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2021

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Articles 1 - 30 of 76

Full-Text Articles in Geomorphology

Paleoindian Response To Climate Change In The Northern Jornada Del Muerto, Christopher Wayne Merriman Dec 2021

Paleoindian Response To Climate Change In The Northern Jornada Del Muerto, Christopher Wayne Merriman

Anthropology ETDs

Human-environment interaction is a long-standing and productive line of inquiry that includes the study of cultural responses to climate change. However, demonstrating a causal relationship between climate change and the consequent culture change is rarely straightforward for numerous reasons. In this dissertation I develop an optimality model to predict how Paleoindians should have responded to changes in precipitation across the Late Pleistocene-Early Holocene. The water supply model (WSM) ranks water supplies much like the diet breadth model ranks food resources. To adjust the WSM for climate change, paleoclimate records from playas in the northern Jornada del Muerto were used in …


Fine Grained Delta Front Sediment Transport, Sarah Noel Dec 2021

Fine Grained Delta Front Sediment Transport, Sarah Noel

LSU New Orleans Theses and Dissertations

Insights into transformative coastal processes are unlocked though understanding sediment transport mechanisms in fine-grained delta front environments. Movement of fine-grained sediments on delta fronts is not wholly explained through advection settling models. While advection settling models generally assume deposition into a still body, numerical modeling of sediment re-entrainment suggests there may be tidal, wave, and/or non-steady hydrograph influences allowing particles to reach greater distances by altering the decelerating velocity field. This research explores both an advection settling model and a mass conservation Rouse profile model to understand the irreducible delta front processes controlling sediment deposition. Using field data collected on …


Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton Dec 2021

Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton

Mechanical Engineering Undergraduate Honors Theses

River channels have been observed near the Huygens probe landing site on the surface of Titan, along with evidence of rounded water ice boulders transported through fluid flow. Evidence near the landing site suggests active flow of liquid methane, which has motivated the study of the effects of sediment load and channel sizes on Titan’s fluvial features. A numerical model is used to determine the viscosity, flow velocity, and critical boulder transport diameter based on channel size, slope, and a range of sediment concentrations. This model achieves two ends: first, observed boulder diameters are used to determine the ideal channel …


The Morphodynamic Interaction Of River Deltas And Their Marshes, Kelly M. Sanks Dec 2021

The Morphodynamic Interaction Of River Deltas And Their Marshes, Kelly M. Sanks

Graduate Theses and Dissertations

Globally, many of the largest river deltas contain vast marsh platforms that are currently threatened due to a combination of anthropogenic alterations to rivers and increasing relative sea level rise. Restoration and management plans for river deltas depend on optimizing riverine sediment accumulation in marsh platforms. However, the accumulation of organic material in marsh platforms is often neglected in predictive models and the interaction of ecogeomorphic processes governing marsh accumulation with the physical processes governing river delta growth is poorly understood.

Herein, I investigate this complex relationship through a combination of field and experimental studies. I show that in coastal …


Speleogenesis In A Lens Of Metamorphosed Limestone And Ankerite: Ochtiná Aragonite Cave, Slovakia, Pavel Bella, Pavel Bosák, Petr Pruner, Helena Hercman, Katarína Pukanská, Karol Bartoš, Ľudovít Gaál, Dagmar Haviarová, Peter Tomčík, Šimon Kdýr Nov 2021

Speleogenesis In A Lens Of Metamorphosed Limestone And Ankerite: Ochtiná Aragonite Cave, Slovakia, Pavel Bella, Pavel Bosák, Petr Pruner, Helena Hercman, Katarína Pukanská, Karol Bartoš, Ľudovít Gaál, Dagmar Haviarová, Peter Tomčík, Šimon Kdýr

International Journal of Speleology

The Ochtiná Aragonite Cave (Western Carpathians) represents an unique natural phenomenon. It originated under particular lithological and hydrogeological conditions of the Ochtiná Karst in which several isolated lenses of Paleozoic crystalline limestone (marbles), partly metasomatically altered to ankerite, are enclosed by phyllites. Meteoric water seepage through non-carbonate rocks dissolved limestone and caused the oxidation of ankerite to Fe oxyhydroxides. Carbon dioxide produced during ankerite oxidation enhanced limestone dissolution. The maze cave consists of parallel fault-controlled linear passages and chambers interconnected by transverse horizontal passages. Phreatic and epiphreatic solution morphologies resulted from slowly moving or standing water. These include flat ceilings …


Silica Sinter And The Evolution Of Hot Springs In The Alvord/Pueblo Valleys, Southeast Oregon, Usa, Leslie Allen Mowbray, Michael L. Cummings Nov 2021

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 …


The Importance Of Lithologic Variability And Stratigraphic Architecture In The Development Of Eogenetic Karst Systems, Nicholas J. Soto-Kerans Oct 2021

The Importance Of Lithologic Variability And Stratigraphic Architecture In The Development Of Eogenetic Karst Systems, Nicholas J. Soto-Kerans

USF Tampa Graduate Theses and Dissertations

Integrative characterizations of karst systems on low-lying eogenetic carbonate platforms are rare and often limited to areas of direct observation where caves can be entered and explored. Because hydraulic properties of eogenetic limestones have been implicitly assumed to be homogeneous, classical models of carbonate island karst development stressed the importance of geochemical interfaces in controlling cave and vug development. These studies have explained the largest cavern systems as results of either 1) mixing dissolution at platform margins or 2) microbially-mediated dissolution processes at water tables.

New data from core descriptions and wireline logs obtained in 18 boreholes drilled in the …


Assessing Morphological Response And Vulnerability Of Barrier Islands To Extreme Storms In Northwest Florida, Jacob Adam Oct 2021

Assessing Morphological Response And Vulnerability Of Barrier Islands To Extreme Storms In Northwest Florida, Jacob Adam

USF Tampa Graduate Theses and Dissertations

Barrier islands shield the mainland coast from the effects of extreme storms such as increased wave energy and storm surge. During these events, however, barrier morphology can be altered by erosive forces. Thus, compromising the protection offered and leading to increased impact on the mainland. The St. Joseph Peninsula, located in the Northwest of the Gulf of Mexico, is one such barrier at threat from storm-induced erosion. Presented here is an assessment of morphology change induced by two major storms to impact the peninsula, Hurricanes Dennis 2005 and Michael 2018. These changes characterize the erosive/depositional patterns that can be expected …


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 Oct 2021

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: Faculty and Staff Publications

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 …


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 Oct 2021

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 Oct 2021

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 …


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 Oct 2021

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 …


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 Oct 2021

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: Faculty and Staff Publications

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 …


The Morphology And Evolution Of Transverse Aeolian Ridges On Mars, Timothy Paul Nagle-Mcnaughton Oct 2021

The Morphology And Evolution Of Transverse Aeolian Ridges On Mars, Timothy Paul Nagle-Mcnaughton

Earth and Planetary Sciences ETDs

Transverse aeolian ridges (TARs) are enigmatic and largely relict bedforms on the surface of Mars. TARs are sparsely distributed but common on Mars, but their history, preservation, and past role in the sediment cycle is not well understood. First described in 2003, and detailed extensively in 2008, our study of TARs has been narrowly focused in the last decade, with more and more research noting their presence, but little investigation of the features themselves. Recent work has mostly focused on identifying Terran analogues for TARs, but TARs remain largely a unique Martian feature. In this manuscript, I clarify and refine …


Molecular Genetic Analysis Of Stygobiotic Shrimps Of The Genus Xiphocaridinella (Crustacea: Decapoda: Atyidae) Reveals A Connection Between Distant Caves In Central Abkhazia, Southwestern Caucasus, Ivan Marin, Ilya Turbanov Sep 2021

Molecular Genetic Analysis Of Stygobiotic Shrimps Of The Genus Xiphocaridinella (Crustacea: Decapoda: Atyidae) Reveals A Connection Between Distant Caves In Central Abkhazia, Southwestern Caucasus, Ivan Marin, Ilya Turbanov

International Journal of Speleology

Based on the morpho-genetic study of stygobiotic shrimps from the genus Xiphocaridinella Sadowsky, 1930 (Crustacea: Decapoda: Atyidae), a hydrogeological connection of a number of distant caves in Central Abkhazia of the southwestern Caucasus is satisfied, which indicates the possibility of using biospeleological studies in some cases to identify karst hydrosystems together with traditional hydrogeological methods. Moreover, a new stygobiotic atyid shrimp from the genus Xiphocaridinella, X. kelasuri sp. n., is described based on morphology and analysis of mitochondrial cytochrome oxidase I DNA sequences from three distant caves. The new species is genetically divergent from relatives and phylogenetically related to …


Evaluating The Controls Of Neogene Exhumation In The Tropical Northern Andes (Colombia), Nicolas Perez Consuegra Aug 2021

Evaluating The Controls Of Neogene Exhumation In The Tropical Northern Andes (Colombia), Nicolas Perez Consuegra

Dissertations - ALL

Understanding how tectonic and climatic forces influence erosion and shape mountains is important to understand the evolution of the landscapes through earth's history. This dissertation aims to determine how do tectonic processes and climate variability interact to shape Earth's tropical mountains. In chapter 1, I studied the Eastern Cordillera of the Northern Andes, a mountain range located in Colombia in the tropics of South America. To obtain exhumation rates, I used thermochronology, which is a method that records—over timescales of millions of years—the rate at which rocks located at great depths within the Earth cool as they are transported to …


Ensemble Data Fitting For Bathymetric Models Informed By Nominal Data, Samantha Zambo Aug 2021

Ensemble Data Fitting For Bathymetric Models Informed By Nominal Data, Samantha Zambo

Dissertations

Due to the difficulty and expense of collecting bathymetric data, modeling is the primary tool to produce detailed maps of the ocean floor. Current modeling practices typically utilize only one interpolator; the industry standard is splines-in-tension.

In this dissertation we introduce a new nominal-informed ensemble interpolator designed to improve modeling accuracy in regions of sparse data. The method is guided by a priori domain knowledge provided by artificially intelligent classifiers. We recast such geomorphological classifications, such as ‘seamount’ or ‘ridge’, as nominal data which we utilize as foundational shapes in an expanded ordinary least squares regression-based algorithm. To our knowledge …


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 Aug 2021

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 (TOCSOM), and porewater salinity) using hierarchical clustering and ordination. While no single variable consistently explains variations in diatom assemblages …


Historical Changes Of Channel Width In A Headwater Stream System, Mark Twain National Forest, Missouri, Sierra N. Casagrand Aug 2021

Historical Changes Of Channel Width In A Headwater Stream System, Mark Twain National Forest, Missouri, Sierra N. Casagrand

Graduate Theses/Dissertations

It is well known that watershed disturbances due to land clearing and agricultural settlement during the early 1800s changed the hydrology and geomorphology of stream systems in the Midwestern USA. However, little is known about the impacts of historical logging on stream systems in forested watersheds. This study evaluates channel width measurements from 38 General Land Office (GLO) surveys completed in 1821, aerial photographs from the 1930’s to present, and LiDAR imagery from 2016/17 to evaluate changes in channel morphology in Big Barren Creek in Mark Twain National Forest in the Ozarks Highlands of southeast Missouri. The area was heavily …


Differences In Erosion Rates And Elevation Among Natural, Living And Hardened Shorelines In Mississippi, And Alabama, Brittany Juneau Aug 2021

Differences In Erosion Rates And Elevation Among Natural, Living And Hardened Shorelines In Mississippi, And Alabama, Brittany Juneau

Honors Theses

Shoreline erosion is a phenomenon that currently threatens both natural ecosystems and human settlements along the coast. With trends showing gradual sea level rise as a result of climate change, erosion is becoming an increasing threat to these communities. This research aims to provide more insight into the relationship between shoreline morphology and three shoreline protection techniques: natural marsh, living shoreline, and hardened structures. Six sites along the Alabama and Mississippi coast that had all three shoreline types were evaluated to determine what the average erosion rate and slope was for each shoreline. Erosion rates were calculated by image analysis …


Exploring Questions Of Tectonic Geomorphology In The Bear River Range, Utah Using Terrain Analysis And Reconstruction, Edward M. Grasinger Aug 2021

Exploring Questions Of Tectonic Geomorphology In The Bear River Range, Utah Using Terrain Analysis And Reconstruction, Edward M. Grasinger

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Despite a long tradition of geologic studies in the region surrounding Utah State University, there remain unexplored questions and unutilized approaches for understanding the landscape evolution of the Bear River Range. A large-scale reconstruction of the East Cache fault system can be useful in estimating the total displacement of the fault, its geologic longevity, and total energy involved. Likewise, an analysis of reach-scale features of the Logan River can explore how tectonics and bedrock type affect the patterns and history of the river. Geographic Information Systems (GIS) software is useful in reconstructing, visualizing, and measuring such geomorphological features and changes …


Using An Inventory Of Unstable Slopes To Prioritize Probabilistic Rockfall Modeling And Acid Base Accounting In Great Smoky Mountains National Park, Thomas A. O'Shea Aug 2021

Using An Inventory Of Unstable Slopes To Prioritize Probabilistic Rockfall Modeling And Acid Base Accounting In Great Smoky Mountains National Park, Thomas A. O'Shea

Electronic Theses and Dissertations

An inventory of unstable slopes along transportation corridors and performance modeling are important components of geotechnical asset management in Great Smoky Mountains National Park (GRSM). Hazards and risk were assessed for 285 unstable slopes along 151 miles of roadway. A multi-criteria model was created to select fourteen sites for two-dimensional probabilistic rockfall simulations and Acid Base Accounting (ABA) tests. Simulations indicate that rock material would likely enter the roadway at all fourteen sites. ABA test results indicate that influence of significant acid-producing potential is generally confined to slaty rocks of the Anakeesta Formation and graphitic schist of the Wehutty Formation. …


The Impacts Of Climate And Landscape Change On Catchment Scale Material Transport In High Mountain And Seasonally Cold Regions, John R. Slosson Jul 2021

The Impacts Of Climate And Landscape Change On Catchment Scale Material Transport In High Mountain And Seasonally Cold Regions, John R. Slosson

Dissertations - ALL

Streamflow in high mountain and seasonally cold regions follows annual patterns that can make water quality and availability in these areas uniquely susceptible to changes in climate and land use. Precipitation in the form of snow accumulates during the winter months and gradually melts in the spring, leading to elevated streamflow that serves important ecological and human needs. This simple winter storage and spring release dynamic is especially sensitive to warming temperatures, which can result in a greater fraction of winter precipitation falling as rain and an earlier arrival of the hydrograph center of timing, with cascading effects on surrounding …


Leveraging Natural Resources Toward Resilience: Outreach, Restoration, And Monitoring For A Resilient Nh Coast, Alyson Eberhardt, David M. Burdick, Gregg E. Moore Jul 2021

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 …


Modeling And Measuring Water Level Fluctuations In The Greenland Ice Sheet: How Moulin Life Cycle And Shape Can Inform Us On The Subglacial Drainage System., Celia Trunz Jul 2021

Modeling And Measuring Water Level Fluctuations In The Greenland Ice Sheet: How Moulin Life Cycle And Shape Can Inform Us On The Subglacial Drainage System., Celia Trunz

Graduate Theses and Dissertations

In the ablation zone of land terminating sectors of the Greenland Ice Sheet (GrIS), water pressures at the bed control ice motion variability on diurnal and seasonal timescales. During the melt season, large volumes of surface meltwater access the ice-bed interface through moulins.Moulins are large vertical shafts that connect the supraglacial and subglacial drainage systems. Moulins form when a crevasse intersects a surface meltwater source that can drive hydrofracture to the bed of the ice sheet. Upon reaching the bed, meltwater can establish and sustain an efficient, channelized drainage system. Due to the technical impossibility of physically exploring underwater passages …


Field And Remote Sensing Analysis Of The 2015 Pyroclastic Density Currents At Colima (Mexico) And Calbuco (Chile) Volcanoes: Implications For Hazard Assessment And Crisis Management, Elodie Macorps Jun 2021

Field And Remote Sensing Analysis Of The 2015 Pyroclastic Density Currents At Colima (Mexico) And Calbuco (Chile) Volcanoes: Implications For Hazard Assessment And Crisis Management, Elodie Macorps

USF Tampa Graduate Theses and Dissertations

Although one of the most spectacular phenomena of active volcanoes, Pyroclastic density currents, or PDCs, are considered the most dangerous volcanic hazards. PDCs are avalanches of hot volcanic gases, ash, and larger volcanic fragments that travel at incredible speed down the flank of a volcano. High dynamic pressures, high temperatures, and high velocities are the primary dangers associated with PDCs and lead to near-complete destruction and death.

I use a multi-disciplinary approach to study the deposits left behind by PDCs, in order to understand their dynamics, their interactions with the receiving landscape, and their final distribution, starting on the ground …


Ductile And Brittle Deformation Of Slackwater Deposits In The Tucannon River Valley, Chelsi K. Howard Jun 2021

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 Jun 2021

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 …


Resolving A One-Year Ecesis Interval For Alaska Paper Birch: Dating A Rockfall Event, Wishbone Hill, Southcentral Alaska, Riley E. Whitney, Alexander K. Stewart, Trent D. Hubbard, Anabella S. Kowalski, Oscar A. Wilkerson May 2021

Resolving A One-Year Ecesis Interval For Alaska Paper Birch: Dating A Rockfall Event, Wishbone Hill, Southcentral Alaska, Riley E. Whitney, Alexander K. Stewart, Trent D. Hubbard, Anabella S. Kowalski, Oscar A. Wilkerson

The Compass: Earth Science Journal of Sigma Gamma Epsilon

Numerous large boulders at the base of Wishbone Hill, northeast of Anchorage, Alaska, suggest a historic rockfall event and potential for future surface instability, putting lives and property at risk. The source of the rockfall-boulders is an exposed syncline with a cliff face composed of conglomerate. The age of trees growing atop boulders provides a minimum exposure-age of those boulders and, thus, the rockfall event. To determine when the rockfall occurred, we dated trees growing atop the boulders using tree-ring samples collected from 30 Alaska paper birch trees. After mounting and polishing, each tree-ring sample was dot-counted, and tree-ring widths …


Mineralogy Of Aeolian Deposits In Gale Crater, Mars: The Bagnold Dunes To Glen Torridon, Eleanor Moreland May 2021

Mineralogy Of Aeolian Deposits In Gale Crater, Mars: The Bagnold Dunes To Glen Torridon, Eleanor Moreland

Senior Honors Papers / Undergraduate Theses

We select four sand deposits along the traverse of the Curiosity rover to evaluate the spatial distribution of mineralogy and grain size. While extensive work has focused on characterizing the Bagnold Dunes in-situ and from orbit, less attention has been given to deposits south of the Vera Rubin Ridge (VRR). Overall, our results illustrate a compositional dichotomy among aeolian deposits, separated by the VRR. Initial investigations of hyperspectral data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) show differences in the long wavelength spectral features and absolute reflectance measurements for the deposit south of the Bagnold Dunes. The southern …