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Mapping Of A Detachment Fault In Kythera Island And Study Of The Related Structural Shear Sense Indicators, Antonios Marsellos

Geology Theses and Dissertations

Kythera Island is located on the prominent submarine horst between Crete and the Peloponnese in the southwestern part of the Aegean. The structure of Kythera is characterized by a pile of tectonic slices derived from different paleogeographic zones. The upper unmetamorphosed units comprise pelagic limestones and cherts of Pindos zone emplaced by thrusting in the Eocene on top of Tripolis zone neritic limestones. These units are separated from the lower metamorphosed unit of Phyllite-Quartzite (PQU) exposed in the northern part of Kythera by an extensional detachment fault of Late Miocene age. The lower tectonic unit of PQU was affected by …

Spectral Analysis Of Ground Penetrating Radar Response To Thin Sedimentary Layers, Swagata Guha, Sarah E. Kruse, E. E. Wright, U. E. Kruse

Geology Faculty Publications

Ground penetrating radar (GPR) systems utilized in studies of sedimentary deposits generate wavelengths (tens of centimeters) that are commonly much longer than the thickness of bedding (often millimeters to centimeters) within the target strata. Where this is the case, radar profiles represent interference patterns. Simple models of radar response to sequences of thin beds such as those found in coastal deposits show potentially detectable spectral shifts toward higher frequencies in radar returns. Spectral analysis of radar data over barrier beach deposits at Waites Island, South Carolina, shows that returns from packages with heavy mineral laminations are shifted toward higher frequencies …

Relationship Between Fault Zone Architecture And Groundwater Compartmentalization In The East Tintic Mining District, Utah, Sandra Myrtle Conrad Hamaker

Theses and Dissertations

The Eureka Lilly fault zone provides an impermeable barrier for groundwater flow in the East Tintic mining district. The fault zone separates two distinct groundwaters that have different temperatures, compositions, and potentiometric surfaces. The damage zone of the fault is an extensive network of interconnected open fractures and fault intersections that provide conduits for groundwater flow in otherwise impermeable units. The fault core breccia has been re-cemented and mineralized, which eliminates porosity in the rock by creating a thick impermeable zone, which has compartmentalized groundwaters across the fault zone. The compartmentalization of groundwater shows that fault zone variability (from strain …

Geologic Map Of The Golden Throne Quadrangle, Wayne And Garfield Counties, Utah, Daniel H. Martin

Theses and Dissertations

The Golden Throne Quadrangle is located within Capitol Reef National Park, south-central Utah. Geologic mapping of this 1:24,000 scale 7.5 minute quadrangle began in 2003 as the National Parks Service desired to have geologic maps at this scale produced within the park. Stratigraphically, ten bedrock formations and ten Quaternary deposits are exposed within the Golden Throne Quadrangle. Geologic formations range in age from Permian to Jurassic. This map contains details not included on previous geologic maps including; the members of the Carmel, Chinle, and Moenkopi Formations. Additionally, the Page Sandstone is herein mapped as an independent unit. Structurally the Golden …

Effects Of Hurricane Fault Architecture On Groundwater Flow In The Timpoweap Canyon Of Southwestern, Utah, Sarah J. Dutson

Theses and Dissertations

Hydrogeologically important features of fault zones include undamaged country rock, the damage zone, and the core zone. Fault cores generally have low porosity and permeability, and often act as a barrier to groundwater flow. The damage zone, by contrast, consists of small faults and fracture networks, which can act as conduits. Timpoweap Canyon near Hurricane, Utah has superb exposures of the fault core and damage zone of the Hurricane Fault. Also within the canyon, springs discharge from the damage zone into the Virgin River, providing an ideal natural laboratory for the study of groundwater discharge from a fault zone. The …

Upper Mantle Reflectivity Beneath An Intracratonic Basin: Insights Into The Behavior Of The Mantle Beneath Illinois Basin., Maxwell Sunday Okure

Theses and Dissertations

Reflectivity images of the lower crust and uppermost mantle beneath the Illinois basin have been derived from reprocessing of several hundred kilometers of industry seismic reflection data using extended vibroseis recorrelation. The recorrelation was based on extending an originally 4-s correlated record, acquired with a 16-s sweep from 14 to 126 Hz, to the absolute limit of the full 20 s (~70 km) listening travel time. The reconstructed bandwidth includes frequency components suitable for imaging structures from signals received from both sedimentary basin reflectors and those received from reflectors in the deep crust and upper mantle. Mantle and sub-Moho reflectors …

A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau

Theses and Dissertations

Late Middle Eocene time marks one of the most dynamic periods of the Paleogene in the western interior of North America. Analysis of an extensive, new collection of plant, invertebrate, and vertebrae fossils from the Uinta Formation in the Uinta Basin, south of Myton, Utah, USA, provides evidence of environmental change. Paleobotanical specimens are preserved in late stage Uinta Lake sediments and coarse-grained fluvial sediments which are stratigraphically 650 to 660 m above the Green River Formation. Deposition rates estimates of 18 to 55 cm/kyr, for Uinta Lake sediments in the Uinta Basin suggest a period of 1.18 Ma to …

A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant

Theses and Dissertations

In addition to a loss of potential revenues from Utah's $393 million sport fishing industry, the state expends millions of dollars every year on costs associated with whirling disease mitigation and prevention. A state fish hatchery at Midway, Utah was closed when the shallow unconfined aquifer being used for fish culture by spring discharge was deemed to be contaminated by whirling disease. An alternative water source may exist in a confined aquifer below this contaminated unconfined aquifer. However, the complex hydrostratigraphy presents a challenge in determining if this source is a viable resource for fish culture. Geological, physical, chemical, geophysical, …

An Unusually Large Aulocopella Winnipegensis And Associated Demosponges From The Upper Ordovician Beaverfoot Formation, Southeastern British Columbia, J. Keith Rigby, Paul A. Johnston

Faculty Publications

An unusually large specimen of the rare digitate to bladed Aulocopella winnipegensis Rauff and three relatively normal sized specimens of ashtray-shaped Hudsonospongia? sp. constitute the first record of demosponges from the Upper Ordovician Beaverfoot Formation in southeastern British Columbia and the first record of these taxa from western Canada. Gross form and canal structure are well preserved, but dolomitization and (or) coarse microsphaeroidal silicification have obliterated spicules and other structural details. We interpret these sponges as epifaunal recliners, without means of attachment to the substrate, a life mode rarely encountered in the modern sponge biota.

The Cape Ann Plutonic Suite: A Field Trip For Petrology Classes, John B. Brady, John T. Cheney

Geosciences: Faculty Publications

Cape Ann, because of its proximity to Boston and many universities, has long been a focus of geologic study. Nineteenth century papers that consider mineralogy or petrology of Cape Ann rocks include Prescott (1839), Nichols (1856), Kimball (1860), Gregory (1862), Mudge (1862), Balch (1864), Cooke (1866, 1867), Knowlton (1867), Hyatt (1869, 1871a,b), Hunt (1871), Wadsworth (1878, 1882a,b, 1885), McDaniel (1884), Sears (1888, 1889, 1890a, 1891a,b, 1893a,b, 1894a,b, 1895, 1898), Shaler (1889), Pearce (1893), Penfield and Forbes (1896), and Washington (1898a,b,c, 1899a,b,c,d). More recent studies of note include Wright (1900), Clapp (1921), Warren and McKinstry (1924), Bowen and Schairer (1935), Palache …

40Ar/ 39Ar Ages Of Metamorphic Rocks From The Tobacco Root Mountains Region, Montana, John B. Brady, Dana N. Kovaric, John T. Cheney, Lisa J. Jacob, J. Toby King

Geosciences: Faculty Publications

Measurements of 60 single-grain, UV laser microprobe 40Ar/39Ar total gas ages for hornblende from metamorphic rocks of the Tobacco Root Mountains in southwest Montana yield a mean age of 1.71 ± 0.02 Ga. Measurements of 40Ar/39Ar step-heating plateau ages of three bulk hornblende samples from the Tobacco Root Mountains metamorphic rocks average 1.70 ± 0.02 Ga. We believe that these and the K/Ar or 40Ar/39Ar ages reported by previous workers are cooling ages from a 1.78 to 1.72 Ga, upper-amphibolite to granulite facies, regional metamorphism (Big Sky orogeny) that affected the northwestern portion of the Wyoming province, including the Tobacco …

Geogram 2003, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

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 …

Temporal Variation Of Seismic B-Values Beneath Northeastern Japan Island Arc, Aimin Cao, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Analysis of a high quality seismic catalog reveals that the average of seismic b-values in the crust beneath most part of northeastern Japan island arc decreased from 0.86 between 1984 and 1990, to 0.73 between 1991 and 1995. The two areas with the largest decrease are found to be in the same areas where the coupling between the North American and the Pacific plates is the highest, as suggested by a recent geodetic study. In the same time period, the annual seismic moment release increased by 10 times. In addition, there seems to be a corresponding increase in volcanic activities …

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 …

A New Occurrence Of Archaeoscyphia Pulchra (Bassler) From The Ordovician Of Western Canada, J. Keith Rigby, Godfrey S. Nowlan, Peter A. Rowlands

Faculty Publications

A few specimens of the ornate anthaspidellid demosponge, Archaeoscyphia pulchra (Bassler), have been collected from the Lower Ordovician Outram Formation or Skoki Formation, from a saddle at the head of South Rice Brook in northeastern British Columbia. This is the first report of the flanged-appearing annulate, steeply obconical sponge in western Canada, although it has been reported from the Mingan Islands of Quebec and was initially described from Nevada, in the western United States. The taxon has also been reported as other species of Archaeoscyphia from Ordovician rocks of Missouri and from the San Juan region of Argentina.

Lithospheric Structure Of The Basin And Range Province-Southwestern Colorado Plateau. Southeastern California, Southern Nevada, And Western Arizona, Nigel Oakley Hicks

Open Access Theses & Dissertations

The Basin and Range Province of the western United States is an unusually wide continental rift zone and its structure and evolution have been the topic of much debate. Active source seismic surveys within the Basin and Range Province have delineated a relatively uniform crustal thickness (-30 km) despite varying magnitudes of crustal extension (<10-300 km). Large scale Cenozoic crustal extension has exhumed midcrustal rocks (from 10-20 km depth) along low angle detachment faults to create metamorphic core complexes (exposed lower plate rocks). In contrast to the extreme amounts of extension and internal deformation of the Basin and Range, the Colorado Plateau has remained a relatively rigid block, with a crustal thickness of 40-50 km, apparently resistant to the deformation processes that have shaped the Basin and Range observed today. In general, geophysical surveys reveal a significant contrast in crustal structure between the Basin and Range and it's transition into the Colorado Plateau.

The debate about the origin of the Basin and Range has underscored the need for additional geophysical constraints. Thus in this study, a regional analysis of lithospheric structure in the region of southeastern California, southern Nevada, and western Arizona that includes the Basin and Rangesouthwestern …

Genesis And Evolution Of Proterozoic Crustal Boundaries In The Southern Rocky Mountains., Colin Arthur Shaw

Earth and Planetary Sciences ETDs

The lithosphere of the southwestern United States is a mosaic of Proterozoic arc terranes assembled to the southern margin of the Archean Wyoming craton between 1.8 and 1.6 Ga. This mosaic was profoundly transformed by ca. 1.4 Ga intracontinental plutonism, metamorphism, and tectonism. These processes of assembly and tectonic reactivation during the early stages of continental evolution laid the foundation for the development of the continental architecture of the southwestern United States.

This dissertation comprises three independent studies focused on different aspects of the Proterozoic evolution of tectonic boundaries exposed in the Southern Rocky Mountains. The first study is a …

Refined Kinematics Of The Eastern California Shear Zone From Gps Observations, 1993-1998, M. Meghan Miller, Timothy H. Dixon, Roy K. Dokka

All Faculty Scholarship for the College of the Sciences

Global Positioning System (GPS) results from networks spanning the Eastern California shear zone and adjacent Sierra Nevada block, occupied annually between 1993 and 1998, constrain plate margin kinematics. We use an elastic block model to relate GPS station velocities to long‐term fault slip rate estimates. The model accounts for elastic strain accumulation on the San Andreas fault, as well as faults of the Eastern California shear zone. South of the Garlock fault, 14 mm/yr of dextral shear is distributed across the Eastern California shear zone. Some of this slip penetrates eastward into the Basin and Range, and a collective budget …

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.

Magmatic Processes Operating During The Middle To Late Pliocene And Pleistocene Along The Transition Zone Near 43º North, Christy L. Lee

Dissertations and Theses

A geochemical and structural transition zone exists between the Cascades and Basin and Range provinces in Oregon. Geologic mapping in this area has allowed the definition of six volcanic rock sequences: 1) interfingered alkali-rich basaltic trachyandesite to trachydacite lava flows and low-alkali basaltic andesite lava flows, 2) HAOT lava flows, 3) basaltic andesite lava flows, 4) andesite lava flows and vent deposits with minor basaltic andesite lava flows, 5) HAB lava flows, and 6) interfingered basaltic andesite, andesite, and trachyandesite lava flows.

Geochemical models of sequence 1 alkali-rich rocks suggest the fractionation of the parent assemblage plag (An₅₅)+magn+ol±aug …

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 …

Carbonate Deposition And Sequence Stratigraphy Of The Terminal Cambrian Grand Cycle In The Southern Appalachians, U.S.A, Bosiljka Glumac, Kenneth R. Walker

Geosciences: Faculty Publications

The cessation of shale and carbonate deposition of the Conasauga Group grand cycles (Middle to Upper Cambrian) and the establishment of the widespread peritidal carbonate deposition of the Knox Group (Upper Cambrian to Lower Ordovician) represent a prominent change in sedimentation along the early Paleozoic passive continental margin in the southern Appalachians. To evaluate the causes for this change, this study focuses on the Maynardville Formation, which is the uppermost carbonate unit of the Conasauga Group. The Maynardville consists of: (1) a lower subtidal faciès succession, which is underlain by the Nolichucky Shale and resembles the rest of the Conasauga …

Geology Of The Oquirrh Mountains, Utah, United States Geological Survey

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

The Oquirrh Mountains are located in north-central Utah, immediately south of the Great Salt Lake, in the easternmost part of the Basin and Range physiographic province. The range consists of northerly-trending aligned peaks 56 kilometers long flanked on the west by Tooele and Rush Valleys and on the east by Jordan and Cedar Valleys. The range hosts several of the more prominent base- and precious-metal and desseminated-gold mining areas in the western United States. The 130-year old Bingham porphyry copper mining district, which is of world-class magnitude in the central part of the range, is still active. The Mercur mining …

Late Pleistocene Glacial Chronology Of The Western Ahklun Mountains, Southwestern Alaska, Jason P. Briner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

New glacial mapping and 35 cosmogenic ³⁶Cl surface exposure ages, the first ever reported from Alaska, constrain the extent and timing of late Pleistocene glacial fluctuations in the western Ahklun Mountains, southwestern Alaska. Morphometric and soil relative-age data characterize two main drift units deposited during the Arolik Lake and Klak Creek glaciations, named herein. During the Arolik Lake glaciation (early Wisconsin), outlet glaciers emanated from an ice cap over the central portion of the Ahklun Mountains and deposited moraines at or beyond the modern coast. These moraines have slope angles averaging about 11° and crests averaging about 35 m …

The Geomorphological History Of An Alluvial Fan Complex In Nelson County, Virginia, Melinda Ann Youngblood

OES Theses and Dissertations

An alluvial fan complex blankets a portion of the Rockfish Valley in Nelson County Virginia, located along the eastern slope of the Blue Ridge Mountains. The seven-km² field area contains three mappable relict alluvial surfaces (Qf1, Qf2, and Qf3) and one modern surface (Qa1), each of which is underlain by fluvial deposits dominated by greenstone and charnokite cobbles. The four surfaces were mapped according to topographic position and degree of stream dissection. Alluvial deposits underlying each surface were characterized using a 3-part clast weathering scale based on greenstone clast weathering rinds and using soil development criteria (clay content, Munsell …

An Evaluation Of Methods For Identifying And Interpreting Buried Soils In Late Quaternary Loess In Alaska, Daniel R. Muhs, Thomas A. Ager, Josh M. Been, Joseph G. Rosenbaum, Richard L. Reynolds

United States Geological Survey: Staff Publications

The presence of buried soils in Alaskan loess is controversial, and therefore criteria for identifying buried soils in these deposits need to be evaluated. In this paper, morphologic and chemical criteria for identifying buried soils are evaluated by studying modern soils developed mostly in Holocene loess under tundra, boreal forest, and transitional coastal-boreal forest vegetation in different parts of Alaska. Data from modern Alaskan soils that developed under vegetation similar to that of the present indicate that soil morphology, organic-matter concentrations, and P concentrations can be useful diagnostic tools for identifying buried soils. Soil morphologic criteria, particularly horizon colors and …

"Hades" - A Remarkable Cave On Oldoinyo Lengai In The East African Rift Valley, Gordon J. Davies

International Journal of Speleology

Oldoinyo Lengai is the world’s only active carbonatite volcano, situated in northern Tanzania within the Eastern Rift Valley, al 2.751 degrees S, 35.902 degrees E. It forms an isolated symmetrical cone at the southern end of Lake Natron, with a summit elevation of 2,890 m (9,480 ft). Periodic eruptions of ash and lava have been recorded since about 1880, and with increasing precision during this century since 1904. In 1990 a routine expedition to monitor activity levels at the summit led to the discovery of a remarkable cave located in the crater floor, filled with numerous long delicate pale yellow …