flattened plants that yield geologically precise ages to correlate …

The Tuscaloosa Marine Shale: Geologic History, Depositional Analysis, And Exploration Potential, Jessica D. Pair

Electronic Theses and Dissertations

The Tuscaloosa Marine Shale (TMS) was deposited across southern Louisiana and Mississippi during the Upper Cretaceous. The study focuses on a core region containing vast deposits of Cretaceous-aged sediments that have economic importance for oil and gas exploration. This region has been conventionally drilled for decades, focusing on the recovery of the Cretaceous hydrocarbons. Explorers within this region had traditionally targeted the massive sand units of the Lower and Upper Tuscaloosa Group while neglecting the middle Tuscaloosa Marine Shale unit. With the onset of unconventional drilling technology, new explorers to the region have begun to delineate the Tuscaloosa Marine Shale’s …

Basic Meteorological Data Derived 30-Year Normas (1981-2010) Of Actual Evapotranspiration Rates In Nebraska, Usa, Jozsef Szilagyi

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti

International Journal of Speleology

Over the past 15 years several expeditions by French, American and especially Italian cavers have unveiled over 50 caves in the Cordillera de la Sal (Atacama Desert, Northern Chile). Many of these caves contain a variety of speleothems and minerals, some of which have rarely been observed within karst systems. Most of the secondary deposits in these caves are composed of halite, but also other halide, carbonate, sulphate, nitrate, phosphate, and silicate minerals have been found. Among the sixteen cave mineral species recognized, atacamite, darapskite, blödite, leonite, anhydrite, and especially antarcticite are worth mentioning. In one of the samples an …

Effects Of Spatially Distributed Stream Power On Check Dam Function In Small Upland Watersheds: A Case Study Of The Upper Laja Watershed, Guanajuato, Mexico, Zachary Andrew Herzfeld

Dissertations and Theses

Watershed restoration comes in a variety of forms depending on which set of problems are sought to be remedied. Severe soil erosion, in the form of gullying and/or headcutting, can be mitigated through constructing check dams in well-selected locations. This practice has been used throughout the upland subwatersheds within the Upper Laja River watershed in Guanajuato, México. The present study employed Wolman pebble counts to systematically assess the effectiveness of 21 check dams located near the city of San Miguel de Allende. Particle size distributions taken directly downstream and upstream of each check dam were differentiated, aggregated and compared--with the …

Petrographical And Geochemical Changes In Bosnian Stalagmites And Their Palaeo-Environmental Significance, Veronica Chiarini, Isabelle Couchoud, Russell Drysdale, Petra Bajo, Simone Milanolo, Silvia Frisia, Alan Greig, John Hellstrom, Jo De Waele

International Journal of Speleology

Detailed petrographic observations have been coupled with trace element and δ¹³C - δ¹⁸O analyses in order to investigate their dynamics in two Holocene Bosnian speleothems. The potential of this multiproxy approach in providing a means to extract palaeo-environmental information from stalagmites whose stable isotope signals are noisy and without obvious trends has been tested. The studied stalagmites are mostly characterized by columnar microcrystalline fabric. At the sub-millimetre scale of lamination, different microcrystalline columnar sub-types (open and closed) have been detected and classified on the basis of the observed porosity and the crystallite size. The presence of …

2016/17 Dry Run Creek Geomorphological Watershed Assessment, University Of Northern Iowa. Department Of Earth And Environmental Sciences.

UNI Conservation Corps Projects

Dry Run Creek (DRC) watershed is a primary drainage basin located in northwestern Black Hawk County (Figure 1). It is fed predominantly by agricultural runoff in its upper reaches, and becomes heavily urbanized as it travels through the city of Cedar Falls, before draining into the Cedar River. The stream is perennial, however some are tiled and new segments have developed both naturally and artificially. Re-evaluation of the creek is underway and indicates some changes in urban and rural areas. Data was collected between Fall 2016 & Fall 2017 by University of Northern Iowa geomorphology students, using handheld GPS devices …

Nebraska, Usa: Wonderful Fossils, Natural History Museums And Public Art Depicting Fossils, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Nebraska is known by vertebrate palaeontologists as the place in North America where there is a very complete Cenozoic geologic record of mammalian evolution over the last thirty-five million years or so. All you have to do is visit any of the many major natural history museums in the USA and in many countries around the world, including the UK, to see fossil skulls, articulated skeletons and large slabs of rock containing bones of fossil mammals from Nebraska to verify this assertion. Nebraska is also the site of Cretaceous rocks containing the oldest known Cretaceous fossil flower and many other …

Novel Methods For Quantifying Spatio-Temporal Change In Glaciated And Subaqueous Environments, Jordan Mertes

Dissertations, Master's Theses and Master's Reports

In many scientific fields, it is important to actively develop new approaches to monitoring and quantifying changes within different systems. Often adapting existing tools or applying techniques from alternative fields can greatly improve our ability to monitor spatial and temporal changes. In this dissertation, I present four studies aimed at demonstrating new innovative ways at improving our ability to observe and quantify changes occurring on glaciers, submerged cultural resources (SCRs) and supraglacial lakes by using technology such as Structure from Motion + Multi-view stereo photogrammetry (SfM) and ground penetrating radar (GPR) surveying combined with facies analysis.

I have successfully reconstructed …

Morpho-Sedimentary Characteristics Of Proximal Gravel Braided River Deposits In A Froude-Scaled Physical Model, Peter Ashmore, Tobias Gardner, Pauline Leduc

Geography & Environment Publications

A Froude‐scaled physical model of a proximal gravel‐bed braided river was used to connect the river morphological characteristics, and sedimentary processes and forms, to deposit geometry. High resolution continuous three‐dimensional topographic data were acquired from sequential photogrammetric digital elevation models paired with grain‐size surface maps derived from image analysis of textural properties of the surface. From these data, the full three‐dimensional development of the braided river deposit and grain‐size sorting patterns was compiled over an experimental time period of 41 h during which the model river reworked a large portion of the braided channel. The minimum surface of the deposit …

Natural And Human-Induced Variability In Barrier-Island Response To Sea Level Rise, Jennifer Miselis, Jorge Lorenzo Trueba

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Storm-driven sediment fluxes onto and behind barrier islands help coastal barrier systems keep pace with sea level rise (SLR). Understanding what controls cross-shore sediment flux magnitudes is critical for making accurate forecasts of barrier response to increased SLR rates. Here, using an existing morphodynamic model for barrier island evolution, observations are used to constrain model parameters and explore potential variability in future barrier behavior. Using modeled drowning outcomes as a proxy for vulnerability to SLR, 0%, 28%, and 100% of the barrier is vulnerable to SLR rates of 4, 7, and 10 mm/yr, respectively. When only overwash fluxes are increased …

2016 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach, Connie Reimers-Hild

Conservation and Survey Division: Faculty and Staff Publications

The effective management of Nebraska’s water resources is evermore challenged by variations in weather, climate, technology, socioeconomic policies, and regulation. Anthropogenic climate change, declining water tables and stream flows, increasing demands on freshwater, aging water infrastructure, fiscal constraints, and impacts on aquatic organisms are particularly imminent challenges in Nebraska and around the world (Pahl-Wostl et al., 2013; Pittock et al., 2008; USACE, 2010). Sustaining freshwater ecosystem services in the face of emerging environmental threats presents an immense societal dilemma worldwide (Pittock et al., 2013; Rockström et al., 2009, Millenium Ecosystem Assessment, 2005). The rapidly changing conditions of water resources in …

Application Of Agisoft Photoscan And Sediment Transport Modeling For The Analysis Of Sediment Wave Propagation Succeeding Gravel Augmentation, Oak Grove Fork Of The Clackamas River, Oregon, Mindi Lea Curran

Cal Poly Humboldt theses and projects

Application of agisoft photoscan and sediment transport modeling for the analysis of sediment wave propagation succeeding gravel augmentation, oak grove fork of the clackamas river, oregon

Mindi Lea Curran

Physical features in alluvial rivers such as riffles, gravel bars, pools, and side channels provide refugia, nutrients, and spawning and rearing habitat for anadromous fish and other aquatic organisms. The downstream transport of gravels that continuously replenish these features is prevented by dams, and often leads to a coarsened channel bed condition and other geomorphic changes that have negative impacts on aquatic organisms. Geomorphic change in rivers can be challenging to …

Nebraska Statewide Groundwater-Level Monitoring Report 2016, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Michele M. Waszgis, R. Matthew Joeckel, Sue Olafsen Lackey

Conservation and Survey Division: Faculty and Staff Publications

The term “groundwater” has come to be all but synonymous with Nebraska. Nearly three-quarters of the volume of the High Plains aquifer lies beneath the State, and groundwater maintains our streams, our ecosystems, our people, and our vitally important agricultural economy. Although Nebraska’s total groundwater resource is vast, it is also quite vulnerable to changes induced by natural processes and by humankind, necessitating a long-term commitment to wise management through informed decision making. Monitoring, studying, and reporting are the essential basis for such management and, ultimately, for meeting the myriad challenges presented by change.

The personnel of the Conservation and …

Sedimentary Responses To Growth Fault Slip And Clay Shrink And Swell Induced Elevation Variations: East Matagorda Peninsula, Texas, Wei Ji

Theses and Dissertations--Earth and Environmental Sciences

East Matagorda Peninsula in southwestern Texas is characterized geologically by active, regional-scale and near-surface growth faulting. Decimeter scale (up to 0.42 m) vertical displacement was recorded at the study site over a period of four years, not believed to be associated with growth faulting. This research tested the hypotheses that fault slip rates were correlated with sediment accumulation rates, and that the observed vertical displacement was produced by shrink-and-swell clays in near surface sediments. To quantify sediment accumulation rates, a suite of radionuclides (⁷Be, ¹³⁷Cs, and ²¹⁰Pb) were used. To understand the effects of shrink-and-swell clays, …

Fluvial-Lacustrine Processes Shaping The Landforms Of The Distal Paraguay Fluvial Megafan, Edward Limin Lo

Theses and Dissertations--Earth and Environmental Sciences

Tropical wetlands such as the Pantanal help regulate global biogeochemical cycles, but climate change is modifying these environments. Controls on environmental changes can potentially be assessed from ancient, well-dated lacustrine sedimentary records. An integrated field and laboratory approach was undertaken to study the limnogeology of Lake Uberaba in the northern Pantanal, and test whether the lake has preserved a reliable record of environmental change in its strata. This study was designed to understand how the basin accumulates sediment and to assess its sensitivity to hydroclimatic variability. The data showed that modern Lake Uberaba is a highly dynamic, freshwater fluvial-lacustrine basin. …

Data Potential Of Archaeological Deposits At The Chelan Station Site, Matthew J. Breidenthal

All Master's Theses

The Chelan Station Site (45CH782/783), located along the Rocky Reach of the Columbia River, includes lithic and faunal artifacts buried beneath volcanic tephra from Mt. Mazama (6,830 BP). Artifacts were inadvertently discovered in buried soils within a secondary alluvial terrace during construction of a pipeline to supply water to the Beebe Springs Fish Hatchery. This thesis stems from participation in original field work and includes the author’s own models of early land forms and site formation. The study reviews the construction monitoring and archaeological testing of both sites, and documents the archaeological data potential early occupations of the vicinity. The …

Catastrophic Landscape Modification From Massive Landslide Tsunamis: An Example From Taan Fiord, Alaska, Colin Bloom

All Master's Theses

The October 17^th 2015 Taan landslide and tsunami generated a high runup of 192 m, nearly an order of magnitude greater than most previously surveyed tsunamis. Extensive modifications observed and documented on several low gradient fan deltas within the fiord make Taan Fiord an excellent laboratory for characterizing geomorphic signatures of a high runup tsunami event. Although interest in this topic is high, most prior post-tsunami surveys are from earthquake-generated tsunamis with relatively low runup, thus the geomorphic signatures of high runup tsunamis or their potential for preservation are uncharacterized. Additionally, clear modifications described during post-tsunami surveys are typically …

A Quantitative Analysis Of The Fretted Terrain Valleys, Arabia Terra, Mars, Kelsey Anne Mason

Open Access Theses & Dissertations

Fretted terrain describes regions on Mars with low-lying, flat valleys separated by steep cliffs that often form polygonal-shaped mesas. The fretted terrain valleys have a morphology distinct from other valleys found on Mars, and their unknown origin may hold insights into critical questions about Mars' tectonic, magmatic, and hydrologic history. Current hypoThesis for the formation of the fretted terrain include fracturing as well as hydrological flow processes such as fluvial or glacial erosion. The region for this study is located in eastern Arabia Terra and is the type-location for fretted terrain. By qualitatively and quantitatively documenting the planform, or map-view, …

Quantifying Ephemeral Gully Erosion With Photogrammetry Surveying, C. B. Weerasekara, A. Y. Shechukov

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Surface Offset And Slip Rates For The Winter Rim Fault System In The Summer Lake Basin, Oregon, Jennifer Hall

All Master's Theses

The 66-km-long Winter Rim Fault (WRF) system, located in the northwestern Basin and Range Province, encompasses several Holocene fault scarps within the Summer Lake basin that include the WRF system, a normal fault divided into three segments: Slide Mountain (SMF), Winter Ridge, and Ana River (ARF), and the newly-mapped Thousand Springs fault (TSF). The current least-compressive stress field is oriented ~264° (Crider, 2001). The USGS estimates a slip rate of 0.43 mm/yr, earthquake magnitudes of 6.5-7.19, and recurrence interval of 3.1 ka (Crone et al., 2009). However, these estimates are only based upon ARF and the unfavorably slip-oriented SMF. With …

The Ribbed Drapery Of The Puerto Princesa Underground River (Palawan, Philippines): Morphology And Genesis, Paolo Forti, Giovanni Badino, Jose Maria Calaforra, Jo De Waele

International Journal of Speleology

During the 2011 speleological expedition to the Puerto Princesa Underground River (Palawan, Philippines) a drapery characterized by several close-to-horizontal ribs has been noticed. Even without sampling and analyzing its internal growth layers, a detailed morphological study allowed to present a possible genetic model. The presented model helps to explain its evolution, which is mainly controlled by variation in water flow as a consequence of the Palawan climate. When validated by further analyses, the same genetic mechanism could define also the evolution of the very common but still unexplained complex flowstones, which exhibit several close-to-horizontal steps, widenings and narrowings along their …