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The Depositional Environment Of The Triassic Cow Branch Formation, Dan River Basin Of Virginia And North Carolina Through Petrographic Study And Geochemical Analysis, And In Relation To Taphonomic Processes And Vertebrate Morphology, Gina M. Workman

All Graduate Reports and Creative Projects, Fall 2023 to Present

The Upper Triassic Cow Branch Formation of the Dan River Basin, located in southern Virginia and northern North Carolina, has long captivated generations of geoscientists. Since the 1970s, researchers have sought to unravel the mystery surrounding the depositional environment of this ancient lake system. This world-class lagerstätte hosts a diverse assemblage of fossil fauna and flora, with a notable preservation bias toward fossil vertebrates, most prominently the archosauromorph, Tanytrachelos ahynis. The geology of the Cow Branch strata continues to evoke a persistent question: Are these sediments representative of a shallow or deep lake?

I undertook a petrographic and geochemical study …

Primary Production Modeling Identifies Restoration Targets For Shifting Shallow, Eutrophic Lakes To Clear-Water Regimes, Leighton King, Janice Brahney, Scott Daly, Michael J. Paul, Kateri R. Salk, Soren Brothers

Watershed Sciences Faculty Publications

Benthic primary production (BPP) plays an important functional role in lakes, improving water quality by stabilizing clear-water regimes. Shallow, eutrophic lakes lacking BPP communities can be difficult to restore because self-stabilizing feedbacks of phytoplankton dominance can impede the establishment of BPP. BPP in lakes is light limited, and ecosystem models can provide guidance for determining the water clarity necessary to re-establish BPP dominance. We developed a multi-tiered framework for the restoration of shallow, eutrophic lakes that incorporates multiple turbidity sources, lake morphometry, and water-level fluctuations to determine water-clarity thresholds above which BPP dominance may be established. We present a case …

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 …

Spatial And Temporal Patterns Of River Incision And Terrace Deposition In Response To Climate And Tectonics In Southern Taiwan, Dominique M. Shore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geologists often look at the Earth’s surface to understand the underlying processes that cause mountain formation. As tectonic forces drive uplift of Earth’s surface, processes of erosion transport sediment to lower elevations. Climate can play a large role in landscape formation as well as increased precipitation, accelerating rates of erosion. Rivers leave markers of landscape evolution through terrace landforms, former river floodplains that are left behind when rivers incise into a valley. To better understand landscape response to uplift, this research investigated the initial linkages between uplift, hillslope erosion (mass wasting) and river incision. At some point, it is thought …

The Response Of Utah Lake's Plant And Algal Community Structure To Cultural Eutrophication, Leighton R. King

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Human activities have long had a negative impact on the water quality of freshwater lakes around the world. Utah Lake, located in north-central Utah, has been a subject of such impacts, as the lake experiences recurrent harmful algal blooms during the summer months. Lake warnings and closures have made the public increasingly aware of the ecological and economic impact of these blooms. The objectives of this study were to: 1) compare historical and present-day water quality and ecosystem conditions using environmental data contained in sediment cores, 2) identify whether, and when, Utah Lake transitioned from clearwater to turbid conditions, and …

Evolution Of The Book Cliffs Dryland Escarpment In Central Utah - Establishing Rates And Testing Models Of Escarpment Retreat, Nicholas R. Mccarroll

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the earliest explorations of the Colorado Plateau, geologists have suspected that cliffs are retreating back laterally. Clarence Dutton envisioned “the beds thus dissolving edge wise until after the lapse of millions of centuries their terminal cliffs stand a hundred miles or more back from their original position” when he wrote about the landscape in 1882. While many geologic studies have determined how fast rivers cut down through the Plateau, only a few studies have calculated how quickly cliffs retreat laterally, and geologists have been arguing since the 1940’s what exactly drives cliffs to retreat in the first place. We …

Evidence For Large Holocene Earthquakes Along The Denali Fault In Southwest Yukon, Canada, Andrée Blais-Stevens, John J. Clague, Janice Brahney, Panya Lipovsky, Peter J. Haeussler, Brian Menounos

Watershed Sciences Faculty Publications

The Yukon–Alaska Highway corridor in southern Yukon is subject to geohazards ranging from landslides to floods and earthquakes on faults in the St. Elias Mountains and Shakwak Valley. Here we discuss the late Holocene seismic history of the Denali fault, located at the eastern front of the St. Elias Mountains and one of only a few known seismically active terrestrial faults in Canada. Holocene faulting is indicated by scarps and mounds on late Pleistocene drift and by tectonically deformed Pleistocene and Holocene sediments. Previous work on trenches excavated against the fault scarp near the Duke River reveals paleoseismic sediment disturbance …

Investigating Patterns Of Fluvial Form And Incision Near The Yellowstone Hotspot — Alpine Canyon Of The Snake River, Wyoming, Daphnee Tuzlak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The shape of a landscape is created by rivers, which erode the underlying bedrock and carve through mountains. The Snake River flows across the uplifting hotspot plume of the Yellowstone region, cuts through the Snake River Range, and ultimately enters the low-lying eastern Snake River Plain. Although there is a good understanding of the track of the Yellowstone hotspot over geologic time and shorter timescales, measurements over Quaternary timescales and an understanding of how uplift influences the rivers and landscape in the Yellowstone region are absent. We study the Snake River and its past deposits where it cuts through Alpine …

Geologic Map Of The Lima Peaks 7.5' Quadrangle, Beaverhead County, Montana, Betty Skipp, William J. Perry Jr., Susanne U. Jänecke

Geosciences Faculty Publications

The Lima Peaks quadrangle is located in southwestern Beaverhead County in southwestern-most Montana, near the southern terminus of the Beaverhead Mountains (fig. 1). Rocks and deposits of Mississippian through Quaternary age are present along the eastern margin of the Cretaceous to early Tertiary Sevier fold-and-thrust belt. This area is structurally complex because rocks of older, Laramide Blacktail-Snowcrest uplift (Perry and others, 1988; Skipp, 1988; Lonn and others, 2006).

Ecological Changes In Two Contrasting Lakes Associated With Human Activity And Dust Transport In Western Wyoming, Janice Brahney, Ashley P. Ballantyne, P. Kociolek, P. R. Leavitt, G. L. Farmer, Jason C. Neff

Watershed Sciences Faculty Publications

The atmospheric transport and deposition of aerosols has the potential to influence the chemistry and biology of oligotrophic alpine lakes. In recent decades, dust and nitrogen emissions to alpine ecosystems have increased across large areas of the western U.S., including Wyoming. Here, we use sediment geochemistry and 87Sr/86Sr and 143Nd/144Nd isotopes to examine historical dust deposition rates to alpine lakes in the southwestern region of the Wind River Range, Wyoming. We evaluate the biological response using diatom fossil assemblages and sediment pigment concentrations. Sediment core analyses indicated that prior to a recent rise in dust flux, phosphorus concentrations and species …

Dust Mediated Transfer Of Phosphorus To Alpine Lake Ecosystems Of The Wind River Range, Wyoming, Usa, Janice Brahney, Ashley P. Ballantyne, P. Kociolek, Sarah A. Spaulding, Megan Otu, T. Porwoll, Jason C. Neff

Watershed Sciences Faculty Publications

Alpine lakes receive a large fraction of their nutrients from atmospheric sources and are consequently sensitive to variations in both the amount and chemistry of atmospheric deposition. In this study we explored the spatial changes in lake water chemistry and biology along a gradient of dust deposition in the Wind River Range, Wyoming. Regional differences were explored using the variation in bulk deposition, lake water, sediment, and bedrock geochemistry and catchment characteristics. Dust deposition rates in the Southwestern region averaged 3.34 g m−2 year−1, approximately three times higher than deposition rates in the Northwestern region (average 1.06 g m−2 year−1). …

Nutrient Contribution Of The Shallow Unconfined Aquifer To Pineview Reservoir, Thomas Nyanda Reuben

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pineview Reservoir, near Utah’s populous Wasatch Front, could play an important role in modulating water supply as water demands and water uses change in response to increasing population densities. The reservoir’s water quality may decline if nitrogen and phosphorus additions to the reservoir are not controlled. Most of the water flowing into the reservoir in summer and fall is contributed by the shallow ground water. The quantity and quality of the shallow ground water to Pineview Reservoir were studied from February 2010 through November 2011. The objectives were to: 1) increase understanding of nitrogen and phosphorus transport from ground water …

Earthquake Petrology: Linking Fault-Related Deformation To The Earthquake Cycle, Mitchell R. Prante

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Faults have a controlling influence on a variety of geologic processes including fluid flow, the mechanical behavior of the crust, and seismicity. The geologic sciences have long recognized that faults generate earthquakes; however, few indicators of ancient earthquakes exist in fault-zones. This dissertation documents several indicators for the preservation of ancient earthquakes in fault-zones including frictional melt (pseudotachylyte), highly-polished fault slip surfaces, and hydrothermal alteration.

These deformation products result from rapid generation of frictional heat during earthquakes. This dissertation also focuses on the seismic potential of continental low-angle normal faults (LANF). We document the preservation of voluminous pseudotachylyte along a …

Rock Properties And Structure Within The San Andreas Fault Observatory At Depth (Safod) Borehold, Northwest Of Parkfield, California: In Situ Observations Of Rock Deformation Processes And Fluid-Rock Interactions Of The San Andreas Fault Zone At ~ 3 Km Depth, Kelly Keighley Bradbury

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The San Andreas Fault Observatory at Depth (SAFOD) is a scientific drilling experiment situated along the central creeping segment of the San Andreas Fault, near Parkfield, California, and north of a segment of the fault that has experienced large historical earthquakes. Drilling into active fault zones allows scientist’s to examine in situ rock samples and to record real-time data.

The main goal of this study is to characterize the geologic setting and rock properties of the San Andreas fault at ~ 3 km depth in the SAFOD borehole. In this region, the fault deforms nearly continuously through aseismic creep and …

Geothermal Alteration Of Basaltic Core From The Snake River Plain, Idaho, Christopher Joseph Sant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Snake River Plain is located in the southern part of the state of Idaho. The eastern plain, which this study focuses on, is a trail of volcanics from the Yellowstone
hotspot. Three exploratory geothermal wells were drilled on the Snake River Plain. This project studies basaltic core from the first well at Kimama, north of Burley, Idaho. The objectives of this project are to establish zones of geothermal alteration and analyze the potential for geothermal power production near the center of the Snake River Plain. Thirty samples from 1,912 m of core were sampled and analyzed. Mineral data, temperature …

Lithology And Internal Structure Of The San Andreas Fault At Depth Based On Characterization Of Phase 3 Whole-Rock Core In The San Andreas Fault Observatory At Depth (Safod) Borehole, Kelly Keighley Bradbury, James P. Evans, J. S. Chester, F. M. Chester, D. L. Kirshner

Geosciences Faculty Publications

We characterize the lithology and structure of the spot core obtained in 2007 during Phase 3 drilling of the San Andreas Fault Observatory at Depth (SAFOD) in order to determine the composition, structure, and deformation processes of the fault zone at 3 km depth where creep and microseismicity occur. A total of approximately 41 m of spot core was taken from three separate sections of the borehole; the core samples consist of fractured arkosic sandstones and shale west of the SAF zone (Pacific Plate) and sheared fine-grained sedimentary rocks, ultrafine black fault-related rocks, and phyllosilicate-rich fault gouge within the fault …

Exploring Desert Stone, Steven K. Madsen

All USU Press Publications

The confluence of the Green and Colorado Rivers, now in Canyonlands National Park, near popular tourist destination Moab, still cannot be reached or viewed easily. Much of the surrounding region remained remote and rarely visited for decades after settlement of other parts of the West. The first U.S. government expedition to explore the canyon country and the Four Corners area was led by John Macomb of the army's topographical engineers. The soldiers and scientists followed in part the Old Spanish Trail, whose location they documented and verified. Seeking to find the confluence of the Colorado and the Green and looking …

Geophysical Properties Within The San Andreas Fault Zone At The San Andreas Fault Observatory At Depth (Safod) And Their Relationships To Rock Properties And Fault Zone Structure, Tamara N. Jeppson, Kelly Keighley Bradbury, James P. Evans

Geosciences Faculty Publications

We examine the relationships between borehole geophysical data and physical properties of fault‐related rocks within the San Andreas Fault as determined from data from the San Andreas Fault Observatory at Depth borehole. Geophysical logs, cuttings data, and drilling data from the region 3‐ to 4‐km measured depth of the borehole encompass the active part of the San Andreas Fault. The fault zone lies in a sequence of deformed sandstones, siltstone, shale, serpentinite‐bearing block‐in‐matrix rocks, and sheared phyllitic siltstone. The borehole geophysical logs reveal the presence of a low‐velocity zone from 3190 to 3410 m measured depth with V_p and …

High Geologic Slip Rates Since Early Pleistocene Initiation Of The San Jacinto And San Felipe Fault Zones In The San Andreas Fault System, Southern California, Usa, Susanne U. Janecke, R. J. Dorsey, D. Forand, A. N. Steely, S. M. Kirby, A. T. Lutz, B. A. Housen, B. Belgarde, V. E. Langenheim, T. M. Rittenour

Geosciences Faculty Publications

The San Jacinto right-lateral strike-slip fault zone is crucial for understanding plate-boundary dynamics, regional slip partitioning, and seismic hazards within the San Andreas fault system of southern California, yet its age of initiation and long-term average slip rate are controversial. This synthesis of prior and new detailed studies in the western Salton Trough documents initiation of structural segments of the San Jacinto fault zone at or slightly before the 1.07-Ma base of the Jaramillo subchron. The dextral faults changed again after ca. 0.5–0.6 Ma with creation of new fault segments and folds. There were major and widespread basinal changes in …

Arkosic Rocks From The San Andreas Fault Observatory At Depth (Safod) Borehole, Central California: Implications For The Structure And Tectonics Of The San Andreas Fault Zone, S. D. Springer, James P. Evans, J. I. Garver, D. Kirschner, Susanne U. Janecke

Geosciences Faculty Publications

The San Andreas Fault Observatory at Depth (SAFOD) drill hole encountered indurated, high-seismic-velocity arkosic sedimentary rocks west of the active trace of the San Andreas fault in central California. The arkosic rocks are juxtaposed against granitic rocks of the Salinian block to the southwest and against fine-grained Great Valley Group and Jurassic Franciscan rocks to the northeast. We identify three distinct lithologic units using cuttings, core petrography, electrical resistivity image logs, zircon fission-track analyses, and borehole-based geophysical logs. The upper arkose occurs from 1920 to 2530 m measured depth (mmd) in the borehole and is composed of five structural blocks …

Composition, Microstructures, And Petrophysics Of The Mozumi Fault, Japan: In Situ Analyses Of Fault Zone Properties And Structure In Sedimentary Rocks From Shallow Crustal Levels, Angela J. Isaacs, James P. Evans, Peter T. Kolesar, Tsuyoshi Nohara

Geosciences Faculty Publications

[1] We characterize the chemical, microstructural, and geophysical properties of fault-related rock samples from the 80–100 m wide Mozumi fault zone, north central Honshu, Japan. The fault is exposed in a research tunnel 300–400 m below the ground, and we combine geological data with borehole geophysical logs to determine the elastic and seismic properties of the fault zone. Detailed mapping within the tunnel reveals that the fault zone consists of two zones of breccia to foliated cataclasites 20 and 50 m thick. Two narrow (tens of centimeters wide) principal slip zones on which most of the slip occurred bound the …

The Geologic History Of Subsurface Arkosic Sedimentary Rocks In The San Andreas Fault Observatory At Depth (Safod) Borehole, Central California, Sarah D. Draper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The aim of the San Andreas Fault Observatory at Depth (SAFOD) project, a component of the NSF Earthscope Initiative, is to directly observe active fault processes at seismogenic depths through the drilling of a 3 km deep (true vertical depth) inclined borehole across San Andreas fault. Preliminary subsurface models based on surface mapping and geophysical data predicted different lithologies than were actually encountered. At 1920 meters measured depth (mmd), a sequence of well-indurated, interbedded arkosic conglomerates, sandstones, and siltstones was encountered. We present a detailed lithologic and structural characterization as a step toward understanding the complex geologic history of this …

Educational Policies Committee Program Proposal, College Of Science, June 9, 2006, Utah State University

Educational Policies Committee

Utah State University requests approval to offer a Master of Science Degree in Applied Environmental Geoscience in the Department of Geology effective Fall Semester 2006.

Educational Policies Committee Program Proposal, College Of Humanities And Social Sciences, June 9, 2006, Utah State University

Educational Policies Committee

Utah State University requests approval to offer a Bachelor of Science Degree in Agricultural Communication and Journalism through the Department of Agricultural Systems Technology and Education effective Fall 2006.

Evolution Of A Miocene-Pliocene Low-Angle Normal-Fault System In The Southern Bannock Range, Southeast Idaho, Stephanie M. Carney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geologic mapping, basin analysis, and tephrochronologic analysis in the Clifton quadrangle of southeast Idaho indicates that the modern Basin-and-Range topography is only a few million years old and that the bulk of Cenozoic extension was accommodated by slip on an older low-angle normal-fault system, the Bannock detachment system. The detachment system was active between ~12 and < 4 Ma and accommodated ~50 % extension.

Cross-cutting relationships show that the master detachment fault, the Clifton fault, is the youngest low-angle normal fault of the system, was active at a low angle, and has not been rotated to a low-dip angle through time. Map patterns and relationships indicate that the …

Geometry And Physical Properties Of The Chelungpu Fault, Taiwan, And Their Effect On Fault Rupture, Richard V. Heermance

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rupture of the Chelungpu fault during the September 21, 1999, 7.6 M_wearthquake in Taiwan caused a 90-Jr,m-long surface rupture with variable displacement along strike. Analysis of core from two holes drilled through the fault zone, combined with geologic mapping and detailed investigation from three outcrops, define the fault geometry and physical properties of the Chelungpu fault in its northern and southern regions. In the northern region, the fault dips 45-60° east parallel to bedding and consists of a narrow (1-20 cm) core of dark-gray, sheared clay gouge at the base of a 30-50 m zone of increased fracture …

Structural And Kinematic Evolution Of Eocene-Oligocene Grasshopper Extensional Basin, Southwest Montana, Julie C. Kickham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Grasshopper basin of southwest Montana is a complex east-dipping graben containing five unconformity-bounded sequences of Tertiary sedimentary rocks. The Eocene-Oligocene basin lies within the northern Rocky Mountain Basin and Range province. Geologic mapping in five and a half 7.5 minute quadrangles indicates that at least three distinct phases of extension characterize the Cenozoic tectonic evolution of Grasshopper basin from approximately 46 Ma to < Ma.

The significant phases of extension in Grasshopper basin were phases 1 and 3. During the first phase of extension (46-27 Ma) the nonplanar Muddy-Grasshopper fault was initiated and 90% of the basin fill was deposited. At …

Normal Faults And Extensional Folds Of Southwest Montana And Eastern Idaho, Susanne U. Janecke, J. J. Blankenau, C. J. Vandenburg, B. S. Van Gosen

Geosciences Faculty Publications

No abstract provided.

Late Quaternary Glacier Fluctuations And Vegetation Change In The Northwestern Ahklun Mountains, Southwestern Alaska, Yarrow L. Axford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research examines moraine and lacustrine records of glacier fluctuations, in combination with palynological records of vegetation change, from the previously unstudied northwestern Ahklun Mountains in southwestern Alaska.

Moraine mapping reveals that ice-cap outlet glaciers in the study area extended ca. 60 km from the center of the Ahklun Mountians ice dome during the early Wisconsin (sensu lato), and ca. 40 km during the late Wisconsin. Correlations with well-studied moraines in the southern Ahklun Mountains indicate an asymmetry of glaciation over the range, with ice-cap outlet glaciers more extensive to the south. This asymmetry was more striking during …

Type Locality For The Great Blue Limestone In The Bingham Nappe, Oquirrh Mountains, Utah, United States Geological Survey

All U.S. Government Documents (Utah Regional Depository)

The Great Blue Limestone was named originally by Spurr (1895) from exposures near the Mercur mining district in the Oquirrh Mountains, Utah. The formation was described in greater detail by Gilluly (1932) in the Ophir mining district. Neither formally established a type locality for this formation in the Oquirrh Mountains. However, the formation has since been correlated broadly with similar sedimentary rocks elsewhere in the adjoining Rocky Mountains and Great Basin regions. For the record, and to assist future correlations, a type measured section of the Great Blue Limestone in the Oquirrh Mountains is located, described, and a detailed measured …