Geophysics and Seismology Commons^™

Bridging The Gap Between The Foreland And Hinterland I: Geochronology And Plate Tectonic Geometry Of Ordovician Magmatism And Terrane Accretion On The Laurentian Margin Of New England, Paul M. Karabinos, Francis A. Macdonald, James L. Crowley

Geosciences Faculty Publications and Presentations

U-Pb dates on magmatic and detrital zircon from samples in the hinterland of the Taconic orogen place new constraints on the timing and plate tectonic geometry of terrane accretion and magmatic arc activity. The Moretown terrane, a Gondwanan-derived exotic block, extends from the Rowe Schist-Moretown Formation contact in the west to the Bronson Hill arc in the east. Arc-related plutonic and volcanic rocks formed above an east-dipping subduction zone under the western leading edge of the Moretown terrane from approximately 500 to 475 Ma, until collision with hyperextended distal fragments of Laurentia, represented by the Rowe Schist, at 475 Ma. …

Spatio-Temporal History Of Fluid-Rock Interaction In The Hurricane Fault Zone, Jace Michael Koger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Hurricane Fault is a 250-km long, west dipping, active Basin and Range-bounding normal fault in southwest Utah and northwest Arizona. There are multiple known hot springs along its 250-km length and multiple late Tertiary-Quaternary basaltic centers that broadly parallel the fault. Possible sources of hot spring fluids include deeply circulated meteoric water that experienced water-rock exchange at high temperatures (>100 °C) and deep-seated crustal fluids. Abundant damage zone veins, cements, and host rock alteration are present along strike, indicative of past fluid flow. Carbonate veins and cements are key features of the Hurricane Fault zone, and the primary …

Lithospheric Evaluation Of The Mid-Continental Rift System In Iowa From A Gravity And Magnetic Analysis, Moamen Mohamed Almaz

Graduate Theses/Dissertations

The Proterozoic Midcontinent Rift System (MCRS) is considered one of the most important tectonic features in North America and was formed during a continental breakup event at 1.1 Ga (billion years). The MCRS is totally covered by Phanerozoic sedimentary rocks except in the Lake Superior region. Consequently, the geological characteristics of the MCRS are primarily inferred from extrapolations from the outcrop areas, drill holes, and from a variety of geophysical investigations. Iowa has a large segment of the MCRS which to date has only been partially investigated geophysically with little information regarding the lower crustal and upper mantle structure under …

Classifying Microseismicty At Mount St. Helens Using A Large-N Array, Margaret E. Glasgow

Earth and Planetary Sciences ETDs

A dense array of ~1,000 continuously recording, short-period geophones was deployed in the summer of 2014 within ~15 km of Mount St. Helens. Two earthquake catalogs created using reverse time imaging and template detection techniques, increase the detection rate and completeness of the earthquake catalog when compared to the permanent network, Pacific Northwest Seismic Network, catalog. An investigation into event type for ~200 of the earthquake detections leads to the discrimination of two major classification groups, volcano-tectonic and long period. Previous to this study, long period earthquakes had not been identified in the upper crust during a volcanically inactive period …

Inference Of Soil Hydrologic Parameters From Electronic Soil Moisture Records, David G. Chandler, Mark S. Seyfried, James P. Mcnamara, Kyotaek Hwang

Geosciences Faculty Publications and Presentations

Soil moisture is an important control on hydrologic function, as it governs vertical fluxes from and to the atmosphere, groundwater recharge, and lateral fluxes through the soil. Historically, the traditional model parameters of saturation, field capacity, and permanent wilting point have been determined by laboratory methods. This approach is challenged by issues of scale, boundary conditions, and soil disturbance. We develop and compare four methods to determine values of field saturation, field capacity, plant extraction limit (PEL), and initiation of plant water stress from long term in-situ monitoring records of TDR-measured volumetric water content (Θ). The monitoring sites represent a …

Quantitative River Profile Analysis To Investigate Exhumation Of The Siwalik Foreland Basin, Nepalese Himalaya, Indu Bhattarai

Masters Theses & Specialist Projects

The Nepalese Himalaya, one of the most active regions within the Himalayan Mountain belt, is characterized by a thick succession of Miocene age Siwalik sedimentary rocks deposited at its foreland basin. To date, much of its tectonic evolution, including exhumation in the Nepalese Siwalik, is poorly understood. This study of a quantitative analysis of the bedrock river parameters should provide crucial information regarding tectonic activities in the area. The study investigated geomorphic parameters of river longitudinal profiles from 54 watersheds within the Siwalik section of the Nepalese Himalaya, for the first time. A total of 140 bedrock rivers from these …

Assessing Seasonal And Spatial Variability In The Hydrogeochemistry Of Glacial Meltwater In Iceland, Anisha Tuladhar

Masters Theses & Specialist Projects

A detailed comparative geochemical characterization of three different types of Iceland glacial systems was conducted during June, August, and October, 2016. The study was carried out at a total of 11 outlet glacier rivers flowing from the icecaps Vatnajökull, Eyjafjallajökull, and Mýrdalsjökull. A total of 75 grab samples were collected (25 for each sampling period). The hydrogeochemical variations of Icelandic glacial meltwater are influenced by volcanic activity, temporal changes, and geographical location, which differed between the sampling sites within the glaciers and icecaps. Lower pH range, and comparatively higher and variable specific conductivity, SO4, S and F is linked to …

Synoptic Atmospheric Conditions, Land Cover, And Equivalent Temperature Variations In Kentucky, Dorothy Yemaa Na-Yemeh

Masters Theses & Specialist Projects

Research has demonstrated that equivalent temperature (T_E), which incorporates both the surface air temperature (T) and moist heat content associated with atmospheric moisture, is a better indicator of overall heat content. This thesis follows up on a study that used T_E to determine the impacts of land use/land cover and air masses on the atmospheric heat content over Kentucky during the growing season (April-September). The study, which used data from the Kentucky Mesonet, reveals that moist weather types dominate the growing season and, as expected, differences between T and T_E are smaller under dry atmospheric conditions …

Controls On Fracture Network Characteristics Of The Middle Member Of The Bakken Formation, Elm Coulee Field, Williston Basin, Usa, Shashank Khatri

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Bakken formation in the Elm Coulee Field of the Williston Basin consists of three members: 1) upper shale member, 2) middle silty dolostone member, and 3) lower shale member. The upper and lower members act as excellent source rocks and the main reservoir is the middle member with an average porosity of 3 to 9% and average permeability of 0.04md. The Bakken oil play in this area is a stratigraphic trap with a pinch-out to the southwest and a diagenetic facies change in the northeast. The main production is interpreted to come from matrix permeability in the field area. …

Gravity And Passive Seismic Methods Used Jointly For Understanding The Subsurface In A Glaciated Terrain: Dowling And Maple Grove Quadrangles, Barry County, Michigan, Scott A. Feldpausch

Masters Theses

The Horizontal to Vertical Spectral Ratio (HVSR) passive, single sensor seismic technique has been used together with gravimetry to study the topography hidden below the glacial drift of two 7.5’ quadrangles in Barry Co., MI. 265 stations were observed with both instruments along roads at nominal spacings of about 0.4 to 0.8 km. Occasional water wells and oil wells with documented penetrations of the base of glacial were used to calibrate the local power law regression calibration. This was also compared with the statewide calibration curve previously established. Results are presented as maps of Simple Bouguer Anomaly, Residual Bouguer Anomaly, …

3d Cave And Ice Block Morphology From Integrated Geophysical Methods: A Case Study At Scărişoara Ice Cave, Romania, Jackson Durain Hubbard

USF Tampa Graduate Theses and Dissertations

Scărişoara Ice Cave has been a catalyst of scientific intrigue and effort for over 150 years. These efforts have revealed and described countless natural phenomena – and in the process have made it one of the most studied caves in the world.

Of especial interest is the massive ice block located within its Great Hall and scientific reservations. The ice block, which is the oldest and largest known to exist in a cave, has been the focus of multiple surveying and mapping efforts, typically ones utilizing traditional equipment. In this study, the goals were to reconstruct the ice block/cave floor …

Regional Greenland Accumulation Variability From Operation Icebridge Airborne Accumulation Radar, Gabriel Lewis, Erich Osterberg, Robert Hawley, Brian Whitmore, Hans Peter Marshall, Jason Box

CGISS Publications and Presentations

The mass balance of the Greenland Ice Sheet (GrIS) in a warming climate is of critical interest to scientists and the general public in the context of future sea-level rise. An improved understanding of temporal and spatial variability of snow accumulation will reduce uncertainties in GrIS mass balance models and improve projections of Greenland's contribution to sea-level rise, currently estimated at 0.089 ± 0.03 m by 2100. Here we analyze 25 NASA Operation IceBridge accumulation radar flights totaling > 17 700 km from 2013 to 2014 to determine snow accumulation in the GrIS dry snow and percolation zones over the past …

Evidence Of Erosional Self-Channelization Of Pyroclastic Density Currents Revealed By Ground-Penetrating Radar Imaging At Mount St. Helens, Washington (Usa), Andrew C. Gase, Brittany D. Brand, John H. Bradford

Geosciences Faculty Publications and Presentations

The causes and effects of erosion are among the least understood aspects of pyroclastic density current (PDC) dynamics. Evidence is especially limited for erosional self-channelization, a process whereby PDCs erode a channel that confines the body of the eroding flow or subsequent flows. We use ground-penetrating radar imaging to trace a large PDC scour and fill from outcrop to its point of inception and discover a second, larger PDC scour and fill. The scours are among the largest PDC erosional features on record, at >200 m wide and at least 500 m long; estimated eroded volumes are on the order …

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 …

Ground-Rupturing Earthquakes On The Northern Big Bend Of The San Andreas Fault, California, 800 A.D. To Present, Katherine Scharer, Ray J. Weldon Ii, Glenn Biasi, Ashley Streig, Thomas Fumal

Geology Faculty Publications and Presentations

Paleoseismic data on the timing of ground-rupturing earthquakes constrain the recurrence behavior of active faults and can provide insight on the rupture history of a fault if earthquakes dated at neighboring sites overlap in age and are considered correlative. This study presents the evidence and ages for 11 earthquakes that occurred along the Big Bend section of the southern San Andreas Fault at the Frazier Mountain paleoseismic site. The most recent earthquake to rupture the site was the Mw7.7–7.9 Fort Tejon earthquake of 1857. We use over 30 trench excavations to document the structural and sedimentological evolution of a small …

Contributions Of Wood Smoke And Vehicle Emissions To Ambient Concentrations Of Volatile Organic Compounds And Particulate Matter During The Yakima Wintertime Nitrate Study, Graham Vanderschelden, Benjamin De Foy, Courtney Herring, Susan D. Kaspari, Tim Vanreken, Bertram Jobson

All Faculty Scholarship for the College of the Sciences

A multiple linear regression (MLR) chemical mass balance model was applied to data collected during an air quality field experiment in Yakima, WA, during January 2013 to determine the relative contribution of residential wood combustion (RWC) and vehicle emissions to ambient pollutant levels. Acetonitrile was used as a chemical tracer for wood burning and nitrogen oxides (NOx) as a chemical tracer for mobile sources. RWC was found to be a substantial source of gas phase air toxics in wintertime. The MLR model found RWC primarily responsible for emissions of formaldehyde (73%), acetaldehyde (69%), and black carbon (55%) and mobile sources …

Probabilistic Inversion With Graph Cuts: Application To The Boise Hydrogeophysical Research Site, Guillaume Pirot, Niklas Linde, Grégoire Mariethoz, John H. Bradford

CGISS Publications and Presentations

Inversion methods that build on multiple-point statistics tools offer the possibility to obtain model realizations that are not only in agreement with field data, but also with conceptual geological models that are represented by training images. A recent inversion approach based on patch-based geostatistical resimulation using graph cuts outperforms state-of-the-art multiple-point statistics methods when applied to synthetic inversion examples featuring continuous and discontinuous property fields. Applications of multiple-point statistics tools to field data are challenging due to inevitable discrepancies between actual subsurface structure and the assumptions made in deriving the training image. We introduce several amendments to the original graph …

Household Preparedness Motivation In Lahar Hazard Zones: Assessing The Adoption Of Preparedness Behaviors Among Laypeople And Response Professionals In Communities Downstream From Mount Baker And Glacier Peak (Usa) Volcanoes, Kimberley A. Corwin, Brittany D. Brand, Monica L. Hubbard, David M. Johnston

Geosciences Faculty Publications and Presentations

As the number of people living at risk from volcanic hazards in the U.S. Pacific Northwest grows, more detailed studies of household preparedness in at-risk communities are needed to develop effective mitigation, response, and recovery plans. This study examines two aspects of preparedness behavior motivation in the Skagit Valley (WA), which is at risk from Mount Baker and Glacier Peak lahars. First, we examine the influence of perceived response-efficacy, protective response costs, self-efficacy, and ascription of responsibility on preparedness. Results indicate few respondents believe high perceived protective response costs, low perceived response-efficacy, or low perceived protection responsibility prevent them from …

Delineation Of Karst Geohazards Along Rm 652 Through The Use Of Ground Penetrating Radar: Culberson County, Texas, Aaron A. Eaves

Electronic Theses and Dissertations

The Delaware Basin is the western member of the larger Permian Basin, and is located in the Trans-Pecos region of Texas and New Mexico. The Delaware Basin hosts significant evaporite karst geohazards throughout the Gypsum Plain of the Castile Formation, where geohazards of all scales form beneath and immediately adjacent to major infrastructure throughout the region, especially Ranch-to-Market 652, including geohazards ranging from small scale dissolution of road base, to large scale cave and sinkhole development. Gypsum sourced from the Castile and Rustler formations was used to create the road base of this RM652 , which meteoric waters have easily …

Dependence Of The Martian Radiation Environment On Atmospheric Depth: Modeling And Measurement, Jingnan Guo, Tony C. Slaba, Cary Zeitlin, Robert F. Wimmer-Schweingruber, Francis F. Badavi, Eckart Böhm, Stephan Böttcher, David E. Brinza, Bent Ehresmann, Donald M. Hassler

Physics Faculty Publications

The energetic particle environment on the Martian surface is influenced by solar and heliospheric modulation and changes in the local atmospheric pressure (or column depth). The Radiation Assessment Detector (RAD) on board the Mars Science Laboratory rover Curiosity on the surface of Mars has been measuring this effect for over four Earth years (about two Martian years). The anticorrelation between the recorded surface Galactic Cosmic Ray-induced dose rates and pressure changes has been investigated by Rafkin et al. (2014) and the long-term solar modulation has also been empirically analyzed and modeled by Guo et al. (2015). This paper employs the …