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Geology

All Master's Theses

Theses/Dissertations

2015

Articles 1 - 8 of 8

Full-Text Articles in Physical Sciences and Mathematics

Geologic Mapping In The Black Mountain Area, Northern Eastern California Shear Zone: Testing A Kinematic And Geometric Fault Slip Transfer Model, Kevin M. Delano Jan 2015

Geologic Mapping In The Black Mountain Area, Northern Eastern California Shear Zone: Testing A Kinematic And Geometric Fault Slip Transfer Model, Kevin M. Delano

All Master's Theses

New geologic mapping, structural, kinematic, and 40Ar/39Ar geochronology studies in the Black Mountain area, northern eastern California shear zone, are used to test a kinematic fault slip transfer model for the Owens Valley fault-Mina deflection transition. In the Black Mountain area, range bounding ~NNW- to ~NS-striking and lesser NW- to NE-striking normal faults cut Mesozoic, Miocene (22.42 ± 0.05 Ma), Pliocene (3.53 ± 0.06 to 3.29 ± 0.02 Ma), and early-middle Pleistocene (1936 ± 12.7 to 766 ± 3.1 ka) rocks. Palinspastically restored cross-sections show that offset Pliocene markers record 1.5 +0.7/-0.6 km of ~ENE-WSW extension since …

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Timing And Source Of Alkali Enrichment At Mt. Etna, Sicily: Constraints From Clinopyroxene Geobarometry And In Situ Sr Isotope Data, Kaitlyn Nelson Jan 2015

Timing And Source Of Alkali Enrichment At Mt. Etna, Sicily: Constraints From Clinopyroxene Geobarometry And In Situ Sr Isotope Data, Kaitlyn Nelson

All Master's Theses

Since 1971, Mt. Etna, Europe’s largest and most active volcano, has exhibited increased eruption frequency and explosivity. Associated with this increased activity, researchers have documented higher abundances of alkali elements (K, Rb, Cs) as well as elevated 87Sr/86Sr in Etnean lavas. The source of this alkali-enrichment has been hotly debated, with end-member hypotheses involving mantle vs. crustal contributions. To further characterize the evolution of the subvolcanic magma storage and transport system, as well as the timing and source of alkali-enrichment, clinopyroxene from ten samples erupted between 1329 and 2004 was targeted for in situ textural, major element …

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Using Particle Size Analysis To Separate The Deposition Of A Bonebed And Artifact At The Wenas Creek Mammoth Site, Genevieve Brown Jan 2015

Using Particle Size Analysis To Separate The Deposition Of A Bonebed And Artifact At The Wenas Creek Mammoth Site, Genevieve Brown

All Master's Theses

The 2005 discovery of a 17,000 year old mammoth bonebed in close proximity to a possible artifact at the Wenas Creek Mammoth Site (WCMS) brought with it the question of whether the bones and artifact were actually deposited together. If the two are associated, the WCMS would qualify as a Pre-Clovis site, a title given to just a handful of proven archaeological sites in North America, though claimed for numerous more. A close interval particle size analysis was performed on 2 column samples from the WCMS with the intention of identifying microstratification that would separate the bonebed from the artifact. …

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Using Modflow To Predict Impacts Of Groundwater Pumpage To Instream Flow: Upper Kittitas County, Washington, Zoe O. Futornick Jan 2015

Using Modflow To Predict Impacts Of Groundwater Pumpage To Instream Flow: Upper Kittitas County, Washington, Zoe O. Futornick

All Master's Theses

Surface waters in the Yakima River Basin in central Washington are considered over allocated. Since 1960, new water demands have been met through groundwater withdrawals, with most groundwater users holding a later priority date than senior and junior surface water users. As a result of the discussions surrounding this issue, the Upper Kittitas Groundwater Rule has been in effect since 2010. Pumping from new domestic (i.e., permit-exempt or “exempt”) groundwater wells in Upper Kittitas County is not allowed unless mitigation is used to offset the groundwater use. The United States Geological Survey (USGS) has already created a basin-wide model for …

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Quantifying Channel Responses To The Removal Of The Glines Canyon Dam In The Middle Reach Of The Elwha River, Washington, Bryon J. Free Jan 2015

Quantifying Channel Responses To The Removal Of The Glines Canyon Dam In The Middle Reach Of The Elwha River, Washington, Bryon J. Free

All Master's Theses

Four different study sites throughout the middle reach of the Elwha River were monitored before, during, and after the dam removal process over a period of two years from 2012-2014. The complexity of the river geometry was a major factor in the ability of the river to trap and accumulate the new influx of woody debris and sediment from the dam removal, which influenced the response of the river channel. The change that occurred was quantified by using repeat Terrestrial LiDAR (TLS), sediment distribution surveys, and large woody debris mapping techniques. The morphologic changes that occurred during this time were …

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Pressure-Temperature-Time Constraints For Exhumation Of Ultrahigh-Pressure Metamorphic Rocks, North Qaidam Terrane, Western China, Brittany Kristine Fagin Jan 2015

Pressure-Temperature-Time Constraints For Exhumation Of Ultrahigh-Pressure Metamorphic Rocks, North Qaidam Terrane, Western China, Brittany Kristine Fagin

All Master's Theses

Ultrahigh-pressure rocks of a Paleozoic continental suture zone are exposed in the southeastern North Qaidam terrane (Dulan region). Garnetite sample D119 contains minor Czo+Qtz+Chl+Ttn; rutile inclusions in titanite suggest that titanite replaced rutile during decompression. Pressure-temperature estimates of sample D119 are 16.1-18.4 kbar and 485-520 °C. Sample D130B is a mafic band in calc-silicate gneiss, with garnet porphyroblasts in a fine-grained Hbl-Cpx-Pl-Qtz symplectite that is interpreted as former omphacite. D130B symplectite pressure-temperature estimates are 7.7-9.4 kbar and 623-708 °C. Titanite U-Pb ages of 419.7±3.1 Ma and 415.9±4.2 Ma are interpreted to date retrogression of D119 and D130B, respectively. Average exhumation …

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Field Observations And Modeling Of The 1957 Earthquake And Tsunami On The Islands Of The Four Mountains, Aleutian Islands, Alaska, Frances R. Griswold Jan 2015

Field Observations And Modeling Of The 1957 Earthquake And Tsunami On The Islands Of The Four Mountains, Aleutian Islands, Alaska, Frances R. Griswold

All Master's Theses

Due to a lack of research in the Aleutian Islands, a comprehensive history of the Aleutian subduction zone is not developed; however, this study indicates that the Aleutian subduction zone is capable of generating magnitude ~9 earthquakes or larger in addition to trans-Pacific tsunamis. Comparison of simulated runup and observed runup will help to determine the characteristics of rupture in the eastern Aleutians. A recent survey of the tsunami wrackline produced by the 1957 Great Aleutian earthquake (Mw 8.6) indicates runup up to 17.5 m in the Islands of the Four Mountains (presented here). Combined with other nearfield observations …

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Rapid Middle To Late Miocene Slip Along The Zanskar Normal Fault, Greater Himalayan Range, Nw, India: Constraints From Low-Temperature Thermochronometry, Brett L. Shurtleff Jan 2015

Rapid Middle To Late Miocene Slip Along The Zanskar Normal Fault, Greater Himalayan Range, Nw, India: Constraints From Low-Temperature Thermochronometry, Brett L. Shurtleff

All Master's Theses

The Zanskar normal fault (ZF) is a NW-striking, moderately NE-dipping, normal fault that bounds the northern flank of the Greater Himalaya Range, NW India. The ZF is the far west continuation of the South Tibetan Detachment System (STDS), a major arc-parallel normal sense shear zone that spans the length of the Himalayan orogen. Detailed new zircon and apatite (U-Th)/He (ZHe and AHe) and apatite fission-track (AFT) thermochronometric data from high-grade (amphibolite-migmatite) Greater Himalayan Sequence (GHS) metamorphic rocks, exposed in the footwall immediately adjacent to the ZF, provide constraints on the middle Miocene to present exhumation history of the footwall. The …

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