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Full-Text Articles in Geology

Nebraska Statewide Groundwater-Level Monitoring Report 2009, Jesse T. Korus Dr., Mark E. Burbach Jan 2009

Nebraska Statewide Groundwater-Level Monitoring Report 2009, Jesse T. Korus Dr., Mark E. Burbach

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Geogram 2008, David J. Keeling, Wku Department Of Geography And Geology Oct 2008

Geogram 2008, David J. Keeling, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Water Quality Impacts From Agricultural Land Use In Karst Drainage Basins Of Sw Kentucky And Sw China, Chris Groves, Ted Baker Sep 2008

Water Quality Impacts From Agricultural Land Use In Karst Drainage Basins Of Sw Kentucky And Sw China, Chris Groves, Ted Baker

Earth, Environmental, and Atmospheric Sciences Faculty Publications

Karst regions are composed of soluble rock, often limestone, which leads to the formation of fissures, sinkholes, and water flow conduits such as caves. Pollutants in karst waters tend to be quickly directed and concentrated into these subsurface conduits. As a result of this and other factors, water resources are especially sensitive to contamination and pollution in karst areas. Pollutant concentrations going into karst subsurface fluvial systems are often very similar to the concentrations surfacing at outlets such as springs. Areas connected by karst conduit flows must be distinctly determined and special attention should be given to water quality impacts …


Controls On Longitudinal Profiles In Headwater Rivers Of The Waipaoa Basin, North Island, New Zealand, David M. Livingston Aug 2008

Controls On Longitudinal Profiles In Headwater Rivers Of The Waipaoa Basin, North Island, New Zealand, David M. Livingston

All-Inclusive List of Electronic Theses and Dissertations

The longitudinal profiles of the adjacent Mangatu and Upper Waipaoa Rivers, of the Waipaoa basin of the North Island of New Zealand, differ in their form despite their similarity in size and that they flow over comparable bedrock. AdditionaJly, both basins have experienced an increase in sediment supply following deforestation during the 19th and 20th centuries. This research addresses how the deviations in the long profiles of the Mangatu and Upper Waipaoa Rivers have arisen and what effect the increased sediment loading has had on their form. Using methods similar to those of Hack (1957), who found that in same …


Pamphlet To Accompany Geologic Map Gmc-34: Geologic Map Of The O’Neill 1º X 2º Quadrangle, Nebraska, With Configuration Maps Of Surfaces Of Formations, Robert F. Diffendal Jr., Michael R. Voorhies, E. Jane Voorhies, H. E. Lagarry, C. L. Timperley, M. E. Perkins Jan 2008

Pamphlet To Accompany Geologic Map Gmc-34: Geologic Map Of The O’Neill 1º X 2º Quadrangle, Nebraska, With Configuration Maps Of Surfaces Of Formations, Robert F. Diffendal Jr., Michael R. Voorhies, E. Jane Voorhies, H. E. Lagarry, C. L. Timperley, M. E. Perkins

Robert F. Diffendal, Jr., Publications

This map is necessarily generalized. It is based primarily on data from 7.5’ surficial geologic quadrangle maps of the map area prepared by the authors principally from 1991 to 2000, from Voorhies (unpublished data, 1974), as well as data from test-hole drilling done across the quadrangle by the Conservation and Survey Division, University of Nebraska, and its cooperators over many years since the 1930s. For more detailed information, consult the geologic data files of the Conservation and Survey Division, School of Natural Resources, University of Nebraska-Lincoln. The quadrangle is mostly covered by vegetation and Holocene sediments. Limited good exposures of …


Middle Crustal Ductile Deformation Patterns In Southern Tibet: Insights From Vorticity Studies In Mabja Dome, Jackie Langille Jan 2008

Middle Crustal Ductile Deformation Patterns In Southern Tibet: Insights From Vorticity Studies In Mabja Dome, Jackie Langille

All Master's Theses

Mabja Dome, southern Tibet, exposes mid-crustal rocks proposed to have originated from a southward flowing mid-crustal channel. Kinematic, mean kinematic vorticity (Wm), and metamorphic petrography analyses on these mid-crustal rocks were performed to test this hypothesis. Kinematic indicators show a transition with structural depth from top-north and top-south shear to solely top-south shear. Along the northernmost transects, Wm in schists and orthogneisses range from 0.52–0.84 (63–36% pure shear). Wm for quartzites ranges from 0.9–0.99 (27–1% pure shear). Deformation temperatures increase from ~450 °C in the chloritoid-zone to ~700 °C in the sillimanite-zone and were recorded between ~35–16 Ma. These patterns …


The Global Stratotype Section And Point (Gssp) For The Base Of The Katian Stage Of The Upper Ordovician Series At Black Knob Ridge, Southeastern Oklahoma, Usa, Daniel Goldman, Stephen A. Leslie, Jaak Nõlvak, Seth Young, Stig M. Bergström, Warren D. Huff Dec 2007

The Global Stratotype Section And Point (Gssp) For The Base Of The Katian Stage Of The Upper Ordovician Series At Black Knob Ridge, Southeastern Oklahoma, Usa, Daniel Goldman, Stephen A. Leslie, Jaak Nõlvak, Seth Young, Stig M. Bergström, Warren D. Huff

Department of Earth, Environment and Sustainability Faculty Publications

The International Subcomission on Ordovician Stratigraphy (ISOS) of the International Commission on Stratigraphy (ICS) recently defined the base of the global Upper Ordovician Series to be at the first appearance datum (FAD) of the graptolite species Nemagraptus gracilis in the Fågelsång GSSP in southern Sweden. This designation recognized the tremendous utility for global correlation of the first appearance of a cosmopolitan taxon that occurs within a consistent succession of other first appearance datums (e.g., Finney and Bergström, 1986; Bergström et al., 2000). Current efforts by the ISOS have focused on subdividing the Upper Ordovician into three stages and choosing appropriate …


An Update On Groundwater Conditions At The Site Of The York College Cuny Campus In Southeastern Queens County, New York City, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Edward A. Molteni Oct 2007

An Update On Groundwater Conditions At The Site Of The York College Cuny Campus In Southeastern Queens County, New York City, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Edward A. Molteni

Publications and Research

The wells operated by the Jamaica Water Supply Company in Queens represent the only large scale utilization of groundwater for public water supply in New York City in recent years. These wells were shut down, for the most part, beginning in 1996. Since that time, water table elevations in the area, which had been drawn down by the withdrawal activity of the Jamaica Water Supply Company, have risen significantly causing some high groundwater problems, including flooding of basements. The New York City Department of Environmental Protection (NYCDEP) has held public hearings on a contemplated resumption of ground water withdrawal in …


Geogram 2007, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2007

Geogram 2007, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Contact Metamorphism In The Malashan Dome, North Himalayan Gneiss Domes, Southern Tibet: An Example Of Shallow Extensional Tectonics In The Tethys Himalaya, Tetsuo Kawakami, Mutsuki Aoya, Simon Wallis, Jeffrey Lee, Kentaro Terada, Yu Wang, Matt Heizler Sep 2007

Contact Metamorphism In The Malashan Dome, North Himalayan Gneiss Domes, Southern Tibet: An Example Of Shallow Extensional Tectonics In The Tethys Himalaya, Tetsuo Kawakami, Mutsuki Aoya, Simon Wallis, Jeffrey Lee, Kentaro Terada, Yu Wang, Matt Heizler

All Faculty Scholarship for the College of the Sciences

Combined petrographic, structural and geochronological study of the Malashan dome, one of the North Himalayan gneiss domes, reveals that it is cored by a Miocene granite, the Malashan granite, that intruded into the Jurassic sedimentary rocks of Tethys Himalaya. Two other granites in the area are referred to as the Paiku and Cuobu granites. New zircon SHRIMP U-Pb and muscovite and biotite 40Ar-39Ar dating show that the Paiku granite was emplaced during 22.2–16.2 Ma (average 19.3 ± 3.9 Ma) and cooled rapidly to 350–400 °C at around 15.9 Ma. Whole-rock granite chemistry suggests the original granitic magma …


Dundy County Test Hole Logs, Duane A. Eversoll Jan 2007

Dundy County Test Hole Logs, Duane A. Eversoll

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May Jan 2007

Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May

United States Geological Survey: Publications

This report summarizes the findings of a study conducted as a pilot for part of a park-wide monitoring program being developed for the Ozark National Scenic Riverways (ONSR) of southeastern Missouri. The objective was to evaluate using crayfish (Orconectes spp.) and Asian clam (Corbicula fluminea) for monitoring concentrations of metals associated with lead-zinc mining. Lead-zinc mining presently (2007) occurs near the ONSR and additional mining has been proposed. Three composite samples of each type (crayfish and Asian clam), each comprising ten animals of approximately the same size, were collected during late summer and early fall of 2005 …


Observation Of Microslip Dynamics At High-Speed Microcontacts, Brian Borovsky, Adam M. Booth, Erin Manlove Jan 2007

Observation Of Microslip Dynamics At High-Speed Microcontacts, Brian Borovsky, Adam M. Booth, Erin Manlove

Geology Faculty Publications and Presentations

The high-speed tribological properties of microscale contacts are studied using an indenter probe and quartz crystal microbalance. Elastic and dissipative shear forces are monitored as a function of contact radius for sapphire/gold interfaces with an adsorbed octadecanethiol monolayer. We observe shear force transitions understood as taking the interface from slipping to stuck conditions. We relate this behavior to the presence of interfacial microslip. Dynamic modeling shows that our observations are consistent with an interface that, when sliding, experiences full slip during half of each cycle. We discuss the implications for this technique as a sensitive probe of sliding friction.


High- And Ultrahigh-Pressure Metamorphism In The North Qaidam And South Altyn Terranes, Western China, Chris G. Mattinson, C. A. Menold, Jian-Xin Zhang, D. K. Bird Jan 2007

High- And Ultrahigh-Pressure Metamorphism In The North Qaidam And South Altyn Terranes, Western China, Chris G. Mattinson, C. A. Menold, Jian-Xin Zhang, D. K. Bird

All Faculty Scholarship for the College of the Sciences

The North Qaidam and South Altyn terranes extend approximately 1000 km across the northern Tibetan Plateau, and five localities preserve evidence of Early Paleozoic high-pressure (HP) or ultrahigh-pressure (UHP) metamorphism, including the presence of coesite, coesite pseudomorphs, and diamond. A review of the geology, petrology, and geochronology collected over the past 10 years since these localities were discovered supports a correlation of the North Qaidam and South Altyn terranes, offset 350-400 km across the Altyn Tagh fault. Geochronology interpreted to reflect eclogite-facies metamorphism yields ages between 500 and 420 Ma; detailed geochronology from one locality supports a protracted (tens of …


Water Resources And Geologic Field Trip In York And Seward Counties, Nebraska, Michael J. Jess, Mark Burbach Nov 2006

Water Resources And Geologic Field Trip In York And Seward Counties, Nebraska, Michael J. Jess, Mark Burbach

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Provenance Of A Garnet-Rich Beach Placer Deposit, Montauk Point, Long Island, Ny, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Olalekan Jemilugba Oct 2006

Provenance Of A Garnet-Rich Beach Placer Deposit, Montauk Point, Long Island, Ny, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Olalekan Jemilugba

Publications and Research

Garnet and magnetite rich sand, also enriched in monazite and zircon, has been observed and sampled near Montauk Point, Long Island. The sediment is derived from the glacial till and stratified drift of the Ronkonkoma Moraine by mechanical weathering and erosion due to wave action at Montauk Point, the headland on the eastern tip of Long Island. Sand sized sediment is moved westward along the southern shore of Long Island by longshore transport. The garnet and magnetite components of this sediment are significantly denser than the quartzo-feldspathic components. This allows for hydraulic segregation of these components, by wave action, …


Geogram 2006, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2006

Geogram 2006, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


The Jabal Qarah Caves Of The Hofuf Area, Northeastern Saudi Arabia: A Geological Investigation, Nazrul I. Khandaker, Mahbub Hussain, Fadhel Al-Khalifah Oct 2006

The Jabal Qarah Caves Of The Hofuf Area, Northeastern Saudi Arabia: A Geological Investigation, Nazrul I. Khandaker, Mahbub Hussain, Fadhel Al-Khalifah

Publications and Research

The Jabal Al Qarah Caves, located approximately 13 km east of Al Hofuf, Eastern Province of Saudi Arabia, are an intricate cave system developed in the calcareous sandstone, marl and clay of the Upper Miocene to Lower Pliocene Hofuf Formation. Physiographically, the hill of Jabal Al Qarah is an outlier mesa that is located at the eastern edge of the Shedgum Plateau, the southern extension of the As Summan Plateau, and the larger Syrian Plateau to the north. Based on cave morphology and interpreted evolutionary histoty, the Jabal Al Qarah caves appear to be significantly different from other limestone caves …


The Earth All Around Us Selected Building Stone In Lincoln, Nebraska, William J. Wayne Mar 2006

The Earth All Around Us Selected Building Stone In Lincoln, Nebraska, William J. Wayne

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


The Sparrow Surface Water-Quality Model: Theory, Application And User Documentation, G. E. Schwarz, A. B. Hoos, R. B. Alexander, R. A. Smith Jan 2006

The Sparrow Surface Water-Quality Model: Theory, Application And User Documentation, G. E. Schwarz, A. B. Hoos, R. B. Alexander, R. A. Smith

United States Geological Survey: Publications

SPARROW (SPAtially Referenced Regressions On Watershed attributes) is a watershed modeling technique for relating water-quality measurements made at a network of monitoring stations to attributes of the watersheds containing the stations. The core of the model consists of a nonlinear regression equation describing the non-conservative transport of contaminants from point and diffuse sources on land to rivers and through the stream and river network. The model predicts contaminant flux, concentration, and yield in streams and has been used to evaluate alternative hypotheses about the important contaminant sources and watershed properties that control transport over large spatial scales.

This report provides …


Tapeworms Of Elasmobranchs (Part Ii) A Monograph On The Diphyllidea (Platyhelminthes, Cestoda), Gaines Albert Tyler Ii Jan 2006

Tapeworms Of Elasmobranchs (Part Ii) A Monograph On The Diphyllidea (Platyhelminthes, Cestoda), Gaines Albert Tyler Ii

Bulletin of the University of Nebraska State Museum (1924–2023)

The main objective of this monograph was a synthesis of the available knowledge on the diversity, systematics, host associations, and biogeography of the Diphyllidea. A thorough review of the literature resulted in the transfer of Diagonobothrium into Diphyllidea as a genus inquirendum. The genus Yogeshwaria was also transferred to Diphyllidea as a synonym of Echinobothrium. Its only species, E. nagabhushani n. comb., is considered to be a species inquirenda. New collections resulted in the description of a new species of Echinobothrium. Type and/or voucher specimens for 32 of 36 valid diphyllidean species (including the new species) …


Mapping Of A Detachment Fault In Kythera Island And Study Of The Related Structural Shear Sense Indicators, Antonios Marsellos Jan 2006

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 …


Groundwater-Level Changes In Nebraska, Spring 2000 To Spring 2006/ Density Of Registered Irrigation Wells In Nebraska August 2005, Conservation Survey Division Jan 2006

Groundwater-Level Changes In Nebraska, Spring 2000 To Spring 2006/ Density Of Registered Irrigation Wells In Nebraska August 2005, Conservation Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Geochronology And Tectonic Significance Of Middle Proterozoic Granitic Orthogneiss, North Qaidam Hp/Uhp Terrane, Western China, Chris G. Mattinson, Joseph L. Wooden, Juhn G. Liou, D. K. Bird, C. L. Wu Jan 2006

Geochronology And Tectonic Significance Of Middle Proterozoic Granitic Orthogneiss, North Qaidam Hp/Uhp Terrane, Western China, Chris G. Mattinson, Joseph L. Wooden, Juhn G. Liou, D. K. Bird, C. L. Wu

All Faculty Scholarship for the College of the Sciences

Amphibolite-facies para- and orthogneisses near Dulan, in the southeast part of the North Qaidam terrane, enclose minor ultra-high pressure (UHP) eclogite and peridotite. Field relations and coesite inclusions in zircons from paragneiss suggest that felsic, mafic, and ultramafic rocks all experienced UHP metamorphism and a common amphibolite-facies retrogression. Ion microprobe U–Pb and REE analyses of zircons from two granitic orthogneisses indicate magmatic crystallization at 927 ± Ma and 921 ± 7 Ma. Zircon rims in one of these samples yield younger ages (397–618 Ma) compatible with partial zircon recrystallization during in-situ Ordovician-Silurian eclogite-facies metamorphism previously determined from eclogite and paragneiss …


Spatial Distributions Of Perchloroethylene Reactive Transport Parameters In The Borden Aquifer, Richelle M. Allen-King, Dana Divine, Michel J. L. Robin, J. Richard Alldredge, David R. Gaylord Jan 2006

Spatial Distributions Of Perchloroethylene Reactive Transport Parameters In The Borden Aquifer, Richelle M. Allen-King, Dana Divine, Michel J. L. Robin, J. Richard Alldredge, David R. Gaylord

Conservation and Survey Division: Faculty and Staff Publications

We determined the descriptive statistical and spatial geostatistical properties of the perchloroethene ln Kd and the ln k of a 1.5 m thick by 10 m horizontal transect of the Borden aquifer near the location of the Stanford-Waterloo (SW) tracer experiment. The ln Kd distribution is not normal and is right skewed because of a few high values that occur localized in two regions of the transect. In contrast, the ln k data can be characterized by a normal distribution. A linear regression of ln Kd on ln k yields a statistically significant positive correlation, also shown …


Observations Of Sand Waves, Megaripples, And Hummocks In The Dutch Coastal Area And Their Relation To Currents And Combined Flow Conditions, Sandra Passchier, Maarten Kleinhans Dec 2005

Observations Of Sand Waves, Megaripples, And Hummocks In The Dutch Coastal Area And Their Relation To Currents And Combined Flow Conditions, Sandra Passchier, Maarten Kleinhans

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

[1] This paper aims to investigate the distribution and stability of large‐scale bed forms in response to storm and fair‐weather conditions in a shallow marine environment. Multibeam and side‐scan sonar data off the Dutch coast (median grain size 0.25–0.35 mm) were collected to monitor sand waves (λ = 100–800 m) and superimposed megaripples (λ = 1–40 m) through multiple storm and fair‐weather events. Box cores were used to observe the vertical bed structure and grain size. In the Dutch coastal area, two‐dimensional (2‐D) megaripples (λ = 1–15 m) are the dominant bed forms in current‐dominated (>0.4 m/s) tidal flow …


Results Of Vadose Zone Sampling Within The Tri-Basin Natural Resources District, Mark E. Burbach Nov 2005

Results Of Vadose Zone Sampling Within The Tri-Basin Natural Resources District, Mark E. Burbach

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Geogram 2005, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2005

Geogram 2005, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


The Moxee City (Washington) Mammoth: Morphostratigraphic, Taphonomic, And Taxonomic Considerations, Karl Lillquist, Steve Lundblad, Bax R. Barton Oct 2005

The Moxee City (Washington) Mammoth: Morphostratigraphic, Taphonomic, And Taxonomic Considerations, Karl Lillquist, Steve Lundblad, Bax R. Barton

All Faculty Scholarship for the College of the Sciences

A nearly complete, but highly fractured, proboscidean tusk was unearthed during parking lot construction near Moxee City in central Washington in May 2001. Schreger angle analysis revealed that the tusk was from a mammoth. AMS radiocarbon dating of the tusk established that the mammoth died 14,570 14C yr BP. The age, combined with the biogeography of proboscidean finds in the Pacific Northwest, suggests the tusk is from a Columbian mammoth (Mammuthus columbi). The condition of the tusk and its association with basalt and crystalline erratics suggest that a locally derived tusk was swept up in the advancing …


Spatial And Temporal Variations In Epikarst Storage And Flow In South Central Kentucky’S Pennyroyal Plateau Sinkhole Plain, Chris Groves, Carl Bolster, Joe Meiman Sep 2005

Spatial And Temporal Variations In Epikarst Storage And Flow In South Central Kentucky’S Pennyroyal Plateau Sinkhole Plain, Chris Groves, Carl Bolster, Joe Meiman

Earth, Environmental, and Atmospheric Sciences Faculty Publications

The well-developed karst aquifers of south central Kentucky’s Pennyroyal Plateau are impacted by contamination from animal waste and other agricultural inputs. Understanding fate and transport of these and other contaminants first requires knowledge of flow and storage behaviors within the impacted aquifers, complicated by significant heterogeneity, anisotropy, and rapid temporal variations. Here we report on spatial and temporal variations in vadose zone flow and water chemistry (or quality) within Cave Spring Caverns, Kentucky beneath agricultural lands on a well-developed sinkhole plain. Weekly sampling of three underground waterfalls show statistically significant differences in water quality, though the sites are laterally within …