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Full-Text Articles in Geology

Turbulent Lifestyle: Microbial Mats On Earth’S Sandy Beaches—Today And 3 Billion Years Ago, Nora Noffke Jan 2008

Turbulent Lifestyle: Microbial Mats On Earth’S Sandy Beaches—Today And 3 Billion Years Ago, Nora Noffke

OES Faculty Publications

Archean Earth history is very difficult to reconstruct. Until recently, only bacterial cells preserved in chert, microborings, and stromatolites provided the few clues to ancient life. Now, siliciclastic “microbially induced sedimentary structures” (MISS) are adding to our knowledge of both past life and paleoenvironments. MISS rise from the interaction of photoautotrophic microbial mats with physical sediment dynamics in siliciclastic, shallow-marine settings. Archean MISS can be understood through observations of living microbial mats and modern biotic-physical sedimentary processes. Such geobiological studies are key to the interpretation of the early evolution of prokaryotes. For example, the 2.9 Ga Pongola Supergroup, South Africa, …


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 …


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.


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.


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.


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) …


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.


Plant Paleoecology Of The Late Devonian Red Hill Locality, North-Central Pennsylvania, An Archaeopteris-Dominated Wetland Plant Community And Early Tetrapod Site., Walter L. Cressler Iii Jan 2006

Plant Paleoecology Of The Late Devonian Red Hill Locality, North-Central Pennsylvania, An Archaeopteris-Dominated Wetland Plant Community And Early Tetrapod Site., Walter L. Cressler Iii

Earth & Space Sciences Faculty Publications

The Late Devonian Red Hill locality in north-central Pennsylvania contains an Archaeopteris-dominated plant fossil assemblage, a diverse fossil fauna, and an extensive sedimentary sequence ideal for investigating the landscapes and biotic associations of the earliest forest ecosystems. Sedimentological analysis of the main plantfossil bearing layer at Red Hill indicates that it was a fl ood-plain pond. A seasonal wet-and-dry climate is indicated by well-developed paleovertisols. The presence of charcoal interspersed with plant fossils indicates that fi res occurred in this landscape.Fires appear to have primarily affected the fern Rhacophyton. The specifi city of the fires, the distribution profi …


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 …


Foraminiferal Faunas Of The Southern California Bight: A Temporal And Spatial Comparison Of Assemblages In The >150, 63-150, And >63 Μm Fractions, Amanda S. Shepard Dec 2005

Foraminiferal Faunas Of The Southern California Bight: A Temporal And Spatial Comparison Of Assemblages In The >150, 63-150, And >63 Μm Fractions, Amanda S. Shepard

All-Inclusive List of Electronic Theses and Dissertations

Analyses ofliving (Rose Bengal stained) deep-sea benthic foraminifera collected on the Southern California margin reveal temporal and spatial changes in foraminiferal assemblages related to changes in sea-surface productivity. Samples were collected from two sites in May, August, and October 1996. Results show that foraminiferal microhabitats are not static at these sites, and some species ( e.g., Bolivina spissa and Uvigerina peregrina) responded to the change in seasons with a change in their vertical distribution profiles, which is indicative of microhabitat preferences. Species such as Buliminella tenuata changed sediment depth in different stages of their life cycles, which has implications for …


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.


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 …


Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar Mar 2005

Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar

Department of Earth, Environment and Sustainability Faculty Publications

Meteorological data collected near the snout of the Gangotri Glacier suggest that the study area receives less rainfall. The average seasonal rainfall is observed to be about 260 mm. The rainfall distribution does not show any monsoon impact. Amount of seasonal rainfall is highly variable (131.4-368.8 mm) from year to year, but, in general, August had the maximum rainfall. A verage daily maximum and minimum temperatures were 14.7 and 4.1°C respectively, whereas average mean temperature was 9.4°C. July was recorded as the warmest month. During daytime, wind speed was four times higher than that at night-time. The average daytime and …


New Approaches To Understanding The Mechanics Of Burgess Shale-Type Deposits: From The Micron Scale To The Global Picture, Robert Gaines, Mary L. Droser Jan 2005

New Approaches To Understanding The Mechanics Of Burgess Shale-Type Deposits: From The Micron Scale To The Global Picture, Robert Gaines, Mary L. Droser

Pomona Faculty Publications and Research

Cambrian Burgess Shale-type (BST) deposits are among the most significant deposits for understanding the “Cambrian explosion” because they contain the fossilized tissues of nonmineralized organisms and provide a substantially different window on the radiation of the Metazoa than is afforded by the more “typical” fossil record of skeletal parts of biomineralized organisms. Despite nearly a century of research, BST deposits remain poorly investigated as sedimentologic entities largely because they comprise fine-grained mudrocks. Here,we describe a new, integrative approach to understanding a single BST deposit, the middle Cambrian Wheeler Formation of Utah, which reveals a dynamic interplay of paleoenvironmental, paleoecologic, and …


Tapeworms Of Elasmobranchs (Part I) A Monograph On The Lecanicephalidea (Platyhelminthes, Cestoda), Kirsten Jensen Jan 2005

Tapeworms Of Elasmobranchs (Part I) A Monograph On The Lecanicephalidea (Platyhelminthes, Cestoda), Kirsten Jensen

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

This represents the first monographic and phylogenetic treatment of the order Lecanicephalidea. The main objective was to treat the Lecanicephalidea at the generic level, while providing information on morphology, taxonomic history, phylogenetic relationships, geographic distribution, and host associations of the group. Following an introduction to the morphology of the Lecanicephalidea, the phylogenetic placement of the group is addressed. This is followed by a review of the taxonomic history of the group and relationships within, including summaries of 29 previously used classification schemes. Despite the generic focus of this study, the taxonomic status of 137 previously recognized lecanicephalidean species was evaluated, …


Palaeogeography And Fluvial To Estuarine Architecture Of The Dakota Formation (Cretaceous, Alvian), Eastern Nebraska, Usa, Robert Matthew Joeckel, G. A. Ludvigson, B. J. Witzke, E. P. Kvale, P. L. Phillips, R. L. Brenner, S. G. Thomas, L. M. Howard Jan 2005

Palaeogeography And Fluvial To Estuarine Architecture Of The Dakota Formation (Cretaceous, Alvian), Eastern Nebraska, Usa, Robert Matthew Joeckel, G. A. Ludvigson, B. J. Witzke, E. P. Kvale, P. L. Phillips, R. L. Brenner, S. G. Thomas, L. M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Variability Of Sea Ice Cover In The Chukchi Sea (Western Arctic Ocean) During The Holocene, Anne De Vernal, Claude Hillaire-Marcel, Dennis A. Darby Jan 2005

Variability Of Sea Ice Cover In The Chukchi Sea (Western Arctic Ocean) During The Holocene, Anne De Vernal, Claude Hillaire-Marcel, Dennis A. Darby

OES Faculty Publications

Dinocysts from cores collected in the Chukchi Sea from the shelf edge to the lower slope were used to reconstruct changes in sea surface conditions and sea ice cover using modern analogue techniques. Holocene sequences have been recovered in a down-slope core (B15: 2135 m, 75°44'N, sedimentation rate of ~1cm kyr-1) and in a shelf core (P1: 201 m, 73°41'N, sedimentation rate of ~22 cm kyr-1). The shelf record spanning about 8000 years suggests high-frequency centennial oscillations of sea surface conditions and a significant reduction of the sea ice at circa 6000 and 2500 calendar (cal) …


Registered Irrigation Wells In Nebraska August 2005, Conservation And Survey Division Jan 2005

Registered Irrigation Wells In Nebraska August 2005, Conservation And Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Agenda: Introduction To The Legal Foundation Of Federal Land Management, University Of Colorado Boulder. Natural Resources Law Center Dec 2004

Agenda: Introduction To The Legal Foundation Of Federal Land Management, University Of Colorado Boulder. Natural Resources Law Center

Introduction to the Legal Foundation of Federal Land Management (December 1-3)

Materials prepared for the course held at the National Center for Atmospheric Research in Boulder, Colorado on December 1-3, 2004

Course instructors: Charles Wilkinson; Sarah Krakoff; Kathryn Mutz; Ann Morgan; Maggie Fox

Contents:

Introduction -- Agenda -- Summaries of laws -- Case studies. Travel management; Oil and gas development; Timber/fuels reduction -- How to influence agency decision makers -- Natural resource related legal and policy resources for the non-legal professional


Introduction To The Legal Foundation Of Federal Land Management, University Of Colorado Boulder. Natural Resources Law Center Dec 2004

Introduction To The Legal Foundation Of Federal Land Management, University Of Colorado Boulder. Natural Resources Law Center

Introduction to the Legal Foundation of Federal Land Management (December 1-3)

1 v. (various pagings) : ill., maps ; 28 cm

Materials prepared for the course held at the National Center for Atmospheric Research in Boulder, Colorado on December 1-3, 2004

Course instructors: Charles Wilkinson; Sarah Krakoff; Kathryn Mutz; Ann Morgan; Maggie Fox

Contents:

Introduction -- Agenda -- Summaries of laws -- Case studies. Travel management; Oil and gas development; Timber/fuels reduction -- How to influence agency decision makers -- Natural resource related legal and policy resources for the non-legal professional


Groundwater-Level Changes In Nebraska - Spring 2002 To Spring 2003/Groundwater-Level Changes In Nebraska - Predevelopment To Spring 2003, Conservation Survey Division Jan 2004

Groundwater-Level Changes In Nebraska - Spring 2002 To Spring 2003/Groundwater-Level Changes In Nebraska - Predevelopment To Spring 2003, Conservation Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


A Holocene Record Of Changing Arctic Ocean Ice Drift Analogous To The Effects Of The Arctic Oscillation, Dennis A. Darby, Jens F. Bischof Jan 2004

A Holocene Record Of Changing Arctic Ocean Ice Drift Analogous To The Effects Of The Arctic Oscillation, Dennis A. Darby, Jens F. Bischof

OES Faculty Publications

The Arctic Oscillation (AO) controls the configuration of the Transpolar Drift (TPD). If thicker ice from the Beaufort Gyre were exported, the volume of fresh water/sea ice in the Nordic seas would significantly increase, decreasing the formation of North Atlantic deep water. This would cool large parts of the Northern Hemisphere and affect global climate. Therefore, in order to understand how the global climate system functions, it is imperative to know how the TPD changed over the last millennium or more. The provenance of grains in a sediment core located near the confluence of the TPD and the Beaufort Gyre …


Mammals Of Carlsbad Caverns National Park, New Mexico, Kenneth N. Geluso, Keith Geluso Jan 2004

Mammals Of Carlsbad Caverns National Park, New Mexico, Kenneth N. Geluso, Keith Geluso

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

Carlsbad Cavern was established as a national park on 14 May 1930, after being designated as a national monument for nearly seven years. The park is located in southeastern New Mexico, and today it encompasses 189.3 km2 (73.1 mi2). Eighty-eight percent of the park lies in the rugged Guadalupe Mountains, while 12% is located on relatively flat land along the base of the mountains. The park contains a variety of habitats ranging from desert scrub at the lowest elevations to coniferous woodlands on the highest summits. Five months after Carlsbad Cavern was declared a national monument, Vernon …


Late-Holocene Dune Activity Linked To Hydrological Drought, Nebraska Sand Hills, Usa, Joseph A. Mason, James B. Swinehart, Ronald J. Goble, David B. Loope Jan 2004

Late-Holocene Dune Activity Linked To Hydrological Drought, Nebraska Sand Hills, Usa, Joseph A. Mason, James B. Swinehart, Ronald J. Goble, David B. Loope

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Lincoln County Test Hole Logs, James W. Goeke Jan 2004

Lincoln County Test Hole Logs, James W. Goeke

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Semianalytical Solutions For Stream Depletion In Partially Penetrating Streams, Xunhong Chen, Yanfeng Yin Jan 2004

Semianalytical Solutions For Stream Depletion In Partially Penetrating Streams, Xunhong Chen, Yanfeng Yin

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Hitchcock County Test Hole Logs, Duane A. Eversoll Jan 2004

Hitchcock County Test Hole Logs, Duane A. Eversoll

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Mcpherson County Test Hole Logs, James W. Goeke Jan 2004

Mcpherson County Test Hole Logs, James W. Goeke

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Webster County Test Hole Logs, Scott E. Summerside Jan 2004

Webster County Test Hole Logs, Scott E. Summerside

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Review Of Geologic Factors Affecting Underground Limestone Mining In The U.S. And An Overview Of Underground Limestone Mining In Nebraska, R. M. Joeckel Jan 2004

Review Of Geologic Factors Affecting Underground Limestone Mining In The U.S. And An Overview Of Underground Limestone Mining In Nebraska, R. M. Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.