Earth Sciences Commons^™

A Sea-Level Lowstand (Devil's Point Event) Recorded In Bahamian Reefs: Comparison With Other Last Interglacial Climate Proxies, Brian White, H. Allen Curran, Mark A. Wilson

Geosciences: Faculty Publications

Reprinted from: Benjamin J. Greenstein and Cindy K. Carney (eds.) Proceedings of the 10th Symposium on the Geology of the Bahamas and Other Carbonate Regions: San Salvador, Gerace Research Center

Geologic Hazards Associated With Shale Strata And Swelling Clays Within Fayetteville Quadrangle, Washington County, Arkansas, Maria E. King, Jack T. King, Stephen K. Boss

Journal of the Arkansas Academy of Science

No abstract provided.

Thermodynamic Properties Of Neutron-Rich Matter, Matt Tilley, Bao-An Li

Journal of the Arkansas Academy of Science

The mechanism of supernova explosion and properties of neutron stars are uniquely determined by the equation of state of neutron-rich matter. Using a phenomenological equation of state within a thermal model, we study thermodynamic properties of neutron-rich matter. In particular, we investigate chemical (diffusive) and mechanical (isothermal) instabilities of neutron-rich matter and their dependence on the nuclear equation of state. Both instabilities are found to be heavily dependent upon the isospin asymmetry, temperature, and density of neutron-rich matter. We show that the boundary of the chemical instability extends farther out into the density-isospin symmetry plane than that of the mechanical …

A Small Look At The Big Picture: Linking Geopotential Height Anomalies To Paleofloods On The Snake River, Idaho And Oregon, Gwendolyn Bernitha Rhodes

All Master's Theses

A combined paleoflood and flood hydroclimatology study on the Snake River in Idaho and Oregon suggests a link between floods and patters of geopotential height anomalies over the North Pacific Ocean. Examination of the paleoflood record in two 4-m (12 ft) tall terraces along the Hells Canyon reach of the Snake River in Idaho and Oregon shows evidence of at least twenty-two late-Holocene extreme floods that occurred approximately 5,000 years. The ages of paleoflood deposits at these sites fall into two time periods, from 5130 ± 40 to 1960 ± 40 yr BP and from 320 ± 40 yr BP …

Burakin Focus Catchment Report, Mike Clarke

Natural resources published reports

The Burakin Focus Catchment Project was developed between farmers and Agriculture _ Western Australia. The project was designed to give farmers an understanding of the salinity processes occurring within the Catchment and suggestions on appropriate management.

Work began in the Catchment early in 1999 and was complete at the end of 2000. Intensive hydrological investigations formed the basis of the study, which was complemented by surface water control and revegetation strategies. Agronomic issues associated with sandplain soils were raised by the farmers at the initial meeting and this led to a soil survey to determine the pH status of the …

Farming Systems To Manage Salinity. Farmer Directed Research, Development And Extension. Research Results 2001, Richard Olive

Natural resources published reports

More and more of Western Australia's agnicultural lands are becoming saline. Currently it is estimated that about 18 milliion ha of land are affected to a greater or lesser degree by salinity causing production losses estimated at about $70 million a year.

Unless ways are found to halt and reverse the salinisation of land it is estimated that another 4.4 million ha could become saline over the next 50 years.

Grain growers and the Federal Government, through the Grains Research and Development Corporation (GRDC). are investing $12 4 million in R&D across Australia to develop productive solutions to the salinity …

Soilguide (Soil Guide) : A Handbook For Understanding And Managing Agricultural Soils, Geoff Allan Moore

Bulletins 4000 -

This handbook integrates the current knowledge of soils in south-western Australia in a user-friendly form. It describes how to assess which soil properties influence production and land degradation in the agricultural area and summarises management options to remedy or minimise soil limitations. The potential for growing a large range of crops and pastures can be assessed. In particular, the links between soil morphology, soil properties, management and agronomy are emphasised. The manual is designed for use at the paddock scale or for site assessment, but it can also be used at a catchment or regional scale. It is specifically designed …

Glacial Deposits, Vol. 29, 2000-2001, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology

The Assessment Of Satellite Remote Sensing As A Tool For Determining Sea Surface Temperatures In Nearshore Environments, Fabienne Faskel

Theses : Honours

The use of satellite remote sensing for environmental management applications has seen a marked increase over the past decade. Remotely sensed data are obtainable for a variety of parameters, such as mineral exploration, species migration, and for determining sea surface temperatures (SSTs). This study examined whether satellite remote sensing is a viable option for determining SSTs in coastal waters, as traditionally this application has only been applied to open-ocean, offshore waters. SSTs in the nearshore waters of Rottnest Island, Western Australia, were determined using in situ temperature loggers and remotely sensed satellite data. Initially the accuracy of the satellite sea …

Hydrogeological Study Of The Dongolocking Reserves, Dumbleyung, Western Australia, Ben Whitfield

Resource management technical reports

The aims of the hydrogeological study were to assess the characteristics of aquifers within the weathered zone, throughout the Dongolocking Reserves and in the surrounding farmland; provide baseline data on root zone salt store (EM38) and vertical distribution of stored salts (EM38) through the use of ground-based geophysical techniques; identify remnant bush at risk of salinisation; suggest management options to address any observed salinity problems; provide a groundwater monitoring network.

Post-Stagnation Behavior In The Upstream Regions Of Ice Stream C, West Antarctica, Stephen F. Price, R. A. Bindschadler, Christina L. Hulbe, Ian R. Joughin

Geology Faculty Publications and Presentations

The region where two active tributaries feed into the now stagnant Ice Stream C (ISC), West Antarctica, is thickening. In this region, we observe a correlation between faster ice flow (the tributaries) and elevated topography. We conclude that stagnation of ISC resulted in compression and thickening along the tributaries, eventually forming a "bulge" on the ice-sheet surface. Modern hydraulic potential gradients would divert basal meltwater from ISC to Ice Stream B (ISB). These gradients are primarily controlled by the bulge topography, and so likely formed subsequent to trunk stagnation. As such, we argue against "water piracy" as being the cause …

Sedimentary Cyclicity In Crp Drillcore, Victoria Land Basin, Antarctica, T. R. Naish, P. J. Barrett, G. B. Dunbar, K. J. Woolfe, A. G. Dunn, S. A. Henrys, M. Claps, R. D. Powell, Christopher R. Fielding

Department of Earth and Atmospheric Sciences: Faculty Publications

The upper 1200 m of pre-Pliocene sediment recovered by Cape Roberts Project (CRP) drilling off the Victoria Land coast of Antarctica between 1997-1999 has been subdivided into 54 unconformity-bound stratigraphic sequences, spanning the period c. 32 to 17 Ma. The sequences are recognised on the basis of the cyclical vertical stacking of their constituent lithofacies, which are enclosed by erosion surfaces produced during the grounding of the advancing ice margin onto the sea floor. Each sequence represents deposition in a range of offshore shelf to coastal glacimarine sedimentary environments during oscillations in the ice margin across the Western Ross Sea …

South West Hydrological Information Package : Understanding And Managing Hydrological Issues On Agricultural Land In The South West Of Western Australia, Peter J. Tille, T W. Mathwin, Richard J. George Dr

Bulletins 4000 -

This manual reviews current knowledge of the hydrological issues that affect, or are affected by, agriculture in the catchments of the south west of Western Australia.

Wa Soil Erosion Under Investigation, George Richard Dr

Journal of the Department of Agriculture, Western Australia, Series 4

A survey of soil erosion at 70 sites throughout Western Australia, recently completed as a part of a National Reconnaissance Survey, has shown that erosion is occurring at an unsustainable rate. While still to be compiled into a national publication, Dr Richard George reports on the Western Australian results, and discusses options for management and further investigation.

Early Oligocene Siliceous Microfossil Biostratigraphy Of Cape Roberts Project Core Crp-3, Victoria Land Basin, Antarctica, David M. Harwood, S. M. Bohaty

Department of Earth and Atmospheric Sciences: Faculty Publications

Early Oligocene siliceous microfossils were recovered in the upper c. 193 m of the CRP-3 drillcore. Although abundance and preservation are highly variable through this section, approximately 130 siliceous microfossil taxa were identified, including diatoms, silicoflagellates, ebridians, chrysophycean cysts, and endoskeletal dinoflagellates. Well-preserved and abundant assemblages characterize samples in the upper c. 70 m and indicate deposition in a coastal setting with water depths between 50 and 200 m. Abundance fluctuations over narrow intervals in the upper c. 70 mbsf are interpreted to reflect environmental changes that were either conducive or deleterious to growth and preservation of siliceous microfossils. Only …

Saunders County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Central Us Earthquake Catalog For Hazard Maps Of Memphis, Tennessee, Russell L. Wheeler, Charles S. Mueller

United States Geological Survey: Staff Publications

An updated version of the catalog that was used for the current national probabilistic seismic-hazard maps would suffice for preduction of large-scale hazard maps of the Memphis urban area. Deaggregation maps provide guidance as to the area that a catalog for calculating Memphis hazard should cover. For the future, the Nuttli and local netword catalogs could be examined for earthquakes nor presenly included in the cataloge. Additional work on the aftershock removal might reduce hazard uncertainty. Graphs of decadal and annual earthquake rates suggest completeness at and above magnitude 3 for the last three or four decades. Any additional work …

Weathering Crust Processes On Melting Glacier Ice (Alberta, Canada), Corinne Joanne Schuster

Theses and Dissertations (Comprehensive)

This thesis examines the relationship between the energy balance and hydrology of a glacier at the ice surface interface during the melt season. Experimental sub-catchments were established on the ablation area of the Peyto Glacier, Alberta, Canada, during the summers of 1994, 1995 and 1997. These sub-catchments were equipped with meteorological and hydrological instrumentation to examine relationships in the surface layer. Specifically, the development of a phenomenon known as the weathering crust is followed by examining the ratio between potential surface lowering (calculated from energy available for melt) and actual surface lowering (as measured in the field). This enables an …

Application Of Orthogonal Polynomials To Geostatistics, Ainslie Chapman

Theses : Honours

Geostatistics is a field of study that deals with spatially dependent attributes. As information regarding these attributes is usually only available at sample locations, estimates must be made at unsampled locations. Sample data are usually measured on point support within the study region, however in reality decisions are based on small blocks and not on points. A change-of-support model is required to obtain the theoretical distribution of block values given the sample point values. Estimates arc then made for a collection of blocks, referred to as a panel. Kriging is a generic term adopted by geostatisticians for a family of …

Data Report: Carbon Isotopic Composition Of Dissolved Co2, Co2 Gas, And Methane, Blake-Bahama Ridge And Northeast Bermuda Rise, Odp Leg 172, Walter S. Borowski, Namik Cagatay, Y Tournois, Charles K. Paull

EKU Faculty and Staff Scholarship

Carbon isotopic data of interstitial dissolved CO2 (ΣCO2), CO2 gas, and methane show that a variety of microbial diagenetic processes produce the observed isotopic trends. Anaerobic methane oxidation (AMO) is an important process near the sulfate-methane interface (SMI) that strongly influences the isotopic composition of ΣCO2 in the sulfate reduction and upper methanogenic zones, which in turn impacts methane isotopic composition. Dissolved CO2 and methane are maximally depleted in 3C near the SMI, where C values are as light as –31.8‰ and –101‰ PDB for ΣCO2 and methane, respectively. CO2 reduction links the CO2 and methane pools in the methanogenic …

Concrete Roughness Characterization Using Laser Profilometry For Fiber-Reinforced Polymer Sheet Application, Norbert H. Maerz, Poornima Chepur, John J. Myers, Justin Linz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The failure of a reinforced concrete member strengthened with fiberreinforced polymer (FRP) laminates may be caused by crushing of concrete, rupture of FRP laminates, or delamination of the FRP sheet. Therefore, the effectiveness and failure mode of FRP sheets applied to beams and columns is related to the degree of adhesion of the epoxy to the concrete surface. When a peeling or delamination failure can be avoided, a more effective engagement of the FRP sheet occurs, which results in more efficient use of the material. One of the principal factors affecting the bond behavior between the concrete and epoxy is …

Uptake Of Dissolved Organic Selenides By Marine Phytoplankton, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter

OES Faculty Publications

Se is present in multiple oxidation states in nature, each of which has unique chemical and biological reactivities. As a consequence, the rate of Se incorporation into food webs or its role as either a limiting nutrient or a toxic substance is a function of complex biogeochemistry. In particular, little is understood about the accumulation of dissolved organic selenides by phyto- or bacterioplankton. We assessed the bioavailability of dissolved organic selenides to marine and estuarine phytoplankton by presenting various algal species with filtered lysates of the diatom, Thalassiosira pseudonana, grown on media amended with radiolabeled selenite (⁷⁵Se[IV]). …

Control Of Phytoplankton Growth By Iron Supply And Irradiance In The Subantarctic Southern Ocean: Experimental Results From The Saz Project, P. W. Boyd, A. C. Crossley, G. R. Ditullio, F. B. Griffiths, D. A. Hutchins, B. Queguiner, Peter N. Sedwick, T. W. Trull

OES Faculty Publications

The influence of irradiance and Fe supply on phytoplankton processes was studied, north (47°S, 142°E) and south (54°S, 142°E) of the Subantarctic Front in austral autumn (March 1998). At both sites, resident cells exhibited nutrient stress (F_v/F_m 0 at 47°S and 9% I₀ at 54°S because of MLDs of 40 (47°S) and 90 m (54°S), when these stations were occupied. The greater MLD at 54°S is reflected by tenfold higher cellular chlorophyll a levels in the resident phytoplankton. In the 47°S experiment, chlorophyll a levels increased to >1 μg/L^-1 only in the high-Fe treatments, regardless …

Control Of Phytoplankton Growth By Iron And Silicic Acid Availability In The Subantarctic Ocean: Experimental Results From The Saz Project, D. A. Hutchins, Peter N. Sedwick, G. R. Ditullio, P. W. Boyd, B. Queguiner, F. B. Griffiths, C. Crossley

OES Faculty Publications

Subantarctic Southern Ocean surface waters in the austral summer and autumn are characterized by high concentrations of nitrate and phosphate but low concentrations of dissolved iron (Fe, similar to0.05 nM) and silicic acid (Si, <1 muM). During the Subantarctic Zone AU9706 cruise in March 1998 we investigated the relative importance of Fe and Si in controlling phytoplankton growth and species composition at a station within the subantarctic water mass (46.8degreesS, 142degreesE) using shipboard bottle incubation experiments. Treatments included unamended controls; 1.9 nM added iron (+Fe); 9 muM added silicic acid (+Si); and 1.9 nM addediron plus 9 muM added silicic acid (+Fe+Si). We followed a detailed set of biological and biogeochemical parameters over 8 days. Fe added alone clearly increased community growth rates and nitrate drawdown and altered algal community composition relative to control treatments. Surprisingly, small, lightly silicified pennate diatoms grew when Fe was added either with or without Si, despite the extremely low ambient silicic acid concentrations. Pigment analyses suggest that lightly silicified chrysophytes (type 4 haptophytes) may have preferentially responded to Si added either with or without Fe. However, for many of the parameters measured the +Fe+Si treatments showed large increases relative to both the +Fe and +Si treatments. Our results suggest that iron is the proximate limiting nutrient for chlorophyll production, photosynthetic efficiency, nitrate drawdown, and diatom growth, but that Si also exerts considerable control over algal growth and species composition. Both nutrients together are needed to elicit a maximum growth response, suggesting that both Fe and Si play important roles in structuring the subantarctic phytoplankton community.

Iron In East Antarctic Snow: Implications For Atmospheric Iron Deposition And Algal Production In Antarctic Waters, Ross Edwards, Peter N. Sedwick

OES Faculty Publications

To evaluate the deposition and solubility of aerosol iron in the Antarctic seasonal sea ice zone (SSIZ), iron was measured in snow samples collected from three areas in the SSIZ (Prydz Bay, Dumont d'Urville Sea and Ross Sea) and one continental area (Princess Elizabeth Land) of East Antarctica. Concentrations of total-dissolvable iron (that soluble at pH ~2) ranged from 20-2950 pg g^-1, with the lowest concentrations measured in snow from the Dumont d'Urville Sea. Using estimates of snow accumulation rates, we calculate atmospheric iron deposition fluxes of 0.017-0.11 mg m^-2 yr^-1(0.30-2.0 μmol m^-2 yr …

Effects Of Iron, Silicate, And Light On Dimethylsulfoniopropionate Production In The Australian Subantarctic Zone, G. R. Ditullio, P. N. Sedwick, D. R. Jones, P. W. Boyd, A. C. Crossley, D. A. Hutchins

OES Faculty Publications

Shipboard bottle incubation experiments were performed to investigate the effects of iron, light, and silicate on algal production of particulate dimethylsulfoniopropionate (DMSP_p) in the Subantarctic Zone (SAZ) south of Tasmania during March 1998. Iron enrichment resulted in threefold to ninefold increases in DMSP_p concentrations relative to control treatments, following 7 and 8-day incubation experiments. Additions of Fe and Si preferentially stimulated the growth of lightly-silicified pennate diatoms and siliceous haptophytes, respectively, to which we attribute the increased DMSP_p production in the incubation bottles. Both of these algal groups were previously believed to be low DMSP_{p …}

Introduction To Special Section: Saz Project, T. W. Trull, Peter N. Sedwick, F. B. Griffiths, S. R. Rintoul

OES Faculty Publications

Oceanographic processes in the subantarctic region contribute crucially to the phys. and biogeochemical aspects of the global climate system. To explore and quantify these contributions, the Antarctic Cooperative Research Center organized the SAZ Project, a multidisciplinary, multiship study carried out south of Australia in the austral summer of 1997-1998. We present an overview of the SAZ Project and some of its major results.

Holocene Sediment Records From The Continental Shelf Of Mac. Robertson Land, East Antarctica, Peter N. Sedwick, Peter T. Harris, Lisette G. Robertson, Gary M. Mcmurtry, Maximilian D. Cremer, Philip Robinson

OES Faculty Publications

Geochemical records are presented for five sediment cores from basins on the continental shelf of Mac. Robertson Land, East Antarctica. The cores contain 2-4 m thick sequences of hemipelagic, siliceous mud and ooze (SMO) deposited under seasonally open marine conditions. The inner and middle shelf SMO sequences are massive dark olive green material, whereas the outer shelf SMO sequences are dark olive material interspersed with light olive green layers similar to1-10 cm thick. The biogenic material is dominated by marine diatoms including Fragilariopsis curta, Fragilariopsis cylindrus, and Chaetoceros spp. in the dark-colored SMO and Corethron criophilum in the …

An Analysis Of A Radio Frequency Sensor As A Means To Remotely Sense Selected Surface Topographies In An Agriculture Environment, Barry Michael Alexia

Dissertations and Theses @ UNI

Remote sensing is the science and art of obtaining information about an object, area or phenomenon through the analysis of data acquired by a device that is not in contact with the object, area, or phenomenon under investigation. The remotely sensed data can be of many forms, including variations in force distribution, acoustic wave distribution, or electromagnetic energy distribution.Information thus acquired can be used for observing,monitoring, and studying planetary surfaces and environments.

Because there are many ways to acquire data about targets of interest, there are many types of remote sensors that can be used, including visible, infrared, and active …

Ichnology Of Holocene Carbonate Eolianites Of The Bahamas, H. Allen Curran, Brian White

Geosciences: Faculty Publications

No abstract provided.