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Articles 26461 - 26490 of 29958

Full-Text Articles in Geology

Description Of The Pelagic Zooplankton And Fish Communities Of Lakes Powell And Mead, United States Geological Survey Jan 1999

Description Of The Pelagic Zooplankton And Fish Communities Of Lakes Powell And Mead, United States Geological Survey

All U.S. Government Documents (Utah Regional Depository)

Fishery biologists from Arizona, Nevada, and Utah have been faced with the imposing dilemma of monitoring the pelagic fishery of Lakes Powell and Mead. Standard sampling procedures typically used to monitor shoreline fisheries are simply inadequate for the deep volumes of pelagic habitat found in these two reservoirs. Nearly a decade ago, Arizona and Nevada biologists recommended that hydroacoustics be used to monitor these communities (Persons and Dreyer 1987a,b, NDOW 1994). However, for various reasons an acoustical monitoring program was never fully implemented. This study represents the first attempt to describe the pelagic fishery of either reservoir using acoustic technology.

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Available Resources Of The Fire Clay Coal In Part Of The Eastern Kentucky Coal Field, Stephen F. Greb, Gerald A. Weisenfluh, Robert E. Andrews, John K. Hiett, James C. Cobb, Richard E. Sergeant Jan 1999

Available Resources Of The Fire Clay Coal In Part Of The Eastern Kentucky Coal Field, Stephen F. Greb, Gerald A. Weisenfluh, Robert E. Andrews, John K. Hiett, James C. Cobb, Richard E. Sergeant

Report of Investigations--KGS

Available resources for the Fire Clay coal were calculated for a 15-quadrangle area in the Eastern Kentucky Coal Field. Original coal resources were estimated to be 1.8 billion tons (BT). Coal mined or lost in mining was estimated at 449 million tons (MT), leaving 1.3 BT of remaining Fire Clay resources in the study area. Of the remaining resources, 400 MT is restricted from mining, primarily because the coal is less than 28 in. thick, normally considered too thin to mine underground using present technology. The total coal available for mining in the study area is 911 MT, or 52 …

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Merrick County Test Hole Logs, Frank A. Smith Jan 1999

Merrick County Test Hole Logs, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Sarpy County Test Hole Logs, Raymond R. Burchett, Frank A. Smith Jan 1999

Sarpy County Test Hole Logs, Raymond R. Burchett, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Classification Of Torbanite And Cannel Coal. I. Insights From Petrographic Analysis Of Density Fractions., Zhiwen Han, Michael A. Kruge, John C. Crelling, David F. Bensley Jan 1999

Classification Of Torbanite And Cannel Coal. I. Insights From Petrographic Analysis Of Density Fractions., Zhiwen Han, Michael A. Kruge, John C. Crelling, David F. Bensley

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Torbanite and cannel coal are considered to be coals because of their low mineral content and overall physical morphology. However, the texture and composition of the organic matter in torbanite and cannel coal are similar to the kerogen occurring in oil shales and lacustrine source rocks. Therefore, understanding the nature and origin of organic components in torbanite and cannel coal is of significance in the study of kerogen and petroleum formation. In this research, a set of torbanites and cannel coals from different locations throughout the world were petrographically characterized and processed using a density gradient centrifugation (DGC) technique. Microscopically, …

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A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry Jan 1999

A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The nature of the contribution of the various types of algae to sedimentary organic matter continues to be a topic of research interest. Crustose red algae have however received less attention than other types. The fossil calcareous red algae (Rhodophyta) analyzed in this study are two relatively unrecrystallized specimens of Parachaetetes (Family Solenoporacea) from the lower part of the Ste. Genevieve Formation (Carboniferous, Visean) in Union County, Illinois, USA. They occurred in the patch reef phase of a small carbonate mudmound-patchreef. The three modern specimens (collected and identified by F. Collier) are the crustose algae Lithothamnion, Clathromorphum and Phymatolithon …

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Chemistry Of Maceral And Groundmass Density Fractions Of Torbanite And Cannel Coal, Zhiwen Han, Michael A. Kruge Jan 1999

Chemistry Of Maceral And Groundmass Density Fractions Of Torbanite And Cannel Coal, Zhiwen Han, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Microscopically, torbanite and cannel coal are composed of coarser macerals set in a fine-grained to amorphous groundmass. It is often assumed that the amorphous groundmass is genetically related to the distinct macerals. The separation of macerals and groundmass from 14 late Paleozoic torbanite, cannel, and humic coals permits the analysis of individual constituents using elemental analysis and flash pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Cluster and principal component analyses of the Py-GC/MS data further reveal the chemical similarities and differences between the various constituents. Pyrolyzates of Botryococcus-related alginites are characterized by an abundance of normal alkadienes, alkenes, and alkanes. Even their …

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Classification Of Torbanite And Cannel Coal. Ii. Insights From Organic Geochemical And Multivariate Statistical Analysis, Zhiwen Han, Michael A. Kruge Jan 1999

Classification Of Torbanite And Cannel Coal. Ii. Insights From Organic Geochemical And Multivariate Statistical Analysis, Zhiwen Han, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Petrographic and megascopic criteria have traditionally been used as the basis for the classification of torbanite and cannel coal. For this study, it was hypothesized that modern analytical organic geochemical and multivariate statistical techniques could provide an alternative approach. Towards this end, the demineralized residues of 14 torbanite (rich in Botryococcus-related alginite) and cannel (essentially, rich in organic groundmass and/or sporinite) coal samples were analyzed by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Cluster analysis performed on the Py-GC/MS data clearly distinguished the torbanite from the cannel coal, demonstrating a consistency between the chemical properties and the petrographic composition. All the torbanite …

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Howard County Test Hole Logs, Vincent H. Dreeszen Jan 1999

Howard County Test Hole Logs, Vincent H. Dreeszen

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Stable Isotope And Crystal Chemistry Of Tourmaline Across Pegmatite - Country Rock Boundaries At Black Mountain And Mount Mica, Southwestern Maine, U.S.A, Darby Dyar, Charles V. Guidott, Daniel P. Core, Katherine M. Wearn, Michael A. Wise, Carl A. Francis, Kathleen Johnson, John B. Brady, J. David Robertson, Laura R. Cross Jan 1999

Stable Isotope And Crystal Chemistry Of Tourmaline Across Pegmatite - Country Rock Boundaries At Black Mountain And Mount Mica, Southwestern Maine, U.S.A, Darby Dyar, Charles V. Guidott, Daniel P. Core, Katherine M. Wearn, Michael A. Wise, Carl A. Francis, Kathleen Johnson, John B. Brady, J. David Robertson, Laura R. Cross

Geosciences: Faculty Publications

Major element and stable isotope chemistry of tourmaline from two complexly-zoned rare element pegmatites has been studied to gain insights into the processes by which the pegmatites were formed. Two locations in the Oxford Pegmatite Field of western Maine, U.S.A., were chosen for this study: Black Mountain, an isolated body located in sillimanite zone, highly sulfidic metapelites and quartzite; and Mount Mica, which is bounded by schists and pegmatite and aplitic granite bodies commonly having gradational contacts with each other. At each locality, tourmaline was sampled from the surrounding country rocks into the contact and wall zones through to the …

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Surveyor: Mobile Highway Inventory And Measurement System, Norbert H. Maerz, Steve Mckenna Jan 1999

Surveyor: Mobile Highway Inventory And Measurement System, Norbert H. Maerz, Steve Mckenna

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Surveyor is a mobile highway data collection system designed to collect measurement data about objects, features, structures, and landmarks located along highways and roadways for highway planning, management, and maintenance. It creates classified inventories annotated with object dimensions, object position relative to the road, and global position reference. The mobile data collection part of the system consists of a high-speed multifunction vehicle with minimum complement of a right-of-way video system with a precisely calibrated high-resolution video camera, a distance-measuring instrument for spatial positioning, a gyroscopic geometries system, and an ultrasonic grade system for precise measurement of vehicle attitude. Data acquisition …

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Kearney County Test Hole Logs, Scott E. Summerside Jan 1999

Kearney County Test Hole Logs, Scott E. Summerside

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Oil And Gas Map Of The Corbin 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall Jan 1999

Oil And Gas Map Of The Corbin 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall

Map and Chart--KGS

No abstract provided.

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Tectonic Implications Of Erosional And Depositional Features In Upper Meramecian And Lower Chesterian (Mississippian) Rocks Of South-Central And East-Central Kentucky, Garland R. Dever Jr. Jan 1999

Tectonic Implications Of Erosional And Depositional Features In Upper Meramecian And Lower Chesterian (Mississippian) Rocks Of South-Central And East-Central Kentucky, Garland R. Dever Jr.

Bulletin--KGS

Erosional and depositional features in upper Meramecian and lower Chesterian (Mississippian) carbonate rocks of south-central and east-central Kentucky suggest the influence of coeval structural activity. The study area, which extends from Pulaski County northeastward into Powell County, is underlain by (1) the Greenwood Anomaly, a large north-trending gravity anomaly, which probably represents part of a Precambrian rift system, and (2) the western part of the Rome Trough, an east-trending graben-like structure, which represents a Late Precambrian to Cambrian continental rift zone. The study focused on the St. Louis Limestone and lower Monteagle Limestone of south-central Kentucky and correlative carbonate rocks …

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Ground-Water Quality In Kentucky: Nitrate-Nitrogen, Philip G. Conrad, Daniel I. Carey, James S. Webb, James S. Dinger, Matthew J. Mccourt Jan 1999

Ground-Water Quality In Kentucky: Nitrate-Nitrogen, Philip G. Conrad, Daniel I. Carey, James S. Webb, James S. Dinger, Matthew J. Mccourt

Information Circular--KGS

No abstract provided.

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2018 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach Jan 1999

2018 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach

Conservation and Survey Division: Faculty and Staff Publications

Nineteen participants completed the 2018 Water Leaders Academy bringing the total number of graduates to 120 since the inception of the program in 2011. Assessment of participants’ transformational leadership skills, champion of innovation skills, water knowledge and engagement, civic capacity, and entrepreneurial leadership behaviors showed a significant increase over the course of the year, from both participants’ and their raters’ perspectives. Feedback from participants was highly positive and constructive. Participant concerns were addressed, and only minor changes are planned for the 2019 Academy curriculum. Results of the program assessment indicate that the curriculum is meeting Academy objectives. Most importantly, Alumni …

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Major- And Minor-Element Analysis Of Apollo 14 Volcanic Green Glasses B, And Petrogenic Modeling Of Apollo 14 Green Glasses A And B, Vera Assis Fernandes Jan 1999

Major- And Minor-Element Analysis Of Apollo 14 Volcanic Green Glasses B, And Petrogenic Modeling Of Apollo 14 Green Glasses A And B, Vera Assis Fernandes

Geology Theses and Dissertations

The lunar picritic volcanic glasses have been identified as being quenched samples of primary magmas extruded onto the lunar surface via fire-fountains. The study of the composition of these glasses is of extreme importance for the understanding of the Moon's mantle composition and petrogenetic processes.
Based on their chemical signature (low-Ti and high Mg#) and physical characteristics, the lunar picritic glasses are believed to represent primary magmas. Experimental data suggest that these melts formed at 360-500 km depth (18-25 kbar) in the lunar mantle, and were transported onto the lunar surface through a "channel" network (McKenzie, 1985b) that isolated these …

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The Geology Of The Liberty-Orrington-Passagassawakeag/Fredericton Trough Terrane Boundary In The Bucksport-Orland Area, Coastal Maine, Heather A. Short Jan 1999

The Geology Of The Liberty-Orrington-Passagassawakeag/Fredericton Trough Terrane Boundary In The Bucksport-Orland Area, Coastal Maine, Heather A. Short

Geology Theses and Dissertations

The Liberty-Orrington fault separates two tectonic terranes of widely different lithologies and metamorphic grades within the Coastal Lithotectonic Belt of Maine. While the juxtaposition of the sillimanite-bearing Passagassawakeag gneiss and the chlorite grade Bucksport Formation (turbidites) requires a fault between them, field evidence for, and an understanding of, the nature of the fault has hitherto been lacking. Although the Liberty-Orrington fault has previously been interpreted as a thrust, strike-slip, and/or normal fault, the most recent debate has been centered around two models of Acadian amalgamation involving thrusting of the Passagassawakeag terrane from the southeast vs. thrusting from beneath central Maine …

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Cambrian And Deeper Tests Of Kentucky, 1999 Includes Proposed Tests (Permitted Locations), Brandon C. Nuttall Jan 1999

Cambrian And Deeper Tests Of Kentucky, 1999 Includes Proposed Tests (Permitted Locations), Brandon C. Nuttall

Map and Chart--KGS

No abstract provided.

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Mass Flux Of Agricultural Nonpoint-Source Pollutants In A Conduit-Flow-Dominated Karst Aquifer, Logan County, Kentucky, James C. Currens Jan 1999

Mass Flux Of Agricultural Nonpoint-Source Pollutants In A Conduit-Flow-Dominated Karst Aquifer, Logan County, Kentucky, James C. Currens

Report of Investigations--KGS

Changes in water quality in a karst ground-water basin used intensively for agriculture are being measured before, during, and after the implementation of best management practices (BMP’s) and other management practices, to determine the success of such programs in protecting ground water. The study was divided into three phases. The results of the first two phases are included in this report and cover research conducted between August 1990 and October 1994. During phase I of the study the overall ground-water quality of the basin and its hydrogeology were investigated. Phase II began monitoring the water quality at Pleasant Grove Spring …

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Ground-Water Quality In Kentucky: Fluoride, Philip G. Conrad, Daniel I. Carey, James S. Webb, James S. Dinger, R. Stephen Fisher, Matthew J. Mccourt Jan 1999

Ground-Water Quality In Kentucky: Fluoride, Philip G. Conrad, Daniel I. Carey, James S. Webb, James S. Dinger, R. Stephen Fisher, Matthew J. Mccourt

Information Circular--KGS

Fluoride (F-) is an ion of the element fluorine, and is a natural component in most water resources. According to Hem (1989), fluoride concentrations in fresh water are generally less than 1 mg/L (milligrams per liter), and the concentration of fluoride in the world's oceans is about 1.3 mg/L. The source of most fluoride in natural fresh-water resources is various rocks and minerals in bedrock and sediments.

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Sustainable Development Of Agriculture In Karst Areas, South China, Linhua Song Jan 1999

Sustainable Development Of Agriculture In Karst Areas, South China, Linhua Song

International Journal of Speleology

The exposed carbonate rocks aged from Sinian to Mid-Triassic Periods cover an area of 500,000 km2 in south-west China. In karst areas with spectacular landscapes characterized by magnificent tower karst and conical karst, rare surface drainage systems and prevalent subsurface drainage systems, the environment is ecologically very fragile. The rapid increase of population, over deforested and cultivated lands, worsted the ecological system, causing a higher frequency of draught, flood and various disasters, backward economic development, low living standard of the people. In order to improve the sustainability of the agriculture the experience shows that the following operations should be …

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Karst And Agriculture In Australia, David Gillieson, Mia Thurgate Jan 1999

Karst And Agriculture In Australia, David Gillieson, Mia Thurgate

International Journal of Speleology

Much of the development and degradation of karst lands in Australia has occurred in the last two centuries since European settlement. Recent prolonged El Niño events add further climatic uncertainty and place real constraints on sustainable agriculture. The lower southeast of South Australia is perhaps the one area in Australia where karst, and particularly karst hydrology, impinge on the daily lives of the community in that pollution and overexploitation of the aquifer are readily apparent to the local population. Effluent from intensive dairy farms, piggeries and cheese factories enters the karst and has caused concern over pollution of water supplies. …

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Agricultural Use And Water Quality At Karstic Cuban Western Plain, Juan Reynerio Fagundo Castillo, Patricia González Hernandez Jan 1999

Agricultural Use And Water Quality At Karstic Cuban Western Plain, Juan Reynerio Fagundo Castillo, Patricia González Hernandez

International Journal of Speleology

In the paper some results of studies on the karstic aquifers of the western plain of Cuba are presented and discussed. The intensive exploitation of these aquifers for agriculture use and drinking water supply induces an increase of marine water intrusion, water salinisation and a progressive increase of chemical corrosion with a greater dissolution of carbonates. During the period of study (1983-1998) a trend in the deterioration of water quality was observed by means of a chronological series of hydrochloride content.

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Impacts Of Agricultural Transformation On The Principal Karstic Regions Of France, Jean Nicod, Jean-Noël Salomon Jan 1999

Impacts Of Agricultural Transformation On The Principal Karstic Regions Of France, Jean Nicod, Jean-Noël Salomon

International Journal of Speleology

The recent extension of intensive agriculture on the karst plateaus has caused different types of impact: soil management, generalised and/or localised pollution. Yet paradoxically rural depopulation can also have negative impacts, which largely depend on the characteristics and the hydrological function of the different karst environments. They are often negative, particularly as far as the water quality is concerned, which is why protection measures are undertaken, either in a defined area for a catchment, or in the framework of regional parks. But this is not always the case, so it is appropriate to analyse the problem of karst pollution as …

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Phelps County Test Hole Logs, S. E. Summerside Jan 1999

Phelps County Test Hole Logs, S. E. Summerside

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Groundwater-Level Changes In Nebraska 1996, Abraham H. Chen, Mohan J. Khisty Jan 1999

Groundwater-Level Changes In Nebraska 1996, Abraham H. Chen, Mohan J. Khisty

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Douglas County Test Hole Logs, Raymond R. Burchett, Frank A. Smith Jan 1999

Douglas County Test Hole Logs, Raymond R. Burchett, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Dawson County Test Hole Logs, Frank A. Smith Jan 1999

Dawson County Test Hole Logs, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Hall County Test Hole Logs, Vincent H. Dreeszen Jan 1999

Hall County Test Hole Logs, Vincent H. Dreeszen

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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