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Geology Of Southeastern Nebraska, Robert Matthew Joeckel, Dana Divine, Leslie M. Howard, Kathleen Cameron, Michele M. Waszgis 2019 University of Nebraska - Lincoln

Geology Of Southeastern Nebraska, Robert Matthew Joeckel, Dana Divine, Leslie M. Howard, Kathleen Cameron, Michele M. Waszgis

Conservation and Survey Division

No abstract provided.


Maps Showing The Physical Hydrogeology And Changes In Saturated Thickness (Predevelopment To Spring 2016 And Spring 2011 To Spring 2016) In The Middle Republican Natural Resources District, Southwestern Nebraska., Jesse T. Korus Dr., Leslie M. Howard 2019 University of Nebraska-Lincoln

Maps Showing The Physical Hydrogeology And Changes In Saturated Thickness (Predevelopment To Spring 2016 And Spring 2011 To Spring 2016) In The Middle Republican Natural Resources District, Southwestern Nebraska., Jesse T. Korus Dr., Leslie M. Howard

Conservation and Survey Division

This report accompanies fourteen new maps summarizing the hydrogeology and changes in saturated thickness in the Middle Republican Natural Resources District (MRNRD). The purpose of these maps is to assist the MRNRD in their groundwater management programs and in planning and installing an observation well network. Maps include:

• base of the principal aquifer;

• water table surfaces for predevelopment, Spring 2011, and Spring 2016;

• saturated thicknesses for predevelopment, Spring 2011, and Spring 2016;

• changes in saturated thickness (both in absolute magnitude and in percent) from predevelopment to Spring 2016 and from Spring 2011 to Spring 2016;

• …


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 2019 University of Montana, Missoula

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 …


An Analysis Of Fractures Around The Sevier Fault Zone Near Orderville, Utah, Charley H. Hankla 2019 The College of Wooster

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 …


Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona 2019 Central Washington University

Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona

All Master's Theses

Records of past tsunamis help constrain the long-term characteristics of megathrust earthquakes and elucidate the role of sea-level in the preservation of tsunami deposits. Near Queule, south-central Chile (39.3˚S, 73.2˚W), three sand layers interpreted as tsunami deposits are interbedded with dark, organic-rich, silt deposits along a tidal channel landward of a sand spit capped by eolian sand dunes. The uppermost sand layer is attributed to the tsunami from the Mw 9.5 1960 earthquake. The sand layer is widespread, tabular, oxidized, thins landward, and generally occurs at a depth of <20 cm. The spatial distribution of the deposit corresponds closely with the extent of the 1960 tsunami sand on 1961 aerial photographs. We computed numerical simulations of the 1960 tsunami in Queule using the GeoClaw finite-slip hydrodynamic model based on three published earthquake sources. The simulations showed inundation up to 4km inland that overtopped the coastal dunes; agreeing with historical documentation and testimonies of 1960 tsunami survivors. Stratigraphically below the 1960 tsunami deposit are two tabular, landward-thinning sand layers with sharp lower contacts above silty organic-rich layers. Combined radiocarbon ages of seeds, charcoal and wood fragments found at the contacts with the underlying organic layers yielded ages of 5460-5320 and 5990-5910 cal. years BP. These sand layers have similar distribution patterns to the 1960 sand layer, but are finer grained, thinner and less oxidized. Below this sequence of interbedded tsunami sands and silty organic layers there is an abrupt contact underlain by a distinct sequence of four inorganic silt layers alternating with dark brown organic-rich silts, which are older than 6280-6110 cal. years BP. The deepest studied layer is a thick, fine, gray sand. We interpret the gray sand as a submarine environment during the mid-Holocene sea-level high stand, and the alternating inorganic and organic silts as tidal to shallow sub-tidal environments, possibly indicating co-seismic land-level changes. Gradual sea level fall after the deposition of the two paleotsunami sand deposits that changed the geomorphology of the coast and limited the accommodation space necessary to preserve additional overwash sediments could explain the 5000-year hiatus with no evidence of earthquakes or tsunamis. Further research will offer possible explanations for the exception of the 1960 tsunami in breaking this long-term pattern.


Geomorphology Of Shell Ridges And Their Effect On The Stabilization Of The Biloxi Marsh, East Louisiana, Frances R. Crawford 2018 University of New Orleans

Geomorphology Of Shell Ridges And Their Effect On The Stabilization Of The Biloxi Marsh, East Louisiana, Frances R. Crawford

University of New Orleans Theses and Dissertations

Extensive shell ridges frame the edges of marsh platforms in parts of the Biloxi Marsh of southeast Louisiana. The exact sources of the shells in these accumulations have not been clearly identified but the most likely source is a combination of shells from modern offshore and shells excavated from buried St. Bernard delta deposits. Larger or fetch-protected ridges remain stable through time, whereas ridges facing open water are more mobile, moving as much as 38 m inland from July 2017 to January 2018. Behind stable ridges, marsh platform biomass is relatively unaffected. When ridges are mobile, vegetation is smothered, leaving …


An Analysis Of Mixed-Layer Clay Minerals And Major Element Geochemical Trends In Middle-Upper Pennsylvanian-Aged Paleosols As A Proxy For Characterizing Basin-Wide Diagenetic Patterns And The Paleoenvironment Of The Illinois Basin, U.S.A., Julia A. McIntosh 2018 Southern Methodist University

An Analysis Of Mixed-Layer Clay Minerals And Major Element Geochemical Trends In Middle-Upper Pennsylvanian-Aged Paleosols As A Proxy For Characterizing Basin-Wide Diagenetic Patterns And The Paleoenvironment Of The Illinois Basin, U.S.A., Julia A. Mcintosh

Earth Sciences Theses and Dissertations

Pennsylvanian-aged paleosols from four Illinois Basin (IB) cores were sampled to characterize clay mineralogy, paleosol morphology, and major element geochemistry. This data combined with X-ray diffraction (XRD) and X-ray fluorescence (XRF) data from two other stratigraphically equivalent cores were used to better understand basin-wide diagenetic patterns. Paleosols unimpacted by diagenesis are considered reliable proxies for continued geochemical analyses and paleoclimate interpretations of middle to late Pennsylvanian (Desmoinesian-Missourian) low-latitude environments.

Reichweite Ordering, as determined from XRD analysis ofprofiles, indicates that diagenesis impacted the deep interior of the basin and the southern portion of the basin. Further investigation of illitization mechanisms derived …


Hydrogeologic Framework Studies Of Portions Of The Niobrara River, Douglas R. Hallum, Steven S. Sibray, Leslie M. Howard 2018 University of Nebraska - Lincoln

Hydrogeologic Framework Studies Of Portions Of The Niobrara River, Douglas R. Hallum, Steven S. Sibray, Leslie M. Howard

Conservation and Survey Division

The Nebraska Department of Natural Resources (NeDNR) and Upper Niobrara-White Natural Resources District (UNWNRD) expressed interest in improving understanding and their ability to effectively manage water resources in and around a particular reach of the Niobrara River. Aquifer-thickness contours mapped by the Conservation and Survey Division (CSD) indicate that the principle aquifer has zero thickness in this area. Additionally, the statewide geologic bedrock map produced by CSD shows non-aquifer strata of the White River Group along the same reach, and this setting is consistent with the designation of an “aquifer absent area,” as in the present document. Water-management policy development …


Evaluating Stable Isotope And Geochronologic Techniques For Paleoclimate Reconstruction: Case Study Of The Santa Cruz Formation, Argentina, Robin B. Trayler 2018 Boise State University

Evaluating Stable Isotope And Geochronologic Techniques For Paleoclimate Reconstruction: Case Study Of The Santa Cruz Formation, Argentina, Robin B. Trayler

Boise State University Theses and Dissertations

Stable isotope analysis has become the method of choice for many studies investigating the paleoecology and paleoclimate of fossil mammal faunas. While organic tissues (collagen, keratins, proteins) persist for < 105 years highly mineralized tooth enamel is resistant to alteration and degradation and faithfully preserves its isotopic composition for millions (> 106) years. Reconstructing past climates from these records relies on both understanding both micro-scale mechanisms of isotope incorporation into individual teeth, and macro-scale changes in isotope compositions over hundreds of thousands or millions of years. In this dissertation I address three questions.

First, how does the geometry and …


Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa, Robert Hollis 2018 University of Southern Mississippi

Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa, Robert Hollis

Master's Theses

Coastal systems in the Gulf of Mexico are threatened to reduced sediment supply, storm impacts and relative sea level rise (RSLR). The geologic record can provide insights of geomorphic threshold crossings (formation, progradation, transgression, destruction) to these forcing mechanisms to predict future barrier evolution to climate change. The stratigraphic framework and antecedent topography directly influence coastal evolution over geologic timescales. This study synthesizes ~2100km of geophysical data, 700+ sediment cores, and 63 radiocarbon dates to regionally map two sequence boundaries, multiple ravinement surfaces and fourteen depositional facies. One marine isotope stage (MIS) 6 valley’s fill provided up to 300 x10 …


Subsurface Stratigraphic Interpretation Of The Lower Atoka Formation, Northern Arkoma Basin, Arkansas, William Stephen Denham 2018 University of Arkansas, Fayetteville

Subsurface Stratigraphic Interpretation Of The Lower Atoka Formation, Northern Arkoma Basin, Arkansas, William Stephen Denham

Graduate Theses and Dissertations

The Arkoma Basin is a Carboniferous peripheral foreland basin creating a structural depression covering an approximate area of 33,800 miles2 that extends through east-central Oklahoma and west-central Arkansas. The entire basin fill includes Pre-Mississippian carbonate shelf deposits, Mississippian marine carbonates and black shales, and Pennsylvanian mixed carbonated/clastic and shore zone/deltaic deposits. The Lower Atoka formation (Pennsylvanian) occurs in outcrop along the southern Boston Mountain Plateau in northern Arkansas and extends into the subsurface of the Arkoma Basin over an area of 2,300 miles2. The Lower Atoka ranges from 600 to 1500 feet in thickness and represents a cyclic succession of …


Sedimentology And Stratigraphy Of Core Stl14: An Early Pleistocene-To-Present Paleoclimate Archive From Stoneman Lake, Arizona, Spencer Staley 2018 University of New Mexico

Sedimentology And Stratigraphy Of Core Stl14: An Early Pleistocene-To-Present Paleoclimate Archive From Stoneman Lake, Arizona, Spencer Staley

Earth and Planetary Sciences ETDs

An 80 m lacustrine sediment core (STL14) from Stoneman Lake, Coconino County, Arizona, contains a sedimentary sequence of at least 1.5 million years, chronicling the complete history of basin infill and recording an extensive and high-resolution archive of climatic and hydrologic fluctuations. Lake levels in this small, internally-drained catchment are sensitive to changes in regional hydrologic balance. Consistent groundwater inflow, even during regionally dry episodes in the lake’s history, has prevented complete desiccation of the lake and sustained continuous lacustrine deposition except for one soil horizon. Multiproxy analysis of sedimentological indicators including lithofacies, color, wet bulk density, magnetic susceptibility, preliminary …


The Challenges Of Geotechnical Exploration In Bangladesh For Sustainable Urban Development And Risk Reductions In Engineering Geology, Mir Fazul Karim, Nazrul I. Khandaker, Muhammad Qumrul Hasson, A.T.M. Shakhawat Hossain 2018 Geotesting Express Inc.

The Challenges Of Geotechnical Exploration In Bangladesh For Sustainable Urban Development And Risk Reductions In Engineering Geology, Mir Fazul Karim, Nazrul I. Khandaker, Muhammad Qumrul Hasson, A.T.M. Shakhawat Hossain

Publications and Research

Bangladesh is a unique example of rapid urbanization where the urban population increased from 5 to 58 million in last four decades. Due to complex geology and active tectonic setting, the urban ground is impacted by fluvio-deltaic processes and regional seismicity. The densely populated cities of the country are facing risks from many natural hazards like floods, tidal surge, riverbank and coastal erosion, scour, landslides, soil collapse and foundation failures. Geologists anticipate severe seismic threats from yet-undefined tectonic structures and seek to determine their consequential geo-structural responses and conformance to the national building code. With rapid growth, demands on infrastructure …


Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights, R. M. Joeckel, Robert F. Diffendal, P. R. Hanson, Jesse T. Korus 2018 University of Nebraska-Lincoln

Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights, R. M. Joeckel, Robert F. Diffendal, P. R. Hanson, Jesse T. Korus

Robert F. Diffendal, Jr., Publications

Geologic mapping in Nebraska and environs is an ongoing endeavor that has spanned more than 170 years, involved dozens of scientists, and evolved through many changes. Digital mapping has risen to dominance in the state only since 1996. Geologic mapping in Nebraska today concentrates on surficial mapping, which emphasizes materials exposed at the land surface and their relationships with landforms, and which is particularly relevant because non- bedrock geologic materials (regolith) lie at the surface across at least 87% of the state. Moreover, surfi cial geologic maps assist the understanding of groundwater and sand and gravel resources, to name a …


New Insights Into Carboniferous Cyclothems. The Fourth Biennial Field Conference Of The American Association Of Petroleum Geologists (Aapg) Midcontinent Section Fourth Biennial Field Conference Abstracts And Guidebook, Robert Matthew Joeckel, Christopher R. Fielding 2018 University of Nebraska - Lincoln

New Insights Into Carboniferous Cyclothems. The Fourth Biennial Field Conference Of The American Association Of Petroleum Geologists (Aapg) Midcontinent Section Fourth Biennial Field Conference Abstracts And Guidebook, Robert Matthew Joeckel, Christopher R. Fielding

Conservation and Survey Division

The term “cyclothem” was coined by Wanless & Weller (1932) to describe repetitive stratigraphic successions of Carboniferous age in Illinois. Nonetheless, comparable rhythmicity had been identified in Carboniferous rocks both in the central and eastern USA, and in Europe during the preceding century. Cyclothems were found to comprise repetitive vertical successions of sandstones, heterolithic (thinly interbedded) sandstones and mudrocks, mudrocks, limestones, and coals, in many cases with pedogenic overprinting of these lithologies. As usage of the term “cyclothem” increased, so did the diversity of successions to which the term was applied, to the point where many geologists advocated abandonment of …


Mass-Transport Deposits In The Northern Gulf Of Mexico And Their Implications For Hydrocarbon Exploration, Michael Raymond Arthur 2018 Western Kentucky University

Mass-Transport Deposits In The Northern Gulf Of Mexico And Their Implications For Hydrocarbon Exploration, Michael Raymond Arthur

Masters Theses & Specialist Projects

This study investigates Mio-Pliocene mass-transport deposits (MTDs) in an understudied, hydrocarbon-rich region of the northeastern Gulf of Mexico. The research utilizes a high-quality 3D seismic dataset with an area of 635 km2, along with wireline logs and biostratigraphic data. With the help of quantitative seismic geomorphology techniques, detailed mapping of MTDs suggests a complex erosional and depositional history. Deposition of a MTD unit resulted in a 180 m topographic high that substantially influenced the distribution and morphology of subsequent MTDs, specifically the bifurcation of later mass-transport flows. This bifurcation contributed to the generation of a non-shielded erosional remnant with an …


Taxonomy, Taphonomy, And Bioerosion Of Lamniform And Carcharhiniform Shark Teeth From Onslow Bay, North Carolina And An Example Extension From The Gulf Coastal Plain Of The U.S.A., Harry M. Maisch IV 2018 The Graduate Center, City University of New York

Taxonomy, Taphonomy, And Bioerosion Of Lamniform And Carcharhiniform Shark Teeth From Onslow Bay, North Carolina And An Example Extension From The Gulf Coastal Plain Of The U.S.A., Harry M. Maisch Iv

Dissertations, Theses, and Capstone Projects

This dissertation is divided into four sections that feature assemblages of self-collected fossils recovered while SCUBA diving in Onslow Bay, North Carolina, and the Ouachita River near Malvern, Arkansas. Sections one through three focus on Cenozoic lamniform and carcharhiniform shark teeth, including those of large Otodus megalodon, collected from submerged, actively forming lag deposits adjacent to outcrops of the Miocene Pungo River and Pliocene Yorktown formations in Onslow Bay. Section one documents the submerged collecting localities and the taxonomy and biostratigraphic properties of the fossil shark teeth they contain. Section two documents bathymetric controls on the degree of taphonomic …


County-Wide Assessment Of Irrigation Expansion On Air Temperature, Humidity And Evapotranspiration Rates In Nebraska, 1979-2015, Jozsef Szilagyi 2018 Conservation and Survey Division, School of Natural Resources

County-Wide Assessment Of Irrigation Expansion On Air Temperature, Humidity And Evapotranspiration Rates In Nebraska, 1979-2015, Jozsef Szilagyi

Conservation and Survey Division

Total irrigated land area has been expanding in Nebraska over the last 40 years, propelling the state into a leading position within the US in terms of irrigated acreages. Typically, those counties which display the largest degree of irrigation development had a significant portion of their land area already irrigated in 1978. Large-scale irrigation in Nebraska affects its atmospheric environment. During the typical irrigation season of May to August, counties with the largest rate of irrigation expansion have cooled by about 0.2 – 0.3 °F per decade in the summer months of June, July and August, while counties with the …


The Periglacial Landscape Of Mars: Insight Into The 'Decameter-Scale Rimmed Depressions' In Utopia Planitia, Arya Bina 2018 The University of Western Ontario

The Periglacial Landscape Of Mars: Insight Into The 'Decameter-Scale Rimmed Depressions' In Utopia Planitia, Arya Bina

Electronic Thesis and Dissertation Repository

Currently, Mars appears to be in a ‘frozen’ and ‘dry’ state, with the clear majority of the planet’s surface maintaining year-round sub-zero temperatures. However, the discovery of features consistent with landforms found in periglacial environments on Earth, suggests a climate history for Mars that may have involved freeze and thaw cycles. Such landforms include hummocky, polygonised, scalloped, and pitted terrains, as well as ice-rich deposits and gullies, along the mid- to high-latitude bands, typically with no lower than 20o N/S. The detection of near-surface and surface ice via the Phoenix lander, excavation of ice via recent impact cratering activity as …


Sequence Stratigraphy Of Campanian-Maastrichtian Strata In Eastern Alabama, David Simmons 2018 University of Southern Mississippi

Sequence Stratigraphy Of Campanian-Maastrichtian Strata In Eastern Alabama, David Simmons

Master's Theses

Eastern Alabama is an area of interest due to the transition from the Gulf Coastal Plain to the Atlantic Coastal Plain. Coastal Plain investigations have been sparse compared to research conducted in the oil rich areas down dip in the Gulf of Mexico. A sequence stratigraphic framework using the T-R cycle methodology of Embry (2002) has been established by integrating surface and subsurface lithologic data with biostratigraphic zonations into Petra ®. High sedimentation from the ancestral Chattahoochee River and lower relative sea-level formed an additional depositional sequence within the Santonian-Campanian aged Blufftown Formation in eastern Alabama. The sequence is approximately …


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