Earth Sciences Commons^™

Age Of The Mono Lake Excursion And Associated Tephra, Larry Benson, Joseph Liddicoat, Joseph Smoot, Andrei Sarna-Wojcicki, Robert M. Negrini, Steve Lund

United States Geological Survey: Staff Publications

The Mono Lake excursion (MLE) is an important time marker that has been found in lake and marine sediments across much of the Northern Hemisphere. Dating of this event at its type locality, the Mono Basin of California, has yielded controversial results with the most recent effort concluding that the MLE may actually be the Laschamp excursion (Earth Planet. Sci. Lett. 197 (2002) 151). We show that a volcanic tephra (Ash #15) that occurs near the midpoint of the MLE has a date (not corrected for reservoir effect) of 28,620 ± 300 ¹⁴C yr BP (~32,400 GISP2 yr BP) …

Rare-Earth Elements And Nd And Pb Isotopes As Source Indicators For Labrador Sea Clay-Size Sediments During Heinrich Event 2, Larry V. Benson, Don Barber, John T. Andrews, Howard E. Taylor, Paul Lamothe

United States Geological Survey: Staff Publications

Elemental abundances and Nd and Pb isotope ratios were determined on samples from the carbonate-free, clay-size fractions of sediments from intervals above, within, and below Heinrich event 2 (H-2) in core HU87-9 from the Northwest Labrador Sea slope. In HU87-9, rare-earth element (REE) distributions and elemental concentrations within the H-2 event are distinct from those outside this event. ɛ_Nd(0) and ²⁰⁶Pb/²⁰⁴Pb data also indicate different values for sediments deposited within and outside the H-2 event. Comparisons of REE patterns from the H-2 interval with those from bedrock units in Baffin Island, northern Quebec, and Labrador …

Response Of North American Great Basin Lakes To Dansgaard–Oeschger Oscillations, Larry Benson, Steve Lund, Robert M. Negrini, Braddock Linsley, Mladen Zic

United States Geological Survey: Staff Publications

We correlate oscillations in the hydrologic and/or cryologic balances of four Great Basin surface-water systems with Dansgaard– Oeschger (D–O) events 2–12. This correlation is relatively strong at the location of the magnetic signature used to link the lake records, but becomes less well constrained with distance/time from the signature. Comparison of proxy glacial and hydrologic records from Owens and Pyramid lakes indicates that Sierran glacial advances occurred during times of relative dryness. If our hypothesized correlation between the lake-based records and the GISP2 δ¹⁸O record is correct, it suggests that North Atlantic D–O stades …

Aeolian Cliff-Top Deposits And Buried Soils In The White River Badlands, South Dakota, Usa, J. Elmo Rawling Iii, Glen G. Fredlund, Shannon Mahan

United States Geological Survey: Staff Publications

Aeolian deposits in the North American Great Plains are important sources of Holocene palaeoenvironmental records. Although there are extensive studies on loess and dune records in the region, little is known about records in aeolian cliff-top deposits. These are common on table (mesa) edges in the White River Badlands. These sediments typically have loam and sandy-loam textures with dominantly very fine sand, 0.5–1% organic carbon and 0.5–5% CaCO₃. Some of these aeolian deposits are atypically coarse and contain granules and fine pebbles. Buried soils within these deposits are weakly developed with A-C and A-AC-C profiles. Beneath these are …

New Record Of The Rare Emballonurid Bat Centronycteris Centralis Thomas, 1912 In Costa Rica, With Notes On Feeding Habits, Neal Woodman

United States Geological Survey: Staff Publications

The shaggy sac-winged bat, Centronycteris centralis (Chiroptera: Emballonuridae), occurs mainly in lowland forests from Veracruz, Mexico, to Peru, although it has been reported from elevations as high at 1450 m in Panama (Simmons and Handley 1998; Hice and Solari 2002). Most captures of the species are of single individuals, and throughout its distribution, this bat is rare and poorly-known (Emmons 1997; Reid 1997; Simmons and Handley 1998). Centronycteris centralis generally has been assumed to be an aerial insectivore, capturing flying insects on the wing (Starrett and Casebeer 1968; Wilson 1973; Timm et al. 1989; LaVal and Rodrı´guez 2002). However, direct …

Quaternary Loess-Paleosol Sequences As Examples Of Climate-Driven Sedimentary Extremes, Daniel R. Muhs, E. Arthur Bettis Iii

United States Geological Survey: Staff Publications

Loess is a widespread, wind-transported, silt-dominated deposit that contains geologic archives of atmospheric circulation and paleoclimate on continents. Loess may cover as much as 10% of the Earth’s land surface. It is composed mainly of quartz, feldspars, and clay minerals, with varying amounts of carbonate minerals. The geochemistry of loess differs from region to region, depending on source materials, but all loess is very high in SiO2 with lesser amounts of other major elements. Trends in loess downwind from source areas include systematic decreases in thickness and amounts of sand and coarse silt, and increases in amounts of fine silt …

Variability Of Metals In Soils In The Sudbury Area (Ontario), Vera Spektor

Theses and Dissertations (Comprehensive)

Industrial development influences the natural and human environment. At the local scale, the most intensive industrial pollution is in the area of factories and industrial centers. Industrial pollution is concentrated in soil and vegetation (then, using water systems and trophic chains it may enter all ecosystem components). The industrial pollution of the Sudbury region includes mostly sulfur dioxide and heavy metals. The main goal of this study was to examine spatial variability in metal distribution in soil for the Sudbury area. Objectives of the work were to describe metal distribution depending on geographic factors such as topographic location, vegetation cover, …

Upper Spokane River Model: Model Calibration, 2001, Chris Berger, Robert Leslie Annear, Benjamin Welle

Civil and Environmental Engineering Faculty Publications and Presentations

The Upper Spokane River system under consideration is located in the Northeastern part of Washington State and runs from the Stateline with Idaho, River mile (RM) 96.0, downstream to Long Lake dam at RM 32.5. Figure 1 shows the river system and an outline the boundaries of the City of Spokane.

The Washington Department of Ecology (Ecology) is interested in a water quality model for the Upper Spokane River system for use in developing Total Maximum Daily Loads (TMDLs). As a result, Ecology and the Corps of Engineers funded a study to develop a water quality and hydrodynamic model of …

Ce-Qual-W2: A Two-Dimensional, Laterally Averaged, Hydrodynamic And Water Quality Model, Version 3.1, Thomas M. Cole, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

CE-QUAL-W2 is a two-dimensional, longitudinal/vertical, hydrodynamic and water quality model. Because the model assumes lateral homogeneity, it is best suited for relatively long and narrow waterbodies exhibiting longitudinal and vertical water quality gradients. The model has been applied to rivers, lakes, reservoirs, estuaries, and combinations thereof.

The application of CE-QUAL-W2 requires knowledge in the following areas: 1. Hydrodynamics 2. Aquatic biology 3. Aquatic chemistry 4. Numerical methods 5. Computers and FORTRAN coding 6. Statistics 7. Data assembly and reconstruction.

Water quality modeling is in many ways an art requiring not only knowledge in these areas but also experience in their …

Numerical And Granulometric Approaches To Geophysical Granular Flows , Sébastien Dartevelle

Dissertations, Master's Theses and Master's Reports - Open

Volcanic ash clouds can be fed by an upward-directed eruption column (Plinian column) or by elutriation from extensive pyroclastic-flows (coignimbrite cloud). For large-scale eruptions, there is considerable uncertainty about which mechanism is dominant. Here we analyze in a novel way a comprehensive grainsize database for pyroclastic deposits. We demonstrate that the Mount Pinatubo climactic eruption deposits were substantially derived from coignimbrite clouds, and not only by a Plinian cloud as generally thought. Coignimbrite ash-fall deposits are much richer in breathable <10 m ash (5–25 wt%) than pure Plinian ash at most distances from the source volcano. We also show that coignimbrite ash clouds, as at Pinatubo, are expected to be more water rich than Plinian clouds, leading to removal of more HCl prior to stratospheric injection, thereby reducing their atmospheric impact.

Notes On Eryx, Omega, And Ata, Victor Fet

Biological Sciences Faculty Research

Observations on several Nabokov’s works (Pale Fire, Lolita) where geographic or zoological names provide sources for puns and hidden parallels.

Late Miocene-Pliocene Detachment Faulting And Pliocene-Recent Basin-And-Range Extension Inferred From Dismembered Rift Basins Of The Salt Lake Formation, Se Idaho, Susanne U. Janecke, S. M. Carney, M. E. Perkins, J. C. Evans, P. K. Link, R. Q. Oaks Jr., B. P. Nash

Geosciences Faculty Publications

Geologic mapping, basin analysis, and tephra correlations in the Clifton and Malad City East 7.5-minute quadrangles in southeastern Idaho indicate that the modern Basin-and-Range topography is only a few million years old and was superimposed on unrelated rift basins associated with the ~12 to < 4 Ma Bannock detachment system. The Miocene-Pliocene Salt Lake Formation in the greater Cache Valley area was deposited during three sub-episodes of west-southwest extension on the Bannock detachment system.

Depositional systems within the Salt Lake Formation (>10.27 ± 0.07 Ma to < 5.1-4.4 Ma) evolved in response to the changing structural configuration of rift basins in the hanging wall of the Bannock detachment system. Early alluvial fans derived from the underlying Paleozoic rocks were replaced by broad, saline/alkaline lakes during the translation phase on the detachment fault. Later, as the hanging wall broke up internally, freshwater lakes and deltas occupied newly created NE-tilted half graben, and eventually filled them with braided streams. The Bannock detachment system collapsed the Cache-Pocatello Culmination of the dormant Sevier fold-and-thrust belt, much like the Sevier Desert Detachment collapsed the Sevier Culmination and the Wasatch Fault collapsed the Wasatch Culmination.

Deposition and tilting of the Salt Lake Formation ceased in the middle to late Pliocene (< 2 >Ma?) before uplift of the Clifton Horst along a new system of Basin-and-Range normal faults. This later episode of normal faulting uplifted and exposed metamorphic rocks in …

Anisotropy And Its Relation To Liquefaction Resistance Of Granular Material, Isao Ishibashi, Omer F. Capar

Civil & Environmental Engineering Faculty Publications

This research establishes quantitative relationships between soil's anisotropy and liquefaction resistance for granular materials. Uniform medium density (D_r = 50%) sand specimens were prepared using three different sample preparation techniques (air pluviated (AP), moist tamped (NIT), and moist vibrated (MV)) to create different initial soil fabrics. Undrained cyclic triaxial tests were then performed to determine the liquefaction resistance of each soil specimen. On the same specimens in the triaxial cell, vertical and horizontal compression wave velocities and vertical shear wave velocity (V_s) were measured using piezoelectric bender elements. Anisotropic (transversely isotropic) elastic constants of the soil specimens were …

New Evidence For Enhanced Ocean Primary Production Triggered By Tropical Cyclone, I. Lin, W. Timothy Liu, Chun-Chieh Wu, George T. F. Wong, Chuanmin Hu, Zhiqiang Chen, Wen-Der Liang, Yih Yang, Kon-Kee Liu

OES Faculty Publications

[1] New evidence based on recent satellite data is presented to provide a rare opportunity in quantifying the long-speculated contribution of tropical cyclones to enhance ocean primary production. In July 2000, moderate cyclone Kai-Tak passed over the South China Sea (SCS). During its short 3-day stay, Kai-Tak triggered an average 30-fold increase in surface chlorophyll-a concentration. The estimated carbon fixation resulting from this event alone is 0.8 Mt, or 2-4% of SCS's annual new production. Given an average of 14 cyclones passing over the SCS annually, we suggest the long-neglected contribution of tropical cyclones to SCS's annual new production may …

The Role Of Physical, Chemical, And Microbial Heterogeneity On The Field-Scale Transport And Attachment Of Bacteria, Brian J. Mailloux, Mark E. Fuller, Tullis C. Onstott, James Hall, Hailiang Dong, Mary F. Deflaun, Sheryl H. Streger, Randi K. Rothmel, Maria Green, Donald J. P. Swift, Jon Radke

OES Faculty Publications

A field-scale bacterial transport experiment was conducted at the Narrow Channel Focus Area of the South Oyster field site located in Oyster, Virginia. The goal of the field experiment was to determine the relative influence of subsurface heterogeneity and microbial population parameters on flow direction, velocity, and attachment of bacteria at the field scale. The field results were compared with results from laboratory-scale column experiments to develop a method for predicting field-scale bacterial transport. The field site is a shallow, sandy, unconfined, aerobic aquifer that has been characterized by geophysical, sedimentological, and hydrogeological methods. Comamonas sp. strain DA001 and a …

The Relationships Of Vegetation And Bird Communities With Landforms And Geomorphic Processes On The Central Niagara Escarpment (Ontario), Robert John Milne

Theses and Dissertations (Comprehensive)

This study has examined the relationships between geomorphic form and process, vegetation composition and dynamics, and avian populations for landscapes in the central Niagara Escarpment, Southern Ontario. This includes an area extending from Speyside Conservation area near Milton to Mono Cliffs Provincial Park north of Orangeville. Data was collected for geomorphic form and process parameters, vegetation species and structural parameters, and avian species. The physical parameters included a combination of landform characteristics including slope angle, aspect, and landscape position and geomorphic processes, such as creep and debris slides, measured as a level of disturbance. Human levels of disturbance were also …

John Russell Bozeman Papers, Zach S. Henderson Library Special Collections

Finding Aids

This collection consists of research materials belonging to Georgia Southern College instructor, John Russell Bozeman. Materials span 1948-1994 and include research files on beach erosion, the ecology of the Georgia barrier islands, and general information on Southeastern ecology and topography.

Find this collection in the University Libraries' catalog.

Biomechanical Reconstruction Of The Appendicular Skeleton In Three North American Jurassic Sauropods, Ray Wilhite

LSU Doctoral Dissertations

Forelimb and hindlimb articulation, reconstructed musculature, and function were examined in Apatosaurus, Diplodocus, and Camarasaurus. A technique was developed using a Microscribe three-dimensional digitizer to capture external morphological data for skeletal reconstruction and determination of taxonomically useful features. The appendicular musculature of Alligator mississippiensis was dissected to determine form, function, origin, and insertion of muscles to aid in reconstruction of sauropod musculature. Contrary to the literature, M. caudofemoralis longus was found to originate primarily from the lateral surfaces of the proximal chevrons instead of the bodies and transverse processes of the caudals, demonstrating that chevron morphology is indicative of the …

Minerogenesis Of Volcanic Caves Of Kenya, Paolo Forti, Ermanno Galli, Antonio Rossi

International Journal of Speleology

Kenya is one of the few countries in which karst cavities are scarce with respect to volcanic ones, which are widespread throughout the whole country. The great variability in lava composition allowed the evolution of very different cavities, some of which are amongst the largest lava tubes of the world. As normal for such a kind of cave, the hosted speleothems and cave minerals are scarce but important from the minerogenetic point of view. Anyway up to present no specific mineralogical research have been carried out therein. During the 8th International Symposium on Volcanospeleology, held in Nairobi in February 1998, …

Caves And Karsts Of Northeast Africa, William R. Halliday

International Journal of Speleology

At least potentially karstifiable rocks cover much of the surface of Egypt and northern Libya. Study of caves and other karstic features of this region has been hampered by lack of roads, rapid disintegration of the surface of friable, poorly consolidated limestone, wind-blown sand and other factors. Interbedding with marly aquicludes hampers speleogenesis locally. Calcareous and evaporite karsts are present, however, and their waters are important albeit generally limited resources. Large quantities of fresh water are lost through submarine springs downslope from Libya’s Gebel al Akhdar range; the caves and karst of that range may be among the world’s greatest. …

Contribution To The Speleology Of Sterkfontein Cave, Gauteng Province, South Africa, J. E. J. Martini, P. E. Wipplinger, H. F. G. Moen, A. Keyser

International Journal of Speleology

The authors present more data about the speleological aspect of the Sterkfontein Cave, famous for its bone breccia which yielded abundant hominid remains. They also briefly review the previous voluminous studies by numerous authors, which are mainly dealing with the paleontology, stratigraphy and sedimentology of the breccia. The present investigations were oriented to hitherto poorly investigated aspects such as detail mapping of the cave, its country rock stratigraphy and recording the underground extension of the basal part of the breccia body. The cave consists of a complex network of phreatic channels, developed along joints in Neoarchaean cherty dolostone over a …

Human Impact On Karst: The Example Of Lusaka (Zambia), Jo De Waele, Roberto Follesa

International Journal of Speleology

Lusaka, the capital of Zambia with over 2,000,000 inhabitants, is built on an extensive plateau composed mainly of schists and dolomitic marbles, constituting a very important aquifer that provides the city with almost half of its drinking water needs. Recent demographic growth, leading to uncontrolled urban expansion, and mismanagement of the water resource and of urban waste has lead, in the past 20 years, to an overexploitation of the aquifer and to a generalised water quality depletion, putting in serious danger the future social and economical development of the capital. This third world city has, for these reasons, become a …

Tree-Mould Caves In Slovakia, Ludovít Gaál

International Journal of Speleology

Four tube-shaped caves are described in this work, which origined in consequence of weathering the trees. Their length ranges from 5.8 to 17 m. All of them occur in neovolcanic rocks of Middle Slovakia, in epiclastic andesite conglomerates, breccias or in the tuffs. Some other caverns are close to the entrance of this caves, however they are inaccessible for a man. Thin rim of silicates (opal or chalcedony) occurs in some of them.

Multivariate Geostatistical Analysis With Application To A Western Australian Nickel Laterite Deposit, Ellen Bandarian

Theses : Honours

Although it can be time consuming and computationally more expensive to work with multivariate data, it is often desirable to exploit the relationships among and between the variables sampled across a study region. In most cases the availability of this secondary information can enhance the estimation of the primary variable(s). The aim of this research is to describe and then demonstrate the use of multivariate statistical methods in geostatistical analysis. The methods will be illustrated by application to a multivariate data set from an actual mineralisation. The data suite is known as MM22D and comes from the Murrin Murrin nickel …

Martel's Routes In Mammoth Cave, Kentucky, 1912, Trevor R. Shaw

International Journal of Speleology

Martel’s own copy of the Hovey 1912 guidebook to Mammoth Cave has his routes marked faintly in pencil on the printed cave plans. These plans are reproduced here, with his routes indicated on them. He generally followed the four standard tourist routes which now included Kaemper’s 1908 discoveries to Violet City, but instead of visiting the Maelstrom he went to Hovey’s Cathedral and Gerta’s Grotto.

Littoral Dripstone And Flowstone--Non-Spelean Carbonate Secondary Deposits, Danko Taborosi, Kevin Stafford

International Journal of Speleology

Speleothem-like dripstone and flowstone deposits can form in the non-spelean environments of marine notches on tropical carbonate coastlines. Hereby termed “littoral dripstone” and “littoral flowstone” to distinguish them from genuine cave deposits, they reflect the basic speleothem types: draperies, stalactites, stalagmites, and columns. Nevertheless, these formations lack the luster and crystallinity of cave analogues, and are not nearly as well-developed, dense, and massive. They are composed of layered microcrystalline aragonite and calcite, are generally highly porous, and invariably overlie dissolutional and bioerosional karren. Because true speleothems, often found in the remnants of solution voids breached by coastal erosion, are also …

Complex Decapod Burrows And Ecological Relationships In Modern And Pleistocene Intertidal Carbonate Environments, San Salvador Island, Bahamas, H. Allen Curran, Anthony J. Martin

Geosciences: Faculty Publications

Burrowing by thalassinidean shrimp in modern tropical, shallow-subtidal to intertidal carbonate environments is widespread and a powerful agent of bioturbation, particularly within sandy substrates. Deep and intense burrowing by callianassids commonly occurs along the intertidal margins of hypersaline lagoons throughout the Bahamas, such as Pigeon Creek on San Salvador Island, where the sediments of extensive sand flats are thoroughly bioturbated by Glypturusacanthochirus. In addition to dominating the deep-tier infauna, G. acanthochirus is a true ecosystem engineer, and its prodigious burrowing activity results in a highly mounded topography. On sand flats, individual sediment cones commonly coalesce with time to form large …

Assessment Of Selected Reef Sites In Northern And South-Central Belize, Including Recovery From Bleaching And Hurricane Disturbances (Stony Corals, Algae And Fish), Paulette M. Peckol, H. Allen Curran, Emily Y. Floyd, Martha L. Robbart, Benjamin J. Greenstein, Kate L. Buckman

Geosciences: Faculty Publications

The condition of coral. algal. and fish populations in fore reefs. patch reefs, and coral reef ridges was investigated at 13 sites along the northern and south-central Belize barrier reef during May 1999, documenting effects of the 1998 warming episode and Hurricane Mitch. We found high percentages of partial, or even complete, colony mortality of major reef-builders (Acropora palmata, the Montastraea annuluris species complex and Agaricia tenuifolia) that were rarely censused as recruits. A. tenuifolia, formerly a space-dominant coral in reef ridges, had incurred nearly 100% mortality after bleaching. Nearly 45% of the M. annurluris complex …

Assessment Of Coral Reefs Off San Salvador Island, Bahamas (Stony Coral, Algae And Fish Populations), Paulette M. Peckol, H. Allen Curran, Benjamin J. Greenstein, Emily Y. Floyd, Martha L. Robbart

Geosciences: Faculty Publications

During assessments at 11 shallow reef sites on an Salvador Island, Bahamas in .iunc I998 we found low prevalence of disease, bleaching, and recent partial-colon1 mortality among stony corals (10 cm minimum dixncter). Old partial-colony mortalit) was >50% in Acropora palmata; however, recent tissue losses were low and it had recruits at several sites. Total (recent + old) partial-colony mortality of the Montastraea annularis species complex exceeded 30% on leeward patch reefs and back reefs. Groupers (serranids), snappers (lutjanids), and grunts (haemulids) were rare. Parrotfishes (scarids) were uncommon at most sites and surgeonfishes (acanthurids) were the dominant herbivores. Macroalgae, particularly …

Development Of A Regional Curve To Relate Discharge And Drainage Area To Hydraulic Geometry For The Red River Of The North Basin, Melanie H. Johnson

Theses and Dissertations

Restoration of riparian corridors and stream channels is important for many reasons, including preserving water quality, maintaining channel stability and controlling floods. Regional hydraulic geometry curves allow estimation of stable hydraulic geometry relationships that are necessary to engineer successful restoration projects. These curves can also be used to approximate discharge data for ungaged streams with lmown hydraulic geometry and drainage area. Hydraulic geometry data were collected in the field for twenty-five stream gage sites in the Red River of the North Basin. Recurrence intervals for bankfull ranged from 1.2 to 1.6 years, with an average recurrence interval of 1.4. Discharge …