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Evolution Of Pliocene Climate Cyclicity At Hole 806b (5-2 Ma); Oxygen Isotope Record, Eystein Jansen, Larry A. Mayer, Jan Backman, R. Mark Leckie, Toshiaki Takayama Jan 1993

Evolution Of Pliocene Climate Cyclicity At Hole 806b (5-2 Ma); Oxygen Isotope Record, Eystein Jansen, Larry A. Mayer, Jan Backman, R. Mark Leckie, Toshiaki Takayama

Affiliate Scholarship

A detailed Pliocene oxygen isotope record from the Ontong Java Plateau, based on measurements of the surface-dwelling planktonic foraminifer Globigerinoides sacculifer, was produced for the period from 5 to 2 Ma. The record documents major long and short-term climate changes. The results show periods of enhanced ice volume at 4.6 to 4.3 Ma and after 2.85 Ma, a long-term warming trend from 4.1 to 3.7 Ma, and a distinct cooling trend that was initiated at 3.5 Ma and progressed through the initiation of large-scale Northern Hemisphere glaciation after 2.85 Ma (according to the time scale of Shackleton and others proposed …


Iceberg Severity Off The Canadian East Coast (An Analysis Of The 1991 Iceberg Season), Jerome Edward Salloum Jan 1993

Iceberg Severity Off The Canadian East Coast (An Analysis Of The 1991 Iceberg Season), Jerome Edward Salloum

Theses and Dissertations (Comprehensive)

The 1991 iceberg season on the Grand Banks was the second most severe on record. Over a 218-day period, a total of 2002 icebergs traversed latitude 48°N. Percentages of sightings involving medium and large icebergs greatly exceeded normal values. Thus, the season was mxtstanding, not only in terms of flux numbers, but in terms of total ice mass delivered. Assuming that this flux anomaly is the product of more efficient advection and less efficient ablation and notzsome sudden surge in upstream berg production, the study investigates various atmospheric and sea surface conditions as contributing factors to a near record iceberg …


Seasonal Hydrology And Geochemistry Of Two Small High Arctic Catchments, Axel Heiberg Island, Northwest Territories, Julia Boike Jan 1993

Seasonal Hydrology And Geochemistry Of Two Small High Arctic Catchments, Axel Heiberg Island, Northwest Territories, Julia Boike

Theses and Dissertations (Comprehensive)

This study examines hydrological and geochemical processes in a continuous permafrost setting in the Canadian High Arctic on Axel Heiberg Island (79°25 ' N; 90°45 ' W) with the following objective: to identify spatial and seasonal variation in hydrology and geochemistry of the East Inflow (EIF) and West Inflow (WIF) sub basins draining into Colour Lake and relate them to processes operating in the basins. Field work in the catchment was carried out between 20 May to 16 August 1991 and 23 July to 20 August 1992. Surface flow and suprapermafrost groundwater in the active layer were monitored to assess …


Glacial Deposits, Vol. 21, 1992-1993, Department Of Geography-Geology Jan 1993

Glacial Deposits, Vol. 21, 1992-1993, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


The Second Occurrence Of The Troglobic Shrimp Macrobrachium Microps Holthuis (Crustacea, Decapoda, Palaemonidae), In Samoa, Alexander J. Bruce, Thomas M. Iliffe Jan 1993

The Second Occurrence Of The Troglobic Shrimp Macrobrachium Microps Holthuis (Crustacea, Decapoda, Palaemonidae), In Samoa, Alexander J. Bruce, Thomas M. Iliffe

International Journal of Speleology

A single example of Macrobrachium from an anchialine lava tube un Upolu, Samoa, is described and illustrated. The specimen is referred to M. microps Holthuis, 1978, but shows some differences that may be of specific value, which are discussed. The troglobic species of Macrobrachium are reviewed.


Ground Water Flow And Water Resources Investigation Of The Auburn, Summers And Shakertown Springs Karst Ground Water Basins, Logan And Simpson Counties, Kentucky, William Howcroft Dec 1992

Ground Water Flow And Water Resources Investigation Of The Auburn, Summers And Shakertown Springs Karst Ground Water Basins, Logan And Simpson Counties, Kentucky, William Howcroft

Masters Theses & Specialist Projects

The City of Auburn is faced with a number of problems relating to its dependency on two karst springs, Auburn and Summers Springs, to meet its water requirements. Besides being extremely vulnerable to contamination, the springs often discharge and insufficient volume of water needed for public consumption and dilution of the City’s treated wastewater. Thus the City wishes to find an additional source of water and views nearby Shakertown Spring as a possibility. The study has three main objectives: 1) delineation of the Auburn, Summers, and Shakertown Springs ground water basins, 2) determination of the volume of available water at …


The Influence Of Alfalfa Root Structure On Plains Pocket Gopher Damage And Behavior, Bruce A. Jasch Dec 1992

The Influence Of Alfalfa Root Structure On Plains Pocket Gopher Damage And Behavior, Bruce A. Jasch

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

No abstract provided.


Gully Evolution In The Upper Delaware River Basin Northeastern Kansas, Iona L. Meyer Nov 1992

Gully Evolution In The Upper Delaware River Basin Northeastern Kansas, Iona L. Meyer

Student Work

A small gully network developed across a pasture in the Dissected Till Plain of northeastern Kansas was monitored for one year to assess gully evolution in non-loessial materials. The objectives of this investigation were to identify stable and unstable drainage elements within the gully network; identify zones of net erosion and deposition; estimate the volume of sediment removed or deposited during the monitoring period; determine rates of headcut advancement; determine processes that advance and widen gullies, and to determine the historic development of the gully network.

Portions of the gully network were measured after every rain event exceeding 1.5 cm …


Development Of Membrane Film Fiber Optic Based Sensors For The Remote Monitoring Of The Quality Of Surface And Groundwater, Leonidas G. Bachas Aug 1992

Development Of Membrane Film Fiber Optic Based Sensors For The Remote Monitoring Of The Quality Of Surface And Groundwater, Leonidas G. Bachas

KWRRI Research Reports

The objective of this study was the development of chromo- and fluoroionophores and their subsequent use in sensors capable of surface and groundwater monitoring. Several reagents (modified crown ethers and porphyrins) were synthesized based on principles of chemical recognition and used for metal and pH sensing. The modified crown ether reagents include a chromogenic or fluorogenic group. The selectivity of these reagents is controlled by the size of the crown ether ring and the type of the chromogenic or fluorogenic side-arm. In addition, a fluorogenic crown ether was synthesized that incorporates a fluorogenic side-arm and a perfluorinated carbon chain. The …


Evidence Of Regional Structural Controls On Vent Distribution: Springerville Volcanic Field, Arizona, Charles B. Connor, Christopher Condit, Larry S. Crumpler, Jayne C. Aubele Aug 1992

Evidence Of Regional Structural Controls On Vent Distribution: Springerville Volcanic Field, Arizona, Charles B. Connor, Christopher Condit, Larry S. Crumpler, Jayne C. Aubele

School of Geosciences Faculty and Staff Publications

Quantitative analysis of the geographic distribution of vents and comparison with regional structural, petrologic, and vent age data provide insight into the processes governing the emplacement of vents in the Springerville volcanic field, Arizona. A total of 409 vents in the Springerville volcanic field (SVF) have a mean distance to nearest neighbor vents of 955 m, a much closer spacing than is common in some platform‐type volcanic fields. Based upon a cluster analysis search radius parameter of 4500 m, these vents comprise seven geographic clusters, with only five outlying vents occurring in the entire field. Cinder cone clusters in the …


Gis Characterization Of Beaver Watershed, H. D. Scott, J. M. Mckimmey Jun 1992

Gis Characterization Of Beaver Watershed, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Beaver Reservoir watershed is located in Northwest Arkansas including portions of Madison, Washington, Benton, Carroll, Franklin and Crawford counties. This watershed is important to the Northwest Arkansas region because it supplies most of the drinking water for the major towns and cities, and several rural water systems. The watershed consists of 308,971 ha with elevations ranging from approximately 341 m to 731 m above mean sea level. It includes the Springfield Plateau and the Boston Mountains provinces within the Ozark Plateau physiographic region. There are approximately 581 km of streams, 532 km of shore line, and 3712 km of roads …


Ua66/8/3 Annual Report, Wku Geography & Geology Jun 1992

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

WKU Administration Documents

Annual report created by and about WKU Geography & Geology.


Measurement Of The Effects Of Food Preparation Activities On The Microclimate Of The Snowball Dining Room Area Of Mammoth Cave, Kelly Kaletsky Jun 1992

Measurement Of The Effects Of Food Preparation Activities On The Microclimate Of The Snowball Dining Room Area Of Mammoth Cave, Kelly Kaletsky

Masters Theses & Specialist Projects

The stability of Mammoth Cave’s microclimate has never undergone extensive investigation. The Snowball Dining Room area was chosen to measure the microclimate of the cave and to determine if food preparation, human presence and surface temperature variations alter this microclimate. Three portable weather stations containing a temperature / humidity probe, datalogger and microbarograph were placed in various locations along three passageways leading away from the dining room. Readings were taken 24 hours per day for four months. Plotting temperature readings in graph form show a correlation between temperature of the passageway and distance from the dining room.


Stable Isotope Composition Of Calcareous Paleosols And Ground-Water Cements From The Ogallala Group (Neogene), Western Nebraska, Leonard Robert Gardner, Robert F. Diffendal Jr., Douglas F. Williams May 1992

Stable Isotope Composition Of Calcareous Paleosols And Ground-Water Cements From The Ogallala Group (Neogene), Western Nebraska, Leonard Robert Gardner, Robert F. Diffendal Jr., Douglas F. Williams

Robert F. Diffendal, Jr., Publications

A preliminary survey has been made of the stable isotope composition of secondary carbonates in the Ogallala Group of western Nebraska. The purpose of the study was to ascertain whether the isotopic signatures of calcareous paleosols in the fine grained facies of the Ogallala and groundwater cements in gravel facies might provide a basis for stratigraphic correlation and/or paleoclimatic interpretation.

The groundwater cemented channel gravels are modestly depicted in IRO (δ18O = –10‰) as compared to calcareous paleo'sols (δ18O = –8.0 to –9.0‰). Gravels of different age, however, have essentially identical isotopic signatures. The isotopic variability …


A Climatology Of Transition Season Colorado Cyclones: 1961-1990, Gregory D. Bierly May 1992

A Climatology Of Transition Season Colorado Cyclones: 1961-1990, Gregory D. Bierly

All-Inclusive List of Electronic Theses and Dissertations

Colorado cyclones have been the subject of many meteorologic and climatologic investigations, but few studies have examined cyclone behavior with a specific focus on a comparison of the spring and fall transition seasons in the upper level westerlies. Periods of change in the number of planetary waves lead to a rearrangement of the longwave pattern in the westerlies and an increased frequency of troughs in the southwestern United States. Short wave disturbances andjor jet maximum moving through the long wave pattern create the potential for Colorado cyclogenetic events and also increasing the frequency of severe weather resultant from these events. …


The Paleoecology And Geomorphology Of Holocene Deposits Of The Southern Malad River, Box Elder County, Utah, Ann Schaffer Elder May 1992

The Paleoecology And Geomorphology Of Holocene Deposits Of The Southern Malad River, Box Elder County, Utah, Ann Schaffer Elder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Widespread Lake Bonneville sediments have been modified by river aggradation and degradation associated with Holocene fluctuations in the Great Salt Lake. Exposures of exceptionally abundant and well-preserved molluscan deposits in the Bear River Valley, Utah, allow detailed paleoenvironmental reconstruction of Holocene environments. The exposed basal unit consists of largely unfossiliferous deltaic silts and clays deposited during Lake Bonneville time (roughly 11,000 - 13,000 yr B. P.). An unconformity representing at least 2000 yr separates the deltaic material from overlying highly fossiliferous stream sands. Eight species of molluscs, comprising a single community, occupied this low energy stream environment at 7690 ± …


Seabeam And Seismic Reflection Surveys On The Ontong Java Plateau, Larry A. Mayer, Tom H. Shipley, Edward L. Winterer, David Mosher, Rick A. Hagen Jan 1992

Seabeam And Seismic Reflection Surveys On The Ontong Java Plateau, Larry A. Mayer, Tom H. Shipley, Edward L. Winterer, David Mosher, Rick A. Hagen

Affiliate Scholarship

No abstract provided.


Natural And Technological Disasters: Causes, Effects And Preventive Measures, Nazrul I. Khandaker Jan 1992

Natural And Technological Disasters: Causes, Effects And Preventive Measures, Nazrul I. Khandaker

Publications and Research

No abstract provided.


Investigation Of Hydrometeorological Relationships, Pasu Glacier Basin, Northern Pakistan, Bob Boyce Jan 1992

Investigation Of Hydrometeorological Relationships, Pasu Glacier Basin, Northern Pakistan, Bob Boyce

Theses and Dissertations (Comprehensive)

Records of air temperature, global radiation and discharge from the Pasu Glacier basin in the Upper Indus River Basin have been examined with a view to developing a modest understanding of the simple physically based processes in action within this globally extreme mountainous region. Some glaciological data are also reported but in a preliminary manner. Relationships between air temperature characteristics, global radiation and discharge were investigated using correlation techniques. Daily average air temperatures recorded at the highest meteorological station, Parundas (4200m), provide the strongest degree of association with discharge. The data shows that this highly glacierised Karakoram basin exhibits similar …


Ages Of The Whitewater And Fairhaven Tills In Southwestern Ohio And Southeastern Indiana, Barry B. Miller, William D. Mccoy, William J. Wayne, C. Scott Brockman Jan 1992

Ages Of The Whitewater And Fairhaven Tills In Southwestern Ohio And Southeastern Indiana, Barry B. Miller, William D. Mccoy, William J. Wayne, C. Scott Brockman

Department of Earth and Atmospheric Sciences: Faculty Publications

Alloisoleucine/isoleucine (aIle/Ile) ratios obtained from fossil mollusc shells collected at localities in southwestern Ohio and southeastern Indiana, where they occur in silt beds associated with the Whitewater and Fairhaven tills, indicate a pre-Wisconsinan age for these tills, which had previously been thought to be early or middle Wisconsinan.

The aIle/Ile ratios in shells from beneath the buried soil (Sidney soil) and till exposed near Sidney, Ohio, are most similar to values in shells obtained from Illinoian sediments at Clough Creek in Hamilton County, Ohio; Mechanicsburg southwest, Illinois; and Trousdale Mine in Vermillion Co., Indiana. The first well-developed weathering profile in …


The Role Of The Vadose Zone In The Generation Of Runoff From A Headwater Basin In The Canadian Shield, Robert Alex Maclean Jan 1992

The Role Of The Vadose Zone In The Generation Of Runoff From A Headwater Basin In The Canadian Shield, Robert Alex Maclean

Theses and Dissertations (Comprehensive)

Hydrological processes occurring within the vadose zone, especially in heterogeneous soils and tills typical of the Canadian shield, are not well understood. This research investigates the importance of the vadose zone in a small headwater basin (Harp 4-21) in the Canadian shield with respect to the generation of stream runoff quantity and quality during episodic rainfall and snowmelt events. The study focused specifically on: firstly the effect of variable antecedent moisture conditions on water-table and stream response, secondly, the significance of the stored vadose water in water extracted from a rising water-table, and thirdly the significance of preferential flowpathways in …


The First Documentation Of A Lower Middle Pennsylvanian Upland Flora From The Eastern Margin Of The Eastern Interior Basin (Illinois Basin), Vicki J. Comer Jan 1992

The First Documentation Of A Lower Middle Pennsylvanian Upland Flora From The Eastern Margin Of The Eastern Interior Basin (Illinois Basin), Vicki J. Comer

Masters Theses

The primary objective of this study is to reconstruct the paleofloristics of an unnamed shale of lower Middle Pennsylvanian age. The shale is periodically exposed in the highwall of the Ashboro Pit, Log Cabin Coal Company, Clay County, Indiana. This will be the first upland fossil flora to be described from the eastern margin of the Eastern Interior Basin (Illinois Basin). The gray shale containing the upland flora lies directly above the Upper Block Coal (SW 1/4, SE 1/4, sec. 17, T. 11N., R. 6W.)

Two collections, collected on three different occasions were made available for analysis: Smithsonian Natural …


A Paleoenvironmental Analysis Based On Ostracode Assemblages From The Late Pliocene Tuapaktushak And Middle Pleistocene Karmuk Members Of The Gubik Formation Of The Arctic Coastal Plain, Western Alaska, D. E. Loehrke Jan 1992

A Paleoenvironmental Analysis Based On Ostracode Assemblages From The Late Pliocene Tuapaktushak And Middle Pleistocene Karmuk Members Of The Gubik Formation Of The Arctic Coastal Plain, Western Alaska, D. E. Loehrke

OES Theses and Dissertations

This study records and analyzes ostracode assemblages recovered from sediments assigned to the Late Pliocene Tuapaktushak and Middle Pleistocene Karmuk members of the Gubik Formation in the Skull Cliff area of the Arctic Coastal Plain in western Alaska. Forty-three species were identified from 47 samples (25 from the Tuapaktushak Member and 23 from the Karmuk Member). Samples were grouped by Q-mode cluster analysis and by member assignment for the purpose of analysis.

Paleoenvironmental analyses of ostracode assemblages representative of each cluster suggest all samples, regardless of cluster membership, were deposited in similar marine environments where water depths were in the …


River Channel Stability And The Implications For Fish Habitat, John T. Beebe Jan 1992

River Channel Stability And The Implications For Fish Habitat, John T. Beebe

Theses and Dissertations (Comprehensive)

The purpose of this project was to investigate various aspects of river channel stability as they relate to fish habitat. Two headwater creeks of the Credit River system, Black and Silver Creeks, and their confluent stream, the West Credit River in Southern Ontario were used in the study. Thirty-five cross-sections were established and revisited during four flow regimes, summer base flow, fall secondary peak flow, spring melt-high flow and post-spring high flow. Measurements of width, depth and temperature were taken at these times. Water samples were taken for determination of suspended sediment concentration. Channel stability was investigated in relation to …


Hydrologic Investigations Of Meltwaters Draining Gornergletscher And Findelengletscher, Switzerland Using Hydrochemistry And Isotopic Analyses, Robert A. Metcalfe Jan 1992

Hydrologic Investigations Of Meltwaters Draining Gornergletscher And Findelengletscher, Switzerland Using Hydrochemistry And Isotopic Analyses, Robert A. Metcalfe

Theses and Dissertations (Comprehensive)

The purpose of this thesis is to investigate the hydrological dynamics of Gornerglestcher and Findelengletscher, Switzerland by performing hydrochemical analyses on the bulk runoff exiting the portal of these two alpine glaciers. The hydrochemical analyses utilized electrical conductivity, as a surrogate for total dissolved solids, to determine the flow of routing of the bulk runoff (englacial or subglacial as defined by Collins, 1979b) and 8^18O to determine the contributions of pre-event and event water to bulk runoff during precipitation events. The pre-event water was defined as a combination of snow meltwater, ice meltwater and groundwater as these flow components could …


Stratigraphy And Structure Of The Southeast Part Of The Portland Basin, Oregon, Kenneth E. Lite Jr. Jan 1992

Stratigraphy And Structure Of The Southeast Part Of The Portland Basin, Oregon, Kenneth E. Lite Jr.

Dissertations and Theses

The southeast part of the Portland Basin has been previously described by other investigators. However, little detailed information existed on the depositional relationships between the units, the various sedimentary fades, or the origin of many of the units.


Glacial Deposits, Vol. 20, 1991-1992, Department Of Geography-Geology Jan 1992

Glacial Deposits, Vol. 20, 1991-1992, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Morphometric Analysis Of Dolines, A. Bondesan, M. Meneghel, U. Sauro Jan 1992

Morphometric Analysis Of Dolines, A. Bondesan, M. Meneghel, U. Sauro

International Journal of Speleology

The doline is the most specific surface form of karst landscapes, which enables one to distinguish them from “normal” erosion landscapes shaped by surface water. From a morphodynamic point of view the doline constitutes an elementary hydrographic unit, comparable to a simple basin, which, with its system of slopes, conveys water to the absorbing points at the bottom into an underground network. The morphometric study of these karst landforms enables a quantitative analysis of karst environment. Comparisons of the various parameters may give unexpected results and lead to new hypotheses about the evolution and the dynamism of the karst “geo-ecosystem”. …


The Sloan Sag: A Mid-Miocene Volcanotectonic Depression, North-Central Mccullough Mountains, Southern Nevada, Hayden L. Bridwell Dec 1991

The Sloan Sag: A Mid-Miocene Volcanotectonic Depression, North-Central Mccullough Mountains, Southern Nevada, Hayden L. Bridwell

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the Hidden Valley area of the north-central McCullough Mountains, southern Nevada, mid-Miocene andesite and dacite domes, flows and pyroclastic units (the Sloan volcanics) partially fill a sag in the underlying Hidden Valley volcanics. The 13.5 km diameter sag formed during and/or after the eruption of the Sloan volcanics. Sagging was accommodated by a combination of movement on the McCullough Wash fault system, and subsidence into evacuated chambers.

Major, trace and rare-earth element geochemistry suggests that the rocks of the Sloan volcanics belong to four groups, each of which were produced by partial melting of chemically distinct sources. With the …


Climate, Physiography, Geology, Hydrology And Land Use In The North Stirlings Area : A Precursory Report, R Lennard, R A. Nulsen, C E. Southwell Oct 1991

Climate, Physiography, Geology, Hydrology And Land Use In The North Stirlings Area : A Precursory Report, R Lennard, R A. Nulsen, C E. Southwell

Resource management technical reports

No abstract provided.