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Regulation Of Algal Blooms In Antarctic Shelf Waters By The Release Of Iron From Melting Sea Ice, Peter N. Sedwick, Giacomo R. Ditullio Jan 1997

Regulation Of Algal Blooms In Antarctic Shelf Waters By The Release Of Iron From Melting Sea Ice, Peter N. Sedwick, Giacomo R. Ditullio

OES Faculty Publications

During summer 1995-96, we measured iron in the water column and conducted iron-enrichment bottle-incubation experiments at a station in the central Ross Sea (76°30'S, 170°40'W), first, in the presence of melting sea ice, and 17 days later, in ice-free conditions. We observed a striking temporal change in mixed-layer dissolved iron concentrations at this station, from 0.72-2.3 nM with sea ice present, to 0.16-0.17 nM in ice-free conditions. These changes were accompanied doubling of algal (diatom) biomass. Our incubation experiments suggest that conditions were iron-replete in the presence of sea ice, and iron-deficient in the absence of sea ice. We surmise …


Geology Newsletter- 1996, Department Of Geology Dec 1996

Geology Newsletter- 1996, Department Of Geology

Geological and Environmental Sciences News

Vol. 1, No. 21

  • Faculty News
  • Alumni/ Friends/ Former Faculty Notes
  • Geology Development
  • Donations
  • Scholarship Donations


Histomorphological Responses Of Red Shiner (Cyprinella Lutrensis) To Atrazine, Terbufos, And Their Mixture, Ibrahim A. Messaad Dec 1996

Histomorphological Responses Of Red Shiner (Cyprinella Lutrensis) To Atrazine, Terbufos, And Their Mixture, Ibrahim A. Messaad

School of Natural Resources: Dissertations, Theses, and Student Research

Alterations of normal histomorphology of fish tissues, behavior, and thermal tolerance are recognized by environmental toxicologists and fish biologists as powerful tools indicating diverse biochemical and physiological changes. Toxicity of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine), terbufos (S-(((1,1-dimethyl-ethyl)thio)methyl)O,O-diethyl phosphorodithioate), and their mixture to red shiner (Cyprinella lutrensis) at 23$\sp\circ$C and 30$\sp\circ$C was investigated in 14-d bioassays after 14-d acclimation. During the bioassays, fish behavior, indications of toxicosis, and external anomalies were observed. After the bioassays, the critical thermal maximum (CTM) was determined. Fish also were preserved for examinations of gill, liver, and kidney tissues using scanning electron microscopy (SEM) and light microscopy (LM). SEM …


A Depositional Analysis Of The Wymer Site, Berrien County, Michigan And Its Relationship To Post-Glacial Lake Levels In The Lake Michigan Basin, Kevin A. Kincare Dec 1996

A Depositional Analysis Of The Wymer Site, Berrien County, Michigan And Its Relationship To Post-Glacial Lake Levels In The Lake Michigan Basin, Kevin A. Kincare

Masters Theses

The Wymer site is an archeological site on the St. Joseph River floodplain 1.5 miles north of Berrien Springs, Michigan. Early and Middle Archaic cultural phases were found at the site. These sites are unusual in that their occurrence corresponds to low lake levels associated with Lake Chippewa and were assumed to occupy the now submerged shoreline areas.

A site evaluation was undertaken to examine the types of sediments and depositional structures. Trenches, grainsize analysis, 14C samples and valley topography were used to determine that the site was a point bar situated on a terrace above the modern floodplain. …


The Effects Of Wet Meadow Fragmentation On Grassland Birds, Christopher J. Helzer Dec 1996

The Effects Of Wet Meadow Fragmentation On Grassland Birds, Christopher J. Helzer

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


The Geology And Structures In The Northern Hiko Range, Lincoln County, Nevada, Douglas D. Switzer Dec 1996

The Geology And Structures In The Northern Hiko Range, Lincoln County, Nevada, Douglas D. Switzer

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the northern Hiko Range, extension occurred in four temporally distinct episodes during the Cenozoic. The extensional events are (1) prevolcanic (> 27.31 ± 0. 03 Ma), (2) syn-volcanic (between 22.78 ± 0,03 and 18.5 ± 0.4 Ma), (3) Tertiary(?) post-volcanic ( < 14.7 ± 0.4 Ma), and ( 4) Pliocene(?) - Quaternary. Four fault sets are delineated based on orientation and cross-cutting relationships: (I) northeast- to northwest-striking moderately dipping prevolcanic faults, (2) east-west striking, steeply-dipping syn-volcanic faults, (3) east-west- and east-northeast-striking, steeply dipping Tertiary(?) post-volcanic faults, and (4) generally north-striking steeply dipping Pliocene (?) - Quaternary faults.

Prevolcanic faults in the northern Hiko Range are interpreted to be footwall faults to an Oligocene age extensional system. These faults increase the area affected by Oligocene extension and support existing evidence that suggests this event is widespread.

A tectonomagmatic rift model has been proposed to explain synvolcanic extension during the Tertiary in the northern Basin and Range …


Hydrogeology And Stable Isotope Investigations Of A Landfill Impacted Site In Southwest Michigan, Eliot Anong Atekwana Dec 1996

Hydrogeology And Stable Isotope Investigations Of A Landfill Impacted Site In Southwest Michigan, Eliot Anong Atekwana

Dissertations

The Cork Street landfill in the City of Kalamazoo is unlined and constructed in glacial drift material. Although water quality in some of the landfill monitoring wells is poor, the degree of the landfill’s influence to groundwater, wetlands and Davis Creek located downgradient of the landfill is unknown. The objective of this study is to evaluate the degree of the landfill’s impact in this region through hydrologic and stable isotope analysis.

Site characterization using geophysical surveys and specific conductance measurements indicates highly conductive shallow groundwater probably attributable to groundwater contamination. Hydrologic evaluation of this region shows that groundwater flows towards …


The Use Of Bauxite Residue As A Soil Amendment In The Peel-Harvey Coastal Plain Catchment - Report On Results Of 1995 Environmental Monitoring Program, Mark Rivers Nov 1996

The Use Of Bauxite Residue As A Soil Amendment In The Peel-Harvey Coastal Plain Catchment - Report On Results Of 1995 Environmental Monitoring Program, Mark Rivers

Natural resources published reports

This report was submitted in accordance with the recommendations of the Environmental Protection Authority (EPA) who have stated that a monitoring program shall be undertaken by Agriculture Western Australia within six months of the widespread use of bauxite residue as a soil amendment. Although this widespread use of bauxite residue has not yet formally commenced, pre-emptive monitoring has been undertaken in order to gain some understanding of the general environmental characteristics of the Peel-Harvey catchment and, in particular, the characteristics and quality of the water flowing through the catchment.

It represents the second annual report submitted to the EPA describing …


Western Australian Salinity Action Plan, Agriculture Western Australia, Department Of Conservation And Land Management, Department Of Environmental Protection, Water And Rivers Commission Nov 1996

Western Australian Salinity Action Plan, Agriculture Western Australia, Department Of Conservation And Land Management, Department Of Environmental Protection, Water And Rivers Commission

Natural resources published reports

Salinity is one of the State's most critical environmental problems, threatening major economic and social consequences. It is preventable and, in the long term, reversible. Complete elimination is not realistic, but we can dramatically reduce its impact.

Salinity is caused by replacing deep-rooted native plants with shallow-rooted crops and pastures. More rainfall passed below the root zone and accumulates as groundwater so that watertables rise. The groundwater mobilises natural salts in the soil as it rises and carries them towards the surface, eventually degrading land and streams.


Cycle Symmetry And Its Causes, Cisco Group (Virgilian And Wolfcampian), Texas, Wan Yang Nov 1996

Cycle Symmetry And Its Causes, Cisco Group (Virgilian And Wolfcampian), Texas, Wan Yang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

181 transgressive-regressive cycles composed of nonmarine and marine carbonate and siliciclastic rocks of the Cisco Group on the Eastern Shelf, Texas, display complex characteristics at both hemicycle and full-cycle scales. They are delineated on the basis of successive changes of depositional environments, stratal boundary relations, and stratigraphic position. Transgressive and regressive stratigraphic environment gradients are defined as the magnitude of environmental shift divided by thickness for each hemicycle. They indicate the rates of lateral environmental shifts during transgression and regression. Cycle symmetry index is defined as the ratio between transgressive and regressive stratigraphic environment gradients. It provides a measure of …


Earth News, Fall 1996, Department Of Earth Science, University Of Northern Iowa. Oct 1996

Earth News, Fall 1996, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- News from the Earth Science Staff
--- Profile: Ken De Nault
--- Earth Science Majors
--- Sigma Gamma Epsilon - Gamma Sigma Chapter
--- Gifts to the Department of Earth Science
--- 1996 Scholarships and Award Recipients
--- Student Research Presentations
--- 1996 Earth Science Graduates
--- Special Alumni Newsetter Profile - Lee Potter
--- Earth Science Alumni Notes


Impact Of Groundwater Contamination In East Multnomah County On The Interlachen Community, Scott A. Wells, Shuguang Li, Marvin Beeson, Michael L. Cummings, Richard Pratt, Robert Leslie Annear, Karann Brandt Oct 1996

Impact Of Groundwater Contamination In East Multnomah County On The Interlachen Community, Scott A. Wells, Shuguang Li, Marvin Beeson, Michael L. Cummings, Richard Pratt, Robert Leslie Annear, Karann Brandt

Civil and Environmental Engineering Faculty Publications and Presentations

The Friends of Blue and Fairview Lake through the Environmental Protection Agency (EPA) Technical Assistance Grant (TAG) program contracted with Portland State University faculty and staff to provide an independent review of the groundwater contamination problem at the Boeing-Cascade site in East Multnomah County. An independent consultant, Karann Brandt, of PRC Environmental Management, Inc., was also assisting the panel with the review.

The region of groundwater contamination is a 2.5 square mile region bounded by NE Halsey Blvd. to the Columbia River and NE 178th to NE 223rd (see Figure 1). The groundwater contamination is primarily of volatile organic compounds …


Depositional Environment And Sequence Stratigraphic Interpretation Of Miocene St. Marys Formation, Calvert County, Maryland, John J. Blandin Oct 1996

Depositional Environment And Sequence Stratigraphic Interpretation Of Miocene St. Marys Formation, Calvert County, Maryland, John J. Blandin

OES Theses and Dissertations

The Miocene St. Marys Formation at Calvert Cliffs, Maryland is divided into four depositional packages made up of marine fades representing shallow shelf through intertidal conditions. These depositional packages are separated by five laterally persistent surfaces and were defined based on detailed depositional fades analysis of 24 measured sections, averaging 17 meters thick. These four packages make up two marine sequences, stratigraphic units bound above and below by surfaces of sea level fall. The lower sequence is composed of a single depositional package, while the upper sequence is composed of three upward-shallowing depositional packages (i.e. para-sequences). A fifth depositional package …


Managing Pastures For Long-Term Prosperity, Hugh Pringle, Jenny Riches Sep 1996

Managing Pastures For Long-Term Prosperity, Hugh Pringle, Jenny Riches

Natural resources published reports

A Workshop held by the Sandstone Land Conservation District Committee

Lake Mason Station

April 1994

A workshop hosted by Sandstone Land Conservation District Committee (LCDC) was held at Lake Mason station on 28 April 1994. This workshop was based on two previous workshops hosted by the Kalgoorlie and north-eastern Goldfields LCDCs in May 1991 (Pringle et al. 1992). The success of the earlier workshops prompted the rangeland survey team in association with the Sandstone LCDC and the Kalgoorlie District Office of Agriculture Western Australia to initiate the project.

The aims were to provide a summary of local wisdom regarding pasture …


Localized Amplification Of Seismic Waves And Correlation With Damage Due To The Northridge Earthquake: Evidence For Focusing In Santa Monica, Stephen S. Gao, Kelly H. Liu, Paul M. Davis, Leon Knopoff Sep 1996

Localized Amplification Of Seismic Waves And Correlation With Damage Due To The Northridge Earthquake: Evidence For Focusing In Santa Monica, Stephen S. Gao, Kelly H. Liu, Paul M. Davis, Leon Knopoff

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The analysis of seismograms from 32 aftershocks recorded by 98 seismic stations installed after the Northridge earthquake in the San Fernando Valley, the Santa Monica Mountains, and Santa Monica, California, indicates that the enhanced damage in Santa Monica is explained in the main by focusing due to a lens structure at a depth of several kilometers beneath the surface and having a finite lateral extent. The diagnosis was made from the observation of late-arriving S phases with large amplitudes, localized in the zones of large damage. The azimuths and angles of incidence of the seismic rays that give rise to …


Propagation Of Juniperus For Conservation Plantings In The Great Plains, Scott Allen Lee Aug 1996

Propagation Of Juniperus For Conservation Plantings In The Great Plains, Scott Allen Lee

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Bulletin 4329 - Environmental Hazards Of Farming In Western Australia, Greg Hamilton, Ian Foster, Philip M. Goulding Aug 1996

Bulletin 4329 - Environmental Hazards Of Farming In Western Australia, Greg Hamilton, Ian Foster, Philip M. Goulding

Bulletins 4000 -

This Bulletin is one of a series on crop establishment practices which minimise soil disturbance and improve stubble retention. In partnership with primary producers, Agriculture Western Australia 1s focussed on improved and profitable farming which conserves or improves the quality of the State's soil resources.

Agricultural land in Western Australia is naturally fragile and susceptible to degradation. Salinity and wind erosion are the most visible and significant forms of degradation, but all forms are present over large areas of agricultural land (House of Representatives Enquiry into Land Degradation in Western Australia, 1988).

The fragility of Western Australia's soils has been …


The Effects Of The Kalamazoo Station No. 4 On The Nearby Kleinstuck Nature Preserve, Robert J. Buechler Aug 1996

The Effects Of The Kalamazoo Station No. 4 On The Nearby Kleinstuck Nature Preserve, Robert J. Buechler

Masters Theses

This was a 15 month study that studied the effects of Kalamazoos' Municipal Pumping Station No. 4 on the Kleinstuck Nature Preserve. The preserve is about a quarter of a mile in the up gradient direction of Station No. 4. This study demonstrates that there is a direct correlation between the pumping and the water levels at the preserve. Pumping records show that there is no correlation between precipitation and the water levels at the preserve.

There are other factors which exaggerate this effect. It has been found that the drain field at the Y.M.C.A. parking lot, the breaching of …


Simulation The Shift In Position Of Hinge Lines Between Two, Shallow, Flow-Through Lakes, Mohan J. Khisty Aug 1996

Simulation The Shift In Position Of Hinge Lines Between Two, Shallow, Flow-Through Lakes, Mohan J. Khisty

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Groundwater flow between two hypothetical, shallow, flow-through lakes was numerically simulated in steady state and transient conditions for two cases. In the first case the lakes are at identical surface water elevations and in the second case there is a small difference in surface water elevations between them. Simulation results from both cases indicate a direct relation between movement of hinge lines, which indicate changes in the direction of groundwater-lake seepage components, and the seasonal persistence and decline of a groundwater mound that exists between the two lakes. A comparison between steady-state simulation results for both cases indicates that a …


The Biology Of Alewife Alosa Pseudoharengus In Lake Ogallala, Nebraska, Eric A. Laux Aug 1996

The Biology Of Alewife Alosa Pseudoharengus In Lake Ogallala, Nebraska, Eric A. Laux

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Spatial And Temporal Variability In The Distribution Of Nitrate In An Agriculturally-Impacted Aquifer, Cass County, Michigan, Caroline Lovetere Aug 1996

Spatial And Temporal Variability In The Distribution Of Nitrate In An Agriculturally-Impacted Aquifer, Cass County, Michigan, Caroline Lovetere

Masters Theses

Ground-water sampling in a shallow unconfined aquifer within a predominantly agricultural area in southwestern Michigan indicated spatial and temporal variability in the distribution of nitrate. The unconfined aquifer, which is about 40 feet thick, consists of glacially-deposited sand and gravel with interbedded clay lenses and is separated from a lower semi-confined aquifer by a 3-to 26-feet-thick till layer.

The site of the study was a 47-acre agricultural field, characterized by corn and alfalfa hay production, to which hog manure and commercial fertilizers were frequently applied. The shallow water table and relatively permeable glacial sands in the vadose zone combined to …


Hydrostratigraphy And Allostratigraphy Of The Cenozoic Alluvium In The Northwestern Part Of Las Vegas Valley, Clark County, Nevada, David J. Donovan Aug 1996

Hydrostratigraphy And Allostratigraphy Of The Cenozoic Alluvium In The Northwestern Part Of Las Vegas Valley, Clark County, Nevada, David J. Donovan

UNLV Theses, Dissertations, Professional Papers, and Capstones

This investigation was conducted to determine the location, nature, and boundaries of the most permeable unit within the alluvial aquifer material in Las Vegas Valley. It was prompted by declines in specific capacity of about 90% at the Las Vegas Valley Water District's West Central Well Field. It was hypothesized that the decline in specific capacity resulted from dewatering of the most permeable interval of the alluvium. Lithologic descriptions from wells and aquifer test information were analyzed for geologic and hydrogeologic variability. New information, in the form of detailed unpublished lithologic and hydrologic information, was available from twenty water wells …


The Petrogenesis Of Andesites Produced During Regional Extension: Examples From The Northern Mccullough Range, Nv And Xitle Volcano, Mexico, Kelly Ann Boland Aug 1996

The Petrogenesis Of Andesites Produced During Regional Extension: Examples From The Northern Mccullough Range, Nv And Xitle Volcano, Mexico, Kelly Ann Boland

UNLV Theses, Dissertations, Professional Papers, and Capstones

Andesite dominated volcanic systems produced during regional crustal extension remain a relatively unexplored aspect of andesite petrogenesis. In the southern Basin and Range province, thick sections of andesite and basaltic andesite have been documented in areas including the Piute Range, California, the Eldorado Range, Nevada, and the McCullough Range, Nevada. The northern McCullough Range, located 20 miles south-southeast of Las Vegas, is an ideal place to study the petrogenesis of an andesite dominated system. This area contains a mid-Miocene stratocone composed mainly of a 1200 m thick section of andesite flows that formed synchronous with regional extension.

The northern McCullough …


Quantification Of Extraterrestrial Lava Flow Effusion Rates Through Laboratory Simulations, Tracy K.P. Gregg, Jonathan H. Fink Jul 1996

Quantification Of Extraterrestrial Lava Flow Effusion Rates Through Laboratory Simulations, Tracy K.P. Gregg, Jonathan H. Fink

Geology Faculty Publications and Presentations

We have used carefully controlled laboratory simulations to develop a model which relates lava flow morphology to effusion rate and rheology. Through comparisons with measured and estimated eruption rates on Earth, this approach allows us to constrain eruptive styles and compositions of extraterrestrial lava flows. By applying this model to lava flows on the Moon, Mars and Venus, we have determined that all the common flow morphologies (domes, folds and levees) on these planets could have been produced by basalt-like or andesite-like lavas through either continuous or episodic emplacement. The presence of more evolved magma compositions on other planets is …


Application Of Permutations To Lossless Compression Of Multispectral Thematic Mapper Images, Ziya Arnavut, Sunil Narumalani Jul 1996

Application Of Permutations To Lossless Compression Of Multispectral Thematic Mapper Images, Ziya Arnavut, Sunil Narumalani

Department of Earth and Atmospheric Sciences: Faculty Publications

The goal of data compression is to find shorter representa- tions for any given data. In a data storage application, this is done in order to save storage space on an auxiliary device or, in the case of a communication scenario, to increase channel throughput. Because re- motely sensed data require tremendous amounts of transmission and storage space, it is essential to find good algorithms that utilize the spa- tial and spectral characteristics of these data to compress them. A new technique is presented that uses a spectral and spatial correlation to create orderly data for the compression of multispectral …


Correlation Of The Upper Ellensburg Formation With The Old Scab Mountain Eruptive Center, East-Central Cascade Range, Washington, Christopher Charles Humphrey Jul 1996

Correlation Of The Upper Ellensburg Formation With The Old Scab Mountain Eruptive Center, East-Central Cascade Range, Washington, Christopher Charles Humphrey

Dissertations and Theses

The Ellensburg Formation, preserved in the Nile basin 50 km northwest of Yakima, Washington, consists of a series of middle to late Miocene epiclastic and pyroclastic rock assemblages rich in porphyritic hornblende-biotite dacite. Geochemical, petrographic, and stratigraphic correlations indicate that Old Scab Mountain, a dacite porphyry intrusion, located at the western margin of the basin (lat. 46°53'30", long. 121°13'00"), is the probable source for much of the upper Ellensburg volcaniclastic material in the basin. The dacite intrusion exposed at Old Scab Mountain was emplaced at depths of 1 to 3 km and underlaid a now eroded volcanic edifice. This volcanic …


Swath Mapping On The Continental Shelf And Slope: The Eel River Basin, Northern California, John A. Goff, Larry A. Mayer, John E. Hughes Clarke, Lincoln F. Pratson Jul 1996

Swath Mapping On The Continental Shelf And Slope: The Eel River Basin, Northern California, John A. Goff, Larry A. Mayer, John E. Hughes Clarke, Lincoln F. Pratson

Affiliate Scholarship

First Paragraph

The STRATAFORM program sponsored by the Office of Naval Research (Nittrouer and Kravitz, 1996, this issue) seeks to understand how sedimentary processes lead to the formation of the stratigraphic sequences on continental margins. A central challenge facing this effort is to understand the transport of sediments in shore-parallel as well as shore-perpendicular directions• Multidimensionality is necessary to describe, for example, the accumulation of sediments from river inputs, the distribution of gullies and canyons on the slope, the meandering of channels, and the structure of slumps and slides.


Ua66/8/3 Annual Report, Wku Geography & Geology Jul 1996

Ua66/8/3 Annual Report, Wku Geography & Geology

WKU Administration Documents

Annual report created by and about WKU Geography & Geology.


Boundary Conditions For Convergent Radial Tracer Tests And Effect Of Well Bore Mixing Volume, Vitaly A. Zlotnik, John David Logan Jul 1996

Boundary Conditions For Convergent Radial Tracer Tests And Effect Of Well Bore Mixing Volume, Vitaly A. Zlotnik, John David Logan

Department of Earth and Atmospheric Sciences: Faculty Publications

Convergent radial flow tracer tests have a complex spatial nonaxial transport structure caused by the flow in the vicinity of the injection well and its finite mixing volume. The formulation of the boundary value problem, and especially the treatment of the boundary conditions at the injection well, is nontrivial. Hodgkinson and Lever [1983], Moench [1989, 1991], and Welty and Gelhar [1994] have developed different models and methods for the analysis of breakthrough curves in the extraction well. To extend interpretation techniques to breakthrough curves in the zone between injection and extraction wells, an analysis of conventional transport models is given, …


Marine Pore-Water Sulfate Profiles Indicate In Situ Methane Flux From Underlying Gas Hydrate, Walter S. Borowski, Charles K. Paull, William Ussler Iii Jul 1996

Marine Pore-Water Sulfate Profiles Indicate In Situ Methane Flux From Underlying Gas Hydrate, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

Marine pore-water sulfate profiles measured in piston cores are used to estimate methane flux toward the sea floor and to detect anomalous methane gradients within sediments overlying a major gas hydrate deposit at the Carolina Rise and Blake Ridge (U.S. Atlantic continental margin). Here, sulfate gradients are linear, implying that sulfate depletion is driven by methane flux from below, rather than by the flux of sedimentary organic matter from above. Thus, these linear sulfate gradients can be used to quantify and assess in situ methane flux, which is a function of the methane inventory below.