Geomorphology Commons^™

Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya

Department of Earth, Environment and Sustainability Faculty Publications

Meltwater runoff modeling from glacierized basins needs several input data, including total meltwater contributing area. This study utilizes optical remote sensing data to assess glacierized basins in the central Himalayas where snow and glaciers contribute substantially to the water resources. Result shows that there are four main water-bearing zones in the basin: (a) dry snow, (b) wet snow, (c) exposed glacial ice, and (d) debris-covered glacial ice, and it is possible to differentiate and map these zones and their spatio-temporal variations from satellite sensor data. These zones can then be incorporated in meltwater runoff modeling as separate entities because they …

Trap Efficiency Of A Silted Prairie Reservoir: Rapidan Reservoir, Blue Earth County, Minnesota, Katherine Brosch Rassmussen

All Graduate Theses, Dissertations, and Other Capstone Projects

Rapidan Dam and Reservoir are located along the Blue Earth River south of Mankato, Minnesota. The dam was constructed in 1911 as a source of hydroelectric power to supplement the surroundings communities. Currently, the reservoir is heavily silted and provides little hydroelectric benefit while proving costly to maintain. This study (1) defines the sedimentary, geomorphic, stream flow and suspended load characteristics of the reservoir for 2008-2009 and (2) compares these parameters with those available from 1985 (23 years prior). Stream gauging and sediment sampling took place in 2008 and 2009 at three monitoring locations (two upstream and one downstream of …

Holocene Arroyo Cut And Fills Cycles, South-Central Washington, Matthew Ian Durkee

All Master's Theses

Ephemeral streams have cut deeply incised arroyos into alluvial and eolian sediments in many of the watersheds within the Yakima Training Center (YTC) military reservation, south-central Washington. The most recent channel incision episode along Selah Creek is primarily attributed to multiple failures of an irrigation reservoir dam during the winters of 1909 and 1910. The modern arroyo exposed evidence of at least one previous episode of arroyo incision to a depth of ~4 m that occurred just prior to 1530- 1340 cal yr BP. Filling of this paleo-arroyo with fine to coarse grained sand ceased between 650-103 cal yr BP. …

Documenting Magma Evolution Of The Fossa Delle Felci (Salina Island, South Tyrrhenian Sea) By Integrating In Situ Plagioclase Data With Quantitative Modeling, Aaron Mayfield

All Master's Theses

Compositional diversity occurs via processes dominated by recharge, assimilation and fractional crystallization (RAFC), quantification of which can provide insights into eruption catalysts, and therefore assist in hazard mitigation. This study evaluates the relative roles of RAFC processes in Fossa delle Felci (Salina Island, Italy) magmas, which span the basalt to dacite range (52-65 wt% SiO2). Integration of petrographic, whole rock, and in situ plagioclase data with quantitative magma chamber models suggests differentiation dominated by fractional crystallization and magma recharge/mixing in reservoirs located at different crustal levels. At ~12 km depth, magma evolved through crystallization of a pyroxene dominated assemblage; plagioclase …

Petrogenetic Relationship Of The Postcaldera Eruptions Of Mount Mazama, Crater Lake, Oregon; Evolution Of A Sub-Volcanic Magma Chamber Following A Large Silicic Eruption, Michelle Leanna Tebbe

All Master's Theses

Mount Mazama is the volcanic edifice that cataclysmically erupted ~503 km of relatively homogeneous rhyodacite lava ~ 7,700 years ago, forming the caldera known as Crater Lake. Within a few hundred years, andesitic eruptions built three distinct volcanic edifices on the floor of Crater Lake; ~ 3000 years later, rhyodacite eruptions formed a dome (Bacon et al., 2002). How magmatic systems evolve following a shallow, relatively large silicic eruption is the focus of this study. In situ geochemical analysis coupled with high-resolution textural images of plagioclase crystals in the four postcaldera volcanic edifices were used to identify distinct crystal populations …

Documenting Magnatic Processes At Filicudi Island, Aeolian Arc, Italy: Integrating Quantitative Modeling And Plagioclase Textural And In Situ Compositional Data, Michelle Harris

All Master's Theses

Documenting the physiochemical processes that influence magma composition is critical for forecasting eruption styles and managing volcanic hazards. Compositional diversity of magmas develops through recharge, assimilation, and fractional crystallization (RAFC) within subvolcanic magma reservoirs. Integration of MELTS modeling, whole rock, plagioclase textural and in situ elemental and isotopic data from Filicudi Island, Italy allow documentation of the roles and relative chronology that RAFC played in the magmatic evolution and elucidates aspects of the magma plumbing system structure.

Results indicate a polybaric magma plumbing system with deeper (3.5-4 kilobars) and shallower (0.5-1.2 kilobars) storage regions. Within the deeper system, FC acted …

Grain Size Distribution With Geomorphology On Gypsum Dunes In The White Sands Erg, White Sands National Monument, New Mexico, Slade Jones

Open Access Theses & Dissertations

In order to examine grain size distribution over dunes at the White Sands dune field, 1214 geolocated surficial samples were collected and analyzed by laser diffraction. Local variations in dunes such as neighboring interdune types and the presence of vegetation, deflation features, and granule ripples on the dunes were noted. This study indicates that recrystallization of gypsum and the generation of fresh sediments is occurring in significant quantities within interdunes, providing both high and low anomalies in grain size distribution through much of the central portion of the dune field. Other local variations as previously mentioned such as scour surfaces …

Guidebook To The Geology Of The Platte River Valley Between Duncan And Schuyler, Nebraska, P.R. Hanson, Robert Matthew Joeckel, Aaron R. Young, Dana Divine, Jesse T. Korus Dr.

Conservation and Survey Division: Faculty and Staff Publications

The Platte River is considered to be a classic example of a braided stream, that is, a comparatively shallow stream with a high width:depth ratio.

Three Geologic Cross Sections Across Portions Of Eastern Nebraska Showing Quaternary Lithologic Units And Stratigraphy Of Uppermost Bedrock, Jesse T. Korus, Dana Divine, P. R. Hanson, J. S. Dillon

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Nebraska Statewide Groundwater-Level Monitoring Report 2011, Jesse T. Korus Dr., Mark E. Burbach, Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Nebraska Statewide Groundwater-Level Monitoring Report 2012, A. R. Young, M. E. Burbach, J. T. Korus, L. M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

A Large Cervidae Holocene Accumulation In Eastern Brazil: An Example Of Extreme Taphonomical Control In A Cave Environment, Alex Hubbe, Augusto S. Auler

International Journal of Speleology

A remarkable cervid bone accumulation occurs at a single passage (named Cervid Passage; CP) at Lapa Nova, a maze cave in eastern Brazil. CP lies away from cave entrances, is a typical pitfall passage and contains bone remains of at least 121 cervids, besides few bats, peccaries and rodents remains. There is no evidence of water (or sediment) flow at the site and in general bones lack post depositional alterations and display anatomical proximity, suggesting that the majority of the remains found inside CP (mainly cervids) are due to animals that after entering the cave got trapped in the site. …

Documenting The Origin Of Compositional Diversity Of Subduction Zone Magmatism, Alicudi, Aeolian Arc (Southern Tyrrhenian Sea, Italy) Using In Situ Plagioclase Data, Rachel Hunt

All Master's Theses

Processes that generate magma compositional diversity are important to document because composition affects degree of explosivity, which impacts hazard mitigation. Magnesium to silicon rich magmas are produced by processes such as magma recharge, assimilation, and fractional crystallization (RAFC) that occur in subvolcanic magma chamber(s). This study evaluates how magma chamber processes contribute to compositional diversity at Alicudi Volcano, Italy. Analytical and petrographic data from ten samples that span the subaerial history include whole rock major and trace elements and strontium/neodymium isotopes, and plagioclase textural types, major and trace elements, and strontium isotopes; numerical modeling was also conducted. Integration of these …

Scientific Drilling Of Speleothems – A Technical Note, Christoph Spötl, David Mattey

International Journal of Speleology

This short article provides detailed descriptions of custom-made and commercially available hand-held drilling gear and options for water-flushing units specifically designed to obtained good-quality core material from speleothems even in remote cave regions. We use small-diameter (6-7 mm) diamond drill bits to obtain aliquots of calcite (as little as a few hundreds of milligram) from the interior of the basal part of in-situ stalagmites. These small cores are used to date the onset of stalagmite growth and occasionally to obtain other compositional information. Larger diameter drill bits produce cores 25-32 mm in diameter and up to 1.3 m in length …

Cryogenic Fracturing Of Calcite Flowstone In Caves: Theoretical Considerations And Field Observations In Kents Cavern, Devon, Uk., Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Several caves in Devon, England, have been noted for extensive cracking of substantial flowstone floors. Conjectural explanations have included earthquake damage, local shock damage from collapsing cave passages, hydraulic pressure, and cryogenic processes. Here we present a theoretical model to demonstrate that frost-heaving and fracture of flowstone floors that overlie wet sediments is both a feasible and likely consequence of unidirectional air flow or cold-air ponding in caves, and argue that this is the most likely mechanism for flowstone cracking in caves located in Pleistocene periglacial environments outside of tectonically active regions. Modeled parameters for a main passage in Kents …

Corrosion Of Limestone Tablets In Sulfidic Ground-Water: Measurements And Speleogenetic Implications, Sandro Galdenzi

International Journal of Speleology

The measurement of the weight loss in limestone tablets placed in the Grotta del Fiume (Frasassi, Italy) provided data on the rate of limestone dissolution due to the sulfidic water and on the influence of local environmental conditions.

A linear average corrosion rate of 24 mm ka^-1 was measured in stagnant water, while the values were higher (68-119 mm ka^-1) where the hydrologic conditions facilitate water movement and gas exchanges. In these zones the increase in water aggressivity is due to mixing with descending, O₂-rich, seepage water and is also favored by easier gas exchange …

Natural And Anthropogenic Influences On The Morphodynamics Of Sandy And Mixed Sand And Gravel Beaches, Tiffany Roberts

USF Tampa Graduate Theses and Dissertations

Beaches and coastal environments are dynamic, constantly shaped and reshaped by natural processes and anthropogenic modifications. The morphodynamics and influence of natural and anthropogenic factors of two different coasts at various temporal and spatial scales are discussed.

To quantify the performance of several beach nourishment projects at annual temporal and kilometer spatial scales on three adjacent microtidal low-wave energy barrier islands in west-central Florida, a total of 5,200 beach and nearshore-profiles spaced at 300 m were surveyed monthly to bi-monthly from 2006-2010. Beach nourishment performance is most significantly influenced by the interruption of longshore sediment transport by complex tidal-inlet processes. …

Late Pleistocene And Holocene Aged Glacial And Climatic Reconstructions In The Goat Rocks Wilderness, Washington, United States, Joshua Andrews Heard

Dissertations and Theses

Eight glaciers, covering an area of 1.63 km2, reside on the northern and northeastern slopes of the Goat Rocks tallest peaks in the Cascades of central Washington. At least three glacial stands occurred downstream from these glaciers. Closest to modern glacier termini are Little Ice Age (LIA) moraines that were deposited between 1870 and 1899 AD, according to the lichenometric analysis. They are characterized by sharp, minimally eroded crests, little to no soil cover, and minimal vegetation cover. Glacier reconstructions indicate that LIA glaciers covered 8.29 km2, 76% more area than modern ice coverage. The average LIA equilibrium line altitude …