Tectonics and Structure Commons^™

Middle Miocene To Holocene History Of The Delacroix Island Fault System, Jarrett Leigh Levesh

LSU New Orleans Theses and Dissertations

An in-depth field study of the Delacroix Island producing field illustrates the evolution of the east-trending Delacroix Island Fault during the last 13 My. Well log correlations and 3-D seismic interpretation of 22 subsurface bio-stratigraphic horizons across the fault reveal variable stratigraphic thicknesses and displacement. Wells, with well log curve data as shallow as 31 m (100 ft) below the surface, were used to calculate interval thicknesses, expansion indices, sediment accumulation rates, burial history and magnitudes of displacement. Through these analyses, a correlation was found between the positioning of ancient Miocene depocenters over Delacroix Island and a period of increased …

A Record Of The Precambrian-Cambrian Transition In Sw Montana: A Late Neoproterozoic To Early Cambrian Stratigraphic Window, Fortunian Biostratigraphic Assemblage And Treptichnus Pedum, R. Reid Trippe

Graduate Student Theses, Dissertations, & Professional Papers

This study documents a Late Neoproterozoic through Early Cambrian stratigraphic record in the Humbolt anticline of southwestern Montana. The Precambrian-Cambrian transition includes a Fortunian-aged biostratigraphic trace-fossil assemblage with the ichnofossil Treptichnus pedum. The Humbolt anticline represents an inverted paleo-graben that exposes a stratigraphic window interpreted to be a record of rifting along the Cordilleran miogeoclinal margin, linked with the breakup of the Rodinia supercontinent. The graben subsided and captured sediment during late-stage rifting and final-stage dissociation along the rift margin. Its structural axis paralleled the rift margin. Sevier/Laramide orogenic thrusting inverted the graben into the Humbolt anticline. The Late …

Late Devonian Sedimentary Record Of Appalachian Tectonics And Erosion: Geochronology And Geochemistry Of Detrital Muscovite And Zircon From Central Pennsylvania Strata, Cole T. Gardner

Honors Theses

Foreland basin sediment deposition in North-Central Pennsylvania during Late Devonian time records erosion of hinterland source terranes exhumed during regional plate convergence, including the collisional Acadian orogeny. The Catskill clastic wedge preserves a coarsening-upwards stratigraphic succession from marine to fluvial environments associated with sediment progradation and sea-level regression, yet depositional timescales and quantitative provenance data are largely unconstrained.

Detailed facies analysis of eight outcrops spanning >2 km of stratigraphy in Lycoming Co., Pennsylvania documents distinct upsection changes, interpreted to reflect changes in depositional environments consistent with previous sedimentology of the Catskill clastic wedge. Stratigraphy displays a transition from nearshore marine …

Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Arctic Alaska–Chukotka microplate is a large Mesozoic–Cenozoic composite terrane that resides at the northern limit of the North American Cordillera. Although its Mesozoic origins are assuredly linked to the opening of the Amerasian Basin of the Arctic Ocean, its Paleozoic origins can be linked to at least three separate paleocontinents, including northern Laurentia, Baltica, and Siberia. Across the Arctic Alaska portion of the microplate, an internal, mid-Paleozoic suture zone presumably separates rocks of the North Slope subterrane (Laurentian affinity) from a collection of smaller subterranes in the southern Brooks Range and Seward Peninsula (Baltic affinity).

The mountains of the …

An Analysis Of Fractures Around The Sevier Fault Zone Near Orderville, Utah, Charley H. Hankla

Senior Independent Study Theses

Structural discontinuities—such as opening mode joints, shear fractures, and faults— tend to occur in close geographic proximity to one another; however, the timing relationships between these structures is not always easy to discern in the field. In southwestern Utah, the Jurassic Navajo Sandstone is cut by large-scale normal faults associated with the Sevier Fault Zone, making it perfect for observing several fracture types. The aim of this study is to complete a dynamic and kinematic analyses of the fractures near a major fault and to determine the chronologic relationships between the fractures. Specifically, we observed a previously unnamed segment of …

40ar/39ar Ages And Zircon Petrochronology For The Rear Arc Of The Izu-Bonin-Marianas Intra-Oceanic Subduction Zone, Graham Dm Andrews

Faculty & Staff Scholarship

Long-lived intra-oceanic arcs of Izu-Bonin-Marianas (IBM)-type are built on thick, granodioritic crust formed in the absence of pre-existing continental crust. International Ocean Discovery Program Expedition 350, Site U1437, explored the IBM rear arc to better understand continental crust formation in arcs. Detailed petrochronological (U–Pb geochronology combined with trace elements, oxygen and hafnium isotopes) characterizations of zircon from Site U1437 were carried out, taking care to exclude potential contaminants by (1) comparison of zircon ages with ship-board palaeomagnetic and biostratigraphic ages and 40Ar/39Ar geochronology, (2) analysing zircon from drill muds for comparison, (3) selectively carrying out in situ analysis in petrographic …

Structural And Stratigraphic Reconstruction Of The Whiting Dome Salt Structure In Viosca Knoll-Mississippi Canyon, Gom, Using 3d Seismic Data, Matthew R. Worrell

Electronic Theses and Dissertations

Understanding the complexities of salt tectonics is one of the most important factors regarding seismic interpretation of stratigraphy, structure, and geomorphology in the Gulf of Mexico. Evaluating the processes affecting recent mobilization of salt in the shallow, well-imaged section can help provide analogues for older, similar occurrences in the deeper section, thereby providing structural models for the autochthonous salt and its effect on stratigraphy and even potential timing and migration issues of hydrocarbons.

Progradation of delta front and shelf to slope transitional sediments has expulsed and emplaced an allochthonous salt structure (Whiting Dome) in the Viosca Knoll and Mississippi Canyon …

The Tuscaloosa Marine Shale: Geologic History, Depositional Analysis, And Exploration Potential, Jessica D. Pair

Electronic Theses and Dissertations

The Tuscaloosa Marine Shale (TMS) was deposited across southern Louisiana and Mississippi during the Upper Cretaceous. The study focuses on a core region containing vast deposits of Cretaceous-aged sediments that have economic importance for oil and gas exploration. This region has been conventionally drilled for decades, focusing on the recovery of the Cretaceous hydrocarbons. Explorers within this region had traditionally targeted the massive sand units of the Lower and Upper Tuscaloosa Group while neglecting the middle Tuscaloosa Marine Shale unit. With the onset of unconventional drilling technology, new explorers to the region have begun to delineate the Tuscaloosa Marine Shale’s …

The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu

Department of Earth and Atmospheric Sciences: Faculty Publications

The reactivation potential of pre-existing deep-seated structures influences deformation structures produced in subsequent compression. This contribution investigates thrust geometries produced in surface thrust sheets of the Sawtooth Range, Montana, USA, deforming over a previously faulted sedimentary section. Surface thrust fault patterns were picked using existing maps and remote sensing. Thrust location and regional transport direction was also verified in the field. These observations were used to design a series of analogue models, involving deformation of a brittle cover sequence over a lower section with varying numbers of vertical faults. A final model tested the effect of decoupling the upper cover …

High-Frequency Tectonic Sequences In The Campanian Castlegate Formation During A Transition From The Sevier To Laramide Orogeny, Utah, U.S.A., David B. Cross

LSU New Orleans Theses and Dissertations

Though stratigraphic correlations are abundant in the Cordilleran basin-fill, they rarely include along-strike transects providing a spatio-temporal sense of deformation, sediment-supply and subsidence. A new, high-resolution, regional strike-correlation of the Castlegate Formation reveals progressive northward-growth of the San Rafael Swell during two embryonic episodes of Laramide-style deformation in central Utah. The intrabasinal deformation-events produced gentle lithospheric-folding punctuated by erosional-truncation of upwarped regions. The earliest episode occurred at 78 Ma in the southern San Rafael Swell likely causing soft-sediment deformation and stratal-tilting. Following this the alluvial-plain was leveled and rapid, extensive-progradation took place. A second episode, at 75 Ma, where deformation …

Paleoearthquakes Of The Past ~6000 Years At The Dead Mouse Site, West-Central Denali Fault At The Nenana River, Alaska, Joseph K. Carlson

Theses and Dissertations--Earth and Environmental Sciences

The Denali fault (DF) in south-central Alaska is a major right lateral strike-slip fault that parallels the Alaska Range for much of its length. This fault represents the largest seismogenic source for interior Alaska but due to its remote location and difficulty of access, a dearth of paleoearthquake (PEQ) information exists for this important feature. The fault system is over 1200 km in length and identification of paleoseismic sites that preserve more that 2-3 PEQs has proven challenging. In 2012 and 2015, we developed the ‘Dead Mouse’ site, which provides the first long PEQ record west of the 2002 rupture …

Hazard Identification And Coastal Stratigraphy In Crescent Harbor, Northeast Whidbey Island, Washington, Brian Ostrom

All Master's Theses

Crescent Harbor marsh, on northeastern Whidbey Island, records evidence of co-seismic land-level change 1825 to 1925 cal. yrs. BP. The lithostratigraphy and diatom microfossil assemblages reveal a marsh peat abruptly overlain by intertidal mud, indicating rapid subsidence. Analysis of the modern-day position of depositional facies indicates subsidence from a high marsh to a tidal-flat environment representing an estimated 1.7 m elevation change. The timing of subsidence fits within the dates of a rupture found on the nearby Utsalady Point fault between 1,100 and 2,200 years BP (Johnson et al. 2004). Likely, the stratigraphy at Crescent Harbor records the same event …

A College Level Geology Field Trip In Western Connecticut And Vicinity, Stanley Schleifer, Nazrul I. Khandaker, Keshaw Narine, Ezazul Haque, Ratan Dhar

Publications and Research

There are a number of excellent locations for field exposure for college students in, and around Western Connecticut. These are accessible for a one day field trip within striking distance of New York City, Bridgeport and New Haven, CT and other nearby locations. They are also suitable for an expanded weekend field trip. The field locations include; Kent Falls State Park, Kent, CT, Dinosaur State Park, Rocky Hill, CT, the Hubbard Mining Museum, Kent, CT, Bash Bish Falls in Mt. Washington, Massachusetts, Macedonia Brook State Park in Kent, CT and various outcrops exposed along U. S. Route 7 north of …

Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou

Department of Earth, Environment and Sustainability Faculty Publications

In the Asian monsoon region, variations in the stable isotopic composition of speleothems have often been attributed to the "amount effect". However, an increasing number of studies suggest that the "amount effect" in local precipitation is insignificant or even non-existent. To explore this issue further, we examined the variability of daily stable isotopic composition (δ18O) in precipitation from September 2011 to November 2014 in Nanjing, eastern China. We found that intra-seasonal variations of δ18O during summer were not significantly correlated with local rainfall amount but could be linked to changes in the moisture source location and rainout processes in the …

Geologic Map Of The Welcome Quadrangle And An Adjacent Part Of The Wells Quadrangle, Elko County, Nevada, Allen J. Mcgrew, Arthur W. Snoke

Department of Earth, Environment and Sustainability Faculty Publications

Located in central Elko County, the Welcome and adjacent part of the Wells quadrangles expose a remarkable array of critical relationships for understanding the geologic history of the State of Nevada and the interior of the southwestern U.S. Cordillera. Covering the northern end of the East Humboldt Range and adjacent Clover Valley and Clover Hill, this map includes the northern terminus of the Ruby Mountains-East Humboldt Range metamorphic core complex. The oldest rocks in the State of Nevada (the gneiss complex of Angel Lake), and Nevada’s only exposures of Archean rock, form the core of a multikilometer scale, southward-closing recumbent …

Combining Quantitative Eye-Tracking And Gis Techniques With Qualitative Research Methods To Evaluate The Effectiveness Of 2d And Static, 3d Karst Visualizations: Seeing Through The Complexities Of Karst Environments, Elizabeth Katharyn Tyrie

Masters Theses & Specialist Projects

Karst environments are interconnected landscapes vulnerable to degradation. Many instances of anthropogenic karst disturbance are unintentional, and occur because of the public's lack of understanding or exposure to karst knowledge. When attempts are made to educate the general public about these landscapes, the concepts taught are often too abstract to be fully understood. Thus, karst educational pursuits must use only the most efficient and effective learning materials. A technique useful for assessing educational effectiveness of learning materials is eye-tracking, which allows scientists to quantitatively measure an individual's points of interest and eye movements when viewing a 2D or 3D visualization. …

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Department of Earth, Environment and Sustainability Faculty Publications

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …

An Apparent Angular Unconformity In Western Connecticut, Stanley Schleifer, Nazrul I. Khandaker, Adisa Charles, Hernando Martinez, Shirley Jackson, Chiemeka Ihebom

Publications and Research

The recent extension, to the north, of the U. S. Route 7 ‘superhighway’ in the town of Brookfield, Connecticut has involved the excavation of crystalline bedrock of lower Paleozoic to upper Proterozoic age in the area. The road cuts produced by this excavation have exposed some interesting features of structure and lithology. An outcrop, observed by the authors off the east side of route 7, at grid coordinates 41.482444 N, 73.415307 W is of particular interest. It appears, to the casual observer to be an angular unconformity. Maps and publications regarding this area of Western Connecticut support the likelihood of …

Tectonosedimentologic Significance Of The Upper Cretaceous Foreland Basin Siliciclastics: Western Interior, Usa, Nazrul I. Khandaker

Publications and Research

The Upper Cretaceous Frontier Formation exposed along the western margin of the western interior foreland basin is composed of clastic sediments that were deposited during the initial late Cretaceous transgressive-regressive phases of the Western Interior Seaway across Wyoming (Figure 1). Current study is aimed at providing attendees with the best practices associated with tectonic, lithofacies and sedimentologic interpretation of foreland basin sequences and emphasizing the need for utilizing field, structural, geochemical, and compositional data for reconstructing a viable scenario connected with foreland basin sedimentary packages. An attempt will be made to compare documented sedimentological findings with foreland basins located in …

Tectonics And Sedimentary Facies Interpretation Of The Mesozoic Giron Group, Colombia, Hernando Martinez-Sacristan, Ricardo Mier-Umana, Nazrul I. Khandaker, Stanley Schleifer, Diana Lucia Leon-Martinez

Publications and Research

Preliminary field investigations involving exposed Giron Group sediments in Colombia provided some interesting geologic information in terms of provenance, depositional environments, and development of the Mesozoic synrift sedimentary basins in Colombia. Overall, the synrift Triassic-Jurassic rift-related volcanic rocks, redbeds, and evaporites are prominent in Colombia, and a thick basin sequence of Cretaceous sandstones and shales dominates the central part of the Cordillera Oriental. These were mostly deposited in dominantly north-trending grabens. Identified sedimentary rock types were arkose, clast-and-matrix-supported conglomerate, red mudstone, variegated sandstone, siltstone and breccia. Extensive kaolinitization was noticeable in several sandstone samples. Among the notable sedimentary structures were …

Muddy Creek Formation: A Record Of Late Neogene Tectonics And Sedimentation In Southern Nevada, Thomas William Muntean

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Late Neogene Muddy Creek Formation (MCF), exposed in the vicinity of Lake Mead in southern Nevada, represents the youngest widespread Cenozoic sedimentary sequence in the region and is the focus of this study. Historically, the MCF has been largely ignored, with limited previous studies providing only regional-scale constraint on the age, stratigraphy, and mode of deposition for the formation; resulting in a data gap for our understanding of the Late Cenozoic tectonic and sedimentological evolution of southern Nevada.

U/Pb Detrital Zircon Study Of The Upper Cretaceous To Miocene Strata Of Kodiak Island, Alaska, Sarah J. Olivas^, Cameron Davidson, John I. Garver, Diane I. Doser*, Hannah Hilbert-Wolf

COURI Symposium Abstracts, Spring 2012

No abstract provided.

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 …

Stratigraphic Record Of Holocene Coseismic Subsidence, Padang, West Sumatra, Tina Dura, Charles M. Rubin, Harvey M. Kelsey, Benjamin P. Horton, Andrea Hawkes, Christopher H. Vane, Mudrik Daryono, Candace Grand Pre, Tyler Landinsky, Sarah Bradley

All Faculty Scholarship for the College of the Sciences

Stratigraphic evidence is found for two coseismic subsidence events that underlie a floodplain 20 km south of Padang, West Sumatra along the Mentawai segment (0.5°S–0.3°S) of the Sunda subduction zone. Each earthquake is marked by a sharp soil‐mud contact that represents a sudden change from mangrove to tidal flat. The earthquakes occurred about 4000 and 3000 cal years B.P. based on radiocarbon ages of detrital plant fragments and seeds. The absence of younger paleoseismic evidence suggests that late Holocene relative sea level fall left the floodplain too high for an earthquake to lower it into the intertidal zone. Our results …

Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya

Department of Earth, Environment and Sustainability Faculty Publications

The objective of this encyclopedia is to present the current state of scientific understanding of various aspects of earth’s cryosphere – snow, glaciers, ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and permafrost – and their related interdisciplinary connections under one umbrella. Therefore, every effort has been made to provide a comprehensive coverage of cryosphere by including a broad array of topics, such as the atmospheric processes responsible for snow formation; snowfall observations; snow cover and snow surveys; transformation of snow to ice and changes in their properties; classification of ice and glaciers and their worldwide …

Timing, Distribution, Amount, And Style Of Cenozoic Extension In The Northern Great Basin, Christopher D. Henry, Allen J. Mcgrew, Joseph P. Colgan, Arthur W. Snoke, Matthew E. Brueseke

Department of Earth, Environment and Sustainability Faculty Publications

This field trip examines contrasting lines of evidence bearing on the timing and structural style of Cenozoic (and perhaps late Mesozoic) extensional deformation in northeastern Nevada. Studies of metamorphic core complexes in this region report extension beginning in the early Cenozoic or even Late Cretaceous, peaking in the Eocene and Oligocene, and being largely over before the onset of “modern” Basin and Range extension in the middle Miocene. In contrast, studies based on low- temperature thermochronology and geologic mapping of Eocene and Miocene volcanic and sedimentary deposits report only minor, localized extension in the Eocene, no extension at all in …

Geochemistry, Geothermobarometry And Geochronology Of High-Pressure Granulites And Implications For The Exhumation History Of Ultrahigh-Pressure Terranes: Dulan, Western China, Benjamin David Joseph Christensen

All Master's Theses

The Dulan ultrahigh-pressure (UHP) rocks of the North Qaidam terrane, Western China, represent continental crust that has been subducted ~100 km during continental collision. Adjacent granulites representing burial to ~50 km could either be overprinted eclogites or a separate high-pressure-high-temperature (HP-HT) granulite unit. Overprinted eclogites and HP-HT granulites imply different P-T-t paths for UHP rocks. Metamorphic conditions for the granulites are 750–880 °C and 14–17 kbar. Zircon U-Pb geochronology, REE patterns and Ti-in-zircon thermometry indicate an increase in temperature from ~800 °C (449 Ma) to ~900 °C (418 Ma). This temperature increase could explain the presence of granulite leucosomes and …

Upper Cretaceous Peay Bentonites (North-Central Wyoming): Provenance And Tectonics Interpretation From Ash Composition, Nazrul I. Khandaker, Carl F. Vondra, Karl E. Seifert, Malek Shami, Rochelle Cardinale, Thakur Chaturgan

Publications and Research

The Peay bentonites belong to the basal Frontier Formation (Bighorn Basin, north-central Wyoming), primarily outcrop in the Bighorn Basin, rest on an extensively bioturbated sandstone unit, the Peay Sandstone, and are generally the thinner bentonitic unit. Beds of very light gray to greenish gray bentonite are also abundant in the lower Frontier units between Kaycee and Mayoworth (Powder River Basin) and are very rarely as much as 3 m thick. Bentonite occurs within the interstratified shale, sandstone, and siltstone sequences of the lower Frontier unit throughout much of the southwestern Powder River Basin. The purpose of this study is to …

A Study Of Fold Characteristics And Deformation Style Using The Evolution Of The Land Surface: Zagros Simply Folded Belt, Iran, Caroline M. Burberry, John W. Cosgrove, Jian-Guo Liu

Department of Earth and Atmospheric Sciences: Faculty Publications

Deformation styles within a fold-thrust belt can be understood in terms of the spatial organization and geometry of the fold structures. In young fold-thrust belts such as the Zagros, this geometry is reflected topographically by concordant landform morphology. Thus, the distribution of deformation structures can be characterized using satellite image analysis, digital elevation models, the drainage network and geomorphological indicators. The two distinct fold types considered in this study (fault-bend folds and detachment folds) both trending NW-SE, interact with streams flowing NE-SW from the High Zagros Mountains into the Persian Gulf. Multiple abandoned stream channels cross fault-bend folds related to …

Understanding Paleoclimate And Human Evolution Through The Hominin Sites And Paleolakes Drilling Project, Andrew Cohen, Ramon Arrowsmith, Anna K. Behrensmeyer, Christopher Campisano, Craig Feibel, Shimeles Fisseha, Roy Johnson, Zelalem Bedaso, Charles Lockwood, Emma Mbua, Daniel Olago, Richard Potts, Kaye Reed, Robin Renaut, Jean-Jacques Tiercelin, Mohammed Umer

Department of Earth, Environment and Sustainability Faculty Publications

Understanding the evolution of humans and our close relatives is one of the enduring scientific issues of modern times. Since the time of Charles Darwin, scientists have speculated on how and when we evolved and what conditions drove this evolutionary story. The detective work required to address these questions is necessarily interdisciplinary, involving research in anthropology, archaeology, human genetics and genomics, and the earth sciences. In addition to the difficult tasks of finding, describing, and interpreting hominin fossils (the taxonomic tribe which includes Homo sapiens and our close fossil relatives from the last 6 Ma), much of modern geological research …