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Evolution Of The Cretaceous Calcareous Nanofossil Genus Eiffellithus And Its Biostratigraphic Significance, Jamie L. Shamrock, David K. Watkins

Department of Earth and Atmospheric Sciences: Faculty Publications

The calcareous nanofossil genus Eiffellithus is an important taxon of mid- to Upper Cretaceous marine sediments in biostratigraphy and paleoceanography. The definition of species within Eiffellithus have been both broadly interpreted and variably applied by nanofossil workers. This is particularly true for the Eiffellithus eximius plexus. While the taxonomy of mid-Cretaceous Eiffellithus species has recently been well-defined, the remaining 35 m.y. history of the genus has not been closely examined. Our investigation of Cenomanian to Maastrichtian sediments from the Western Interior Seaway, Gulf of Mexico, and Western Atlantic gives rise to six new species of Eiffellithus that can be reliably …

Geochemistry Of The Middle Miocene Collision-Related Yamadaği ( Eastern Anatolia) Calc-Alkaline Volcanics, Turkey, Taner Eki̇ci̇, Musa Alpaslan, Osman Parlak, Ali̇ Uçurum

Turkish Journal of Earth Sciences

Major, trace element and K-Ar age determinations are reported for a suite from the Yamadağı volcanics in the Eastern Anatolia. The exposed rocks mainly consist of medium-potassium calc-alkaline basaltic andesites, andesites and dacites. Petrographical data exhibit disequilibrium mineral textures, such as resorption of the ferromagnesian phases, clinopyroxene-mantled orthopyroxene, and sieve-textured plagioclases. The Yamadağı volcanics have a calk-alkaline character, and trace element characteristics exhibit that the volcanics resemble subduction zone volcanics and/or volcanics assimilated by continental crust. K/Ar age determinations show that the Yamadağı volcanics were formed during the 12 ± 0.5 - 15 ± 0.5 Ma time interval. Geochemical characteristics …

Pidoplitchkoviella Terricola – An Interesting Fungus From The Domica Cave (Slovakia), Alena Nováková

International Journal of Speleology

The microfungus Pidoplitchkoviella terricola – until now it was known only as Kirilenko´s specimen isolated from Quercus robur rhizosphere in Ukraine - was found in earthworm casts in the Domica Cave, NP Slovak Karst, Slovakia. A description and microphotographs of this strain are provided in this article.

Exploring The Secrets Of The Three-Dimensional Architecture Of Phototrophic Biofilms In Caves, Mònica Roldán, Mariona Hernández-Mariné

International Journal of Speleology

Caves with dim natural light, and lighted hypogean environments, have been found to host phototrophic microorganisms from various taxonomic groups. These microorganisms group themselves into assemblies known as communities or biofilms, which are associated with rock surfaces. In this work, the phototrophic biofilms that colonise speleothems, walls and floors in three tourist caves (Spain) were studied. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) were used to study these organisms and acquire three-dimensional data on their biofilm structure. CLSM was used in a multi-channel mode whereby the different channels map individual biofilm components. Cyanobacteria, green microalgae, diatoms, mosses …

Guanophilic Fungi In Three Caves Of Southwestern Puerto Rico, Ángel M. Nieves-Rivera, Carlos J. Santos-Flores, Frank M. Dugan, Thomas E. Miller

International Journal of Speleology

Fifty species of guanophilic (bat guano-loving) fungi were isolated from field-collected samples within three caves in southwestern Puerto Rico; most were mitosporic fungi (23 species). The caves studied were Cueva La Tuna (Cabo Rojo), Cueva de Malano (Sistema de Los Chorros, San Germán), and Cueva Viento (El Convento Cave-Spring System, Guayanilla-Peñuelas). The most conspicuous fungus by far was the zygomycete Circinella umbellata (Mucorales). Circinella umbellata dominated the bat guano incubation chambers (Petri dishes lined with sterile filter paper moistened with sterile water) at ambient laboratory conditions. Nineteen species of basidiomycetes (e.g., Ganoderma cf. resinaceum, Geastrum cf. minimum, Lepiota …

A Terminological Matter: Paragenesis, Antigravitative Erosion Or Antigravitational Erosion?, Giancarlo Pasini

International Journal of Speleology

In the speleological literature three terms are utilized to designate the “ascending erosion”: paragenesis (= paragénésis, coined in 1968), antigravitative erosion (= erosione antigravitativa, coined in 1966) and antigravitational erosion (wrong English translation of the Italian term erosione antigravitativa, utilized later on). The term paragenesis should be abandoned because of the priority of the term erosione antigravitativa - on the ground of the “law of priority” – and because of its ambiguous etimology. On the other hand, the term antigravitational erosion should be forsaken in favour of the term antigravitative erosion, given the meaning that the terms gravitation and gravity …

Detrital-Zircon Geochronology Of The Metasedimentary Rocks Of North-Western Graham Land, David L. Barbeau Jr, Justin T. Davis, Kendra E. Murray, Victor Valencia, George E. Gehrels, Khandaker M. Zahid, David J. Gombosi

Faculty Publications

Metasedimentary rocks constitute an important but comparatively poorly understood part of the Antarctic Peninsula. Herein we report single-grain U-Pb detrital-zircon ages from samples of the Trinity Peninsula and Botany Bay Groups of north-western Graham Land. All studied samples are dominated by a large and narrowly defined population of late Palaeozoic zircons. Significant early–middle Palaeozoic and minor Neoproterozoic and Mesoproterozoic sub-populations constitute the majority of pre-Carboniferous grains. These detrital-zircon age populations are consistent with sediment derivation entirely from western Gondwana sources. Despite the clear Gondwana signatures, our data suggest that the Trinity Peninsula Group province was either a parautochthonous peri-Gondwanan terrane …

Pilot Study: The Nature And Thickness Of The Unsaturated Zone And Delineation Of Confined Aquifers, Sue Olafsen Lackey, Les Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Holocene Carbon Burial By Lakes In Sw Greenland, N. J. Anderson, W. D'Andrea, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

The role of the Arctic in future global change processes is predicted to be important because of the large carbon (C) stocks contained in frozen soils and peatlands. Lakes are an important component of arctic landscapes although their role in storing C is not well prescribed. The area around Kangerlussuaq, SW Greenland (66–68°N, 49–54°W) has ex¬tremely high lake density, with ~20 000 lakes that cover about 14% of the land area. C accumulation rates and standing stock (kg C m⁻²), representing late- to mid-Holocene C burial, were calculated from AMS ¹⁴C-dated sediment cores from 11 lakes. Lake …

Towards The Standardization Of Sequence Stratigraphy, Octavian Catuneanu, V. Abreu, J. P. Bhattacharya, M. D. Blum, R. W. Dalrymple, P. G. Eriksson, Christopher R. Fielding, W. L. Fisher, W. E. Galloway, M. R. Gibling, K. A. Giles, J. M. Holbrook, R. Jordan, C. G. St.C. Kendall, B. Macurda, O. J. Martinsen, A. D. Miall, J. E. Neal, D. Nummedal, L. Pomar, H. W. Posamentier, B. R. Pratt, J. F. Sarg, K. W. Shanley, R. J. Steel, A. Strasser, M. E. Tucker, C. Winker

Department of Earth and Atmospheric Sciences: Faculty Publications

Sequence stratigraphy emphasizes facies relationships and stratal architecture within a chronological framework. Despite its wide use, sequence stratigraphy has yet to be included in any stratigraphic code or guide. This lack of standardization reflects the existence of competing approaches (or models) and confusing or even conflicting terminology. Standardization of sequence stratigraphy requires the definition of the fundamental model-independent concepts, units, bounding surfaces and workflow that outline the foundation of the method. A standardized scheme needs to be sufficiently broad to encompass all possible choices of approach, rather than being limited to a single approach or model.

A sequence stratigraphic framework …

Long-Legged Pursuit Carnivorans (Amphicyonidae, Daphoeninae) From The Earlymiocene Of North America, Robert M. Hunt Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

In the early Miocene, endemic North American amphicyonids of the subfamily Daphoeninae evolved a lineage of large beardogs adapted for prey pursuit over open terrain. Three species comprise this lineage, here placed in the genus Daphoenodon, subgenus Borocyon Peterson, 1910, the sister subgenus to the daphoenine beardog Daphoenodon (Daphoenodon). These species (Borocyon robustum, B. niobrarensis, B. neomexicanus, n. sp.) are distinguished by limbs modified for fore–aft motion and parasagittal alignment contributing to a lengthened stride. These adaptive features are most evident in the terminal species, B. robustum, where the forelimb is conspicuously …

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.

Forecasting The Combined Effects Of Urbanization And Climate Change On Stream Ecosystems: From Impacts To Management Options, Kären C. Nelson, Margaret A. Palmer, James E. Pizzuto, Glenn A. Moglen, Paul L. Angermeier, Robert H. Hilderbrand, Michael Dettinger, Katharine Hayhoe

United States Geological Survey: Staff Publications

Streams collect runoff, heat, and sediment from their watersheds, making them highly vulnerable to anthropogenic disturbances such as urbanization and climate change. Forecasting the effects of these disturbances using process-based models is critical to identifying the form and magnitude of likely impacts. Here, we integrate a new biotic model with four previously developed physical models (downscaled climate projections, stream hydrology, geomorphology, and water temperature) to predict how stream fish growth and reproduction will most probably respond to shifts in climate and urbanization over the next several decades.

Taxonomy Of Quaternary Deep-Sea Ostracods From The Western North Atlantic Ocean, Moriaki Yasuhara, Hisayo Okahashi, Thomas M. Cronin

United States Geological Survey: Staff Publications

Late Quaternary sediments from Ocean Drilling Program (ODP) Hole 1055B, Carolina Slope, western North Atlantic (32°47.041’ N, 76°17.179’ W; 1798 m water depth) were examined for deep-sea ostracod taxonomy. A total of 13 933 specimens were picked from 207 samples and c. 120 species were identified. Among them, 87 species were included and illustrated in this paper. Twenty-eight new species are described. The new species are: Ambocythere sturgio, Argilloecia abba, Argilloecia caju, Argilloecia keigwini, Argilloecia robinwhatleyi, Aversovalva carolinensis, Bythoceratina willemvandenboldi, Bythocythere eugeneschornikovi, Chejudocythere tenuis, Cytheropteron aielloi, Cytheropteron demenocali, Cytheropteron didieae, Cytheropteron richarddinglei, Cytheropteron fugu, Cytheropteron guerneti, Cytheropteron richardbensoni, Eucytherura hazeli, …

Climate Trends Of The North American Prairie Pothole Region 1906–2000, Bruce Millett, W. Carter Johnson, Glenn Guntenspergen

United States Geological Survey: Staff Publications

The Prairie Pothole Region (PPR) is unique to North America. Its millions of wetlands and abundant ecosystem goods and services are highly sensitive to wide variations of temperature and precipitation in time and space characteristic of a strongly continental climate. Precipitation and temperature gradients across the PPR are orthogonal to each other. Precipitation nearly triples from west to east from approximately 300 mm/year to 900 mm/year, while mean annual temperature ranges from approximately 1°C in the north to nearly 10°C in the south. Twentieth-century weather records for 18 PPR weather stations representing 6 ecoregions revealed several trends. The climate generally …

Climate Trends Of The North American Prairie Pothole Region 1906–2000, Bruce Millett, W. Carter Johnson, Glenn R. Guntenspergen

United States Geological Survey: Staff Publications

The Prairie Pothole Region (PPR) is unique to North America. Its millions of wetlands and abundant ecosystem goods and services are highly sensitive to wide variations of temperature and precipitation in time and space characteristic of a strongly continental climate. Precipitation and temperature gradients across the PPR are orthogonal to each other. Precipitation nearly triples from west to east from approximately 300 mm/year to 900 mm/year, while mean annual temperature ranges from approximately 1◦C in the north to nearly 10◦C in the south. Twentieth-century weather records for 18 PPR weather stations representing 6 ecoregions revealed several trends. The climate generally …

The Influence Of Fallback Foods On Great Ape Tooth Enamel, Paul J. Constantino, Peter W. Lucas, James J.-W. Lee, Brian R. Lawn

Biological Sciences Faculty Research

Lucas and colleagues recently proposed a model based on fracture and deformation concepts to describe how mammalian tooth enamel may be adapted to the mechanical demands of diet (Lucas et al.: Bioessays 30[2008] 374-385). Here we review the applicability of that model by examining existing data on the food mechanical properties and enamel morphology of great apes (Pan, Pongo, and Gorilla). Particular attention is paid to whether the consumption of fallback foods is likely to play a key role in influencing great ape enamel morphology. Our results suggest that this is indeed the case. We also consider the implications of …

Arkosic Rocks From The San Andreas Fault Observatory At Depth (Safod) Borehole, Central California: Implications For The Structure And Tectonics Of The San Andreas Fault Zone, S. D. Springer, James P. Evans, J. I. Garver, D. Kirschner, Susanne U. Janecke

Geosciences Faculty Publications

The San Andreas Fault Observatory at Depth (SAFOD) drill hole encountered indurated, high-seismic-velocity arkosic sedimentary rocks west of the active trace of the San Andreas fault in central California. The arkosic rocks are juxtaposed against granitic rocks of the Salinian block to the southwest and against fine-grained Great Valley Group and Jurassic Franciscan rocks to the northeast. We identify three distinct lithologic units using cuttings, core petrography, electrical resistivity image logs, zircon fission-track analyses, and borehole-based geophysical logs. The upper arkose occurs from 1920 to 2530 m measured depth (mmd) in the borehole and is composed of five structural blocks …

Formation Of Iron-Rimmed Sandstone Nodules On Earth; Terrestrial Analogue For The Formation Of Martian Blueberries?, Katherine Charlotte Muller

Masters Theses

"NASA's twin Mars Exploration Rovers, MER, Spirit and Opportunity, have identified numerous geologic features that hint at a watery past on Mars noted in Malik, 2004. Prominent among these features are the "Martian Blueberries" that occur as spherical hematite (Fe₂O₃) nodules. Hematite formation is facilitated by the presence of water, although there are presently no known sources of free liquid water on Mars. Chan et al., 2004 states that these "blueberries" are also similar to nodules found in the Jurassic aged Navajo Sandstone in Utah. An understanding of the processes controlling the formation of the Utah nodules may thus be …

Estimating Variation In Stiffness And Volume Change Of Clays From Geochemical And Index Properties, Cynthia Roxanna Zuniga

Open Access Theses & Dissertations

Clayey soils from six different locations in Texas were analyzed and evaluated with respect to their expansion and shrinkage and change in stiffness associated with moisture content variation. These soils consist of five high plasticity-index (PI) clays (PI greater than 25) and one low-PI clay (PI = 17). The behavior of the clays changes dramatically with moisture content fluctuation, thus causing stiffness and volume changes throughout the year. Total or differential volume movements caused by swell or shrinkage strains of expansive soils and reduction in modulus can exert enough pressure to damage the pavements and cause maintenance problems.

The intent …

Temporal And Geochemical Insights Related To Volcanic And Plutonic Activity Within Big Bend National Park, Texas, Daniel Paul Miggins

Open Access Theses & Dissertations

Big Bend National Park located in the southeastern part of the Trans-Pecos Magmatic Province in west Texas contains a diverse suite of volcanic and intrusive rocks. Ongoing geologic mapping, geochronology, and geochemical studies have focused on the timing and geological relationships associated with these volcanic and intrusive rocks. Igneous activity within Big Bend National Park occurred from 46.5 to 22.0 Ma. Precise 40Ar/39Ar and U-Pb zircon geochronology has resolved the timing of this activity into five discrete episodes: 1) eruption and emplacement of both intrusive and volcanic mafic rocks at 46.5 Ma followed by ~42.0 Ma mafic volcanic pulse; 2) …

Characterizing The Deformation Of Reservoirs Using Interferometry, Gravity, And Seismic Analyses, Cara Schiek

Open Access Theses & Dissertations

In this Dissertation, I characterize how reservoirs deform using surface and subsurface techniques. The surface technique I employ is radar interferometry, also known as InSAR (Interferometric Synthetic Aperture Radar). The subsurface analyses I explore include gravity modeling and seismic techniques consisting of determining earthquake locations from a small-temporary seismic network of six seismometers. These techniques were used in two different projects to determine how reservoirs deform in the subsurface and how this deformation relates to its remotely sensed surface deformation.

The first project uses InSAR to determine land subsidence in the Mimbres basin near Deming, NM. The land subsidence measurements …

Zinc And Copper Isotopes As Tracers Of Anthropogenic Contamination In A Sediment Core From An Urban Lake, Anita Thapalia

Open Access Theses & Dissertations

Concentration data alone are often insufficient to resolve metal sources. This study applies stable Zn and Cu isotopes to fingerprint and track the sources of these metals in a sediment core from Lake Ballinger near Seattle, Washington, USA. The base of the Lake Ballinger core pre-dates settlement in the region, while the upper sections record the impact of atmospheric emissions from the nearby Tacoma smelter, as well as Cu and Zn inputs from urban sources. δ⁶⁶Zn and δ⁶⁵Cu varied by 0.42 / and 0.29 /, respectively, over the >300 year core record. Isotopic changes were correlated …

Analytical Method Development For Determination Of Volatile Organic Compounds In Calcareous Desert Soil, Mary F. Turner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Soil sample preservation for volatile organic compound analysis generally requires short sample holding times or preservation of the sample's chemical constituents with sodium bisulfate (NaHSO 4 ). Calcareous soils cannot be preserved using NaHSO4 because effervescence will promote the loss of analytes, and short holding times before analysis are not practical for remote sampling locations. An experimental approach was developed for determination of volatile organic compounds (VOCs) in soil that utilizes solid sorbents for sample preservation and solid-phase microextraction (SPME) sample preparation technique coupled with gas chromatography/mass spectrometry (GC/MS) for analysis. Solid sorbents are used to sequester readily extractable (vapor …

Pleistocene Reorganization Of The Southern San Andreas Fault System, A. N. Steely, Susanne U. Janecke, G. J. Axen, R. J. Dorsey

Geosciences Faculty Publications

Structural and stratigraphic analyses along the western margin of the Salton Trough show that the San Andreas fault system was reorganized in early Pleistocene time from a system dominated by two fault zones (the San Andreas fault and the West Salton detachment fault) to a network of dextral faults that include the San Andreas and at least four dextral faults to the southwest. The San Felipe fault zone, one of these dextral faults, has ~5.8 ± 2.8 km of right separation and consists of three principal faults in the Peninsular Ranges. These are the San Felipe fault in the WNW, …

Variations In Sea Surface Roughness Induced By The 2004 Sumatra-Andaman Tsunami, O. A. Godin, V. G. Irisov, R. R. Leben, B. D. Hamlington, G. A. Wick

CCPO Publications

Observations of tsunamis away from shore are critically important for improving early warning systems and understanding of tsunami generation and propagation. Tsunamis are difficult to detect and measure in the open ocean because the wave amplitude there is much smaller than it is close to shore. Currently, tsunami observations in deep water rely on measurements of variations in the sea surface height or bottom pressure. Here we demonstrate that there exists a different observable, specifically, ocean surface roughness, which can be used to reveal tsunamis away from shore. The first detailed measurements of the tsunami effect on sea surface height …

Southern Ocean Globec Research And The Future, Eileen Hofmann

CCPO Publications

(First paragraph) The International Global Ocean Ecosystems Dynamics (GLOBEC) Programme will end in early 2010, after almost 20 years. GLOBEC science has provided fundamental changes in our understanding of the scales of interactions in marine ecosystems, alternative views of marine food webs, and the influence of humans in marine ecosystem processes. Since Southern Ocean GLOBEC (SO GLOBEC) was one of the regional research programmes it is appropriate to reflect on i) its specific contributions, ii) how these might guide future Southern Ocean research, and iii) the key gaps for our future understanding of Southern Ocean ecosystems and the impact that …

Annual And Transient Signatures Of Gas Exchange And Transport In The Castañar De Ibor Cave (Spain), Angel Fernandez-Cortes, Sergio Sanchez-Moral, Soledad Cuezva, Juan Carlos Cañaveras, Rafael Abella

International Journal of Speleology

The large microclimatic stability is a basic characteristic of the subterranean karst systems and causes a high sensitivity to changes in environmental conditions. High-accuracy monitoring of Castañar de Ibor cave (Spain) determined the temporal evolution of the aerodynamic processes and ventilation rate by tracking CO₂ and ²²²Rn levels over a twelve-month period. This cave is characterized by a very stable microclimate, with high and relatively constant radon content (the mean value is 32200 Bq/m³, roughly, and the standard deviation is 7600 Bq/m³) and a moderate and quite stable CO2 concentration (the mean value is …

Seeing Shifts: Ecologists' Lived Experiences Of Climate Change In Mountains Of The American West, Kimberly Ford Langmaid

Antioch University Dissertations & Theses

This study explores the lived experiences of field ecologists who research the effects of global climate change on mountain species and ecosystems in the American West. The purpose is to generate narrative descriptions of ecologists’ experiences in order to communicate about both the scientific ecology and human ecology of climate change. Twenty prominent field ecologists participated in this study. Interviews with ecologists were transcribed and analyzed using a hermeneutic phenomenological methodology. Eight experiential themes emerged through the process of data analysis, and these themes provide the structure for presenting narratives of ecologists’ experiences. The eight themes are: thinking ecologically, the …

Potential Export Of Unattached Benthic Macroalgae To The Deep Sea Through Wind Driven Langmuir Circulation, H. M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige

OES Faculty Publications

Carbon export to the deep sea is conventionally attributed to the sinking of open ocean phytoplankton. Here, we report a Langmuir supercell event driven by high winds across the shallow Great Bahama Bank that organized benthic non-attached macroalgae, Colpomenia sp., into visible windrows on the seafloor. Ocean color satellite imagery obtained before and after the windrows revealed a 588 km² patch that rapidly shifted from highly productive macroalgae to bare sand. We assess a number of possible fates for this macroalgae and contend that this event potentially transported negatively buoyant macroalgae to the deep Tongue of the Ocean …