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A Land-Use And Water-Quality History Of White Rock Lake Reservoir, Dallas, Texas, Based On Paleolimnological Analyses, J. Platt Bradbury, Peter C. Van Metre Jan 1997

A Land-Use And Water-Quality History Of White Rock Lake Reservoir, Dallas, Texas, Based On Paleolimnological Analyses, J. Platt Bradbury, Peter C. Van Metre

United States Geological Survey: Staff Publications

White Rock Lake reservoir in Dallas, Texas contains a 150-cm sediment record of silty clay that documents land-use changes since its construction in 1912. Pollen analysis corroborates historical evidence that between 1912 and 1950 the watershed was primarily agricultural. Land disturbance by plowing coupled with strong and variable spring precipitation caused large amounts of sediment to enter the lake during this period. Diatoms were not preserved at this time probably because of low productivity compared to diatom dissolution by warm, alkaline water prior to burial in the sediments. After 1956, the watershed became progressively urbanized. Erosion decreased, land stabilized, and …


Two-Dimensional Seismic Image Of The San Andreas Fault In The Northern Gabilan Range, Central California Evidence For Fluids In The Fault Zone, C. Thurber, S. Roecker, W. Ellsworth, Y. Chen, W. Lutter, R. Sessions Jan 1997

Two-Dimensional Seismic Image Of The San Andreas Fault In The Northern Gabilan Range, Central California Evidence For Fluids In The Fault Zone, C. Thurber, S. Roecker, W. Ellsworth, Y. Chen, W. Lutter, R. Sessions

United States Geological Survey: Staff Publications

A joint inversion for two-dimensional P-wave velocity (Vp), P-to-S velocity ratio (Vp/Vs), and earthquake locations along the San Andreas fault (SAF) in central California reveals a complex relationship among seismicity, fault zone structure, and the surface fault trace. A zone of low Vp andh ighV p/Vs lies beneatht he SAF surfacetr ace( SAFST), extending to a depth of about 6 km. Most of the seismic
activity along the SAF occurs at depths of 3 to 7 km in a southwest-dippingz one that roughly intersectst he SAFST, and lies near the southweset dgeo f the low Vp and high Vp/Vs zones. …


Geologic Map Of The Scottsbluff, 1 ° X 2 ° Quadrangle, Nebraska And Colorado, James B. Swinehart, Robert F. Diffendal Jr. Jan 1997

Geologic Map Of The Scottsbluff, 1 ° X 2 ° Quadrangle, Nebraska And Colorado, James B. Swinehart, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

This map is necessarily generalized. For more detailed information, consult the geologic data stored in files of the Conservation and Survey Division, University of Nebraska-Lincoln. Other geologic maps at different scales that include all or parts of the map area are by Darton (1903a,b,c), Lugn (1939), Weeks and Gutentag (1981), and Weeks and otners (1988). Detailed groundwater investigations of parts of the map area were done by Wenzel and others (1946). Babcock and Visher (1951, 1952), Bjorklund (1957), Bjorklund and Brown (1957), Smith (1966, 1969), Smith and Souders (1971,1975). Souders (1986), Gottula (1993), and Verstraeten and others (1995).

Introduction

The …


Effect Of Sulfate On The Release Rate Of Al3+ From Gibbsite In Low-Temperature Acidic Waters, Moira K. Ridley, David J. Wesolowski, Donald A. Palmer, Pascale Bénézeth, Richard Kettler Jan 1997

Effect Of Sulfate On The Release Rate Of Al3+ From Gibbsite In Low-Temperature Acidic Waters, Moira K. Ridley, David J. Wesolowski, Donald A. Palmer, Pascale Bénézeth, Richard Kettler

Department of Earth and Atmospheric Sciences: Faculty Publications

Solubility experiments were performed at 5 °C by reacting 1 g of powdered gibbsite with 45 g of aqueous H2SO4-NaCl and HCl-NaCl (0.01 m H+) solutions at 0.1 m ionic strength. The kinetics of dissolution were monitored under extremely undersaturated conditions and appeared to favor a zero-order rate-determining process. The dissolution rate of gibbsite in the sulfate solution was approximately 10 times faster than in the HCl solution, which is consistent with trends reported in the literature for studies performed at higher temperatures. The enhanced dissolution kinetics of gibbsite (and by analogy, other aluminum-containing minerals) in …


Application Of Environmental Organic Petrology And Geochemistry To Fingerprint Organic Pollutants In The Recent Sediments Of Lake Ontario, Prasanta K. Mukhopadhyay, Michael A. Kruge, C.F. Michael Lewis Jan 1997

Application Of Environmental Organic Petrology And Geochemistry To Fingerprint Organic Pollutants In The Recent Sediments Of Lake Ontario, Prasanta K. Mukhopadhyay, Michael A. Kruge, C.F. Michael Lewis

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Selected surface sediment samples (sediment depth 0-10 cm) collected in the Niagara basin (western Lake Ontario) were chosen for organic matter characterization using organic petrological and geochemical techniques normally reserved for the study of coal, petroleum source rock and crude oil. The study was performed to assess the effectiveness of these techniques in discriminating between natural and anthropogenic organic matter and to determine the extent of organic pollution of the lake sediments. The organic carbon contents of the samples vary from 1.5 to 3.5%, with upper layer (0-5 cm) samples have higher TOC values than those from the lower layer …


Comparison Of Source Rock Geochemistry Of Selected Rocks From The Schei Point Group And Ringnes Formation, Sverdrup Basin, Arctic Canada, P. K. Mukhopadhyay, F. Goodarzi, Michael A. Kruge, M. H. Alimi Jan 1997

Comparison Of Source Rock Geochemistry Of Selected Rocks From The Schei Point Group And Ringnes Formation, Sverdrup Basin, Arctic Canada, P. K. Mukhopadhyay, F. Goodarzi, Michael A. Kruge, M. H. Alimi

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Organic-rich from the Schei Point group (middle to late Triassic in age) and the Ringnes formation (late Jurassic) from the Sverdrup basin of the Canadian arctic archipelago have been geochemically evaluated for source rock characterization. Most samples from the Schei Point group are organic-rich (> 2% TOC) and are considered as immature to mature oil-prone source rocks [kerogen types I, I-II (IIA) and II (IIA)]. These kerogen types contain abundant AOM1, AOM2 and alginite (Tasmanales, Nostocopsis, Leiosphaeridia, acritarch and dinoflagellate) with variable amounts of vitrinite, inertinite and exinite. Samples from the Ringnes formation contain dominant vitrinite and inertinite …


How Accurate Are Uk's Nitrogen Recommendations For Corn?, Kenneth L. Wells, James E. Dollarhide, David C. Ditsch Jan 1997

How Accurate Are Uk's Nitrogen Recommendations For Corn?, Kenneth L. Wells, James E. Dollarhide, David C. Ditsch

Soil Science News and Views

Average corn yields produced on soils with high yield potential have steadily been increasing in Kentucky during the past several years. Yields from such soils in years with adequate amounts of rainfall well distributed over the growing season (May-September) may average 180 to 200 bushels per acre. A bushel of corn with crude protein content of 8 to 9% contains about 1.3 to 1.4% total nitrogen (N) on a dry matter basis. This is about 0.6 to 0.7 lbs total N per bushel of corn (at 15.5% moisture), or 108 to 126 lbs N per acre for a 180 bu/A …


Economics Of Precision Farming: Payoff In The Future, Jess Lowenberg-Beboer Jan 1997

Economics Of Precision Farming: Payoff In The Future, Jess Lowenberg-Beboer

Soil Science News and Views

Precision agriculture is an infant technology. This infant has some of the signs of eventual greatness, but its full capacities will not be evident for some years. Like all infants, it will require an investment of time and resources to help it to maturity. This investment will have some short term payoff, but the main benefits will be in the future.

The purpose of this presentation is to help you manage your adoption of precision farming technology for that future payoff. The specific objectives will be to:review what we have learned about the economics of precision farming, identify future benefits, …


Composite Section Of Cretaceous Rocks In Nebraska, R. R. Burchett Jan 1997

Composite Section Of Cretaceous Rocks In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


The Effects Of Sparging On P- And Sh- Vertical Seismic Profiles, P. Michaels, W. Barrash Jan 1997

The Effects Of Sparging On P- And Sh- Vertical Seismic Profiles, P. Michaels, W. Barrash

CGISS Publications and Presentations

While the introduction of pressurized air into an unconsolidated, coarse-grained fluvial aquifer might well be expected to affect the P-wave velocity profile below the water table, we have found that S-waves are also sensitive to changes induced by air sparging. In a study spanning over a year of sparging, observations of both P- and S-waves were conducted by Vertical Seismic Profiling (VSP). While the primary objective was to characterize the aquifer, we have found that air sparging has significantly affected both P- and S-wave propagation. Below the water table we have observed as much as a 54% decrease in P-wave …


Natural Responses Of Shallow Lakes And Wetlands For Measuring And Analyzing Impacts Of Climatic/Environmental Change, D. C. Rundquist, D. C. Gosselin Jan 1997

Natural Responses Of Shallow Lakes And Wetlands For Measuring And Analyzing Impacts Of Climatic/Environmental Change, D. C. Rundquist, D. C. Gosselin

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


The Effects Of Plains Pocket Gophers On Two Varieties Of Alfalfa, Debra S. Baker Jan 1997

The Effects Of Plains Pocket Gophers On Two Varieties Of Alfalfa, Debra S. Baker

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Characteristics Of Street Sweepings In Florida, Robert Brinkmann, Jeffrey G. Ryan, Mark Billus Jan 1997

Characteristics Of Street Sweepings In Florida, Robert Brinkmann, Jeffrey G. Ryan, Mark Billus

Geology Faculty Publications

No abstract provided.


Separation And Artificial Maturation Of Macerals From Type Ii Kerogen, Michael A. Kruge, Patrick Landais, David F. Bensley, B Artur Stankiewicz, Marcel Elie, Olivier Ruau Jan 1997

Separation And Artificial Maturation Of Macerals From Type Ii Kerogen, Michael A. Kruge, Patrick Landais, David F. Bensley, B Artur Stankiewicz, Marcel Elie, Olivier Ruau

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Immature Type II kerogen (HI= 660 mg/g) from the Lower Toarcian of the Paris Basin was separated into an alginite concentrate (HI = 952 mg/g) and an amorphous organic matter (AOM) concentrate (HI = 573 mg/g) by density centrifugation. The flash pyrolyzate of the alginite is characterized by high relative concentrations of several series of n-alkanones and n-alkenones (including mid-chain alkyl ketones), in addition to n-alkanes, n-alk-1-enes and n-alkadienes. To our knowledge, this Toarcian alginite is the oldest example of marine organic matter whose pyrolyzate contains mid-chain alkanones in such high relative concentrations. In sharp …


A Deep-To-Shallow Transition In The Fort Payne Formation (Lower Mississippian), Kentucky Highway 61, Cumberland County, Kentucky, David L. Meyer, Paul E. Potter, Jennifer L. Thies, William I. Ausich, Stephen A. Leslie Jan 1997

A Deep-To-Shallow Transition In The Fort Payne Formation (Lower Mississippian), Kentucky Highway 61, Cumberland County, Kentucky, David L. Meyer, Paul E. Potter, Jennifer L. Thies, William I. Ausich, Stephen A. Leslie

Map and Chart--KGS

The Fort Payne Formation of the Cumberland Saddle region of south-central Kentucky and north-central Tennessee is part of a vast marine sedimentation system that extended over much of North America during the Early Mississippian Period; broadly similar facies reached from Georgia through Tennessee and Kentucky, into western Illinois and Missouri, and into New Mexico and the northern Rockies (Pryor and Sable, 1974). Throughout North America the Fort Payne and its equivalents overlie a black shale (in Kentucky called the Chattanooga Shale) and underlie thick carbonates (in Kentucky, the Warsaw Formation and younger middle Mississippian limestones).

Six miles south of Burkesville, …


Oil And Gas Map Of The Middlesboro 30 X 60 Minute Quadrangle, Kentucky, Anna E. Watson, Lance G. Morris, Brandon C. Nuttall, Daniel I. Carey Jan 1997

Oil And Gas Map Of The Middlesboro 30 X 60 Minute Quadrangle, Kentucky, Anna E. Watson, Lance G. Morris, Brandon C. Nuttall, Daniel I. Carey

Map and Chart--KGS

The purpose of the oil and gas map series is to portray the distribution of oil and gas resources in a manner useful to the oil and gas industry and to others interested in subsurface research.


Pelletized Lime - How Quickly Does It React, Lloyd W. Murdock Jan 1997

Pelletized Lime - How Quickly Does It React, Lloyd W. Murdock

Soil Science News and Views

Pelletized lime is made by granulating finely ground agricultural (ag) lime. It may be dolomitic or calcitic depending on the nature of the original limestone. The fine lime particles are bonded together with lignosulfonates during the pelletizing process. In general, the pelletized lime contains about 9% lignosulfonates. Pelletized limestone is a product that has been on the market for many years. The price of the material on a per ton basis is considerably higher than bulk ag lime, so its use has mainly been confined to specialty markets, with little use in production agriculture. However, the product is becoming more …


Tillage Slows Fecal Bacteria Infiltration Through Soil, Mark S. Coyne, S. W. Mcmurry, E. Perfect Jan 1997

Tillage Slows Fecal Bacteria Infiltration Through Soil, Mark S. Coyne, S. W. Mcmurry, E. Perfect

Soil Science News and Views

Bacterial pathogens can degrade ground water quality by infiltrating and eroding from land treated with poultry wastes. The potential for ground water contamination (as well as associated health risks and cost of water treatment) greatly depends on the depth of soil to the water table or bedrock and soil structure. Pathogens must move through the soil profile to contaminate ground water (although sinkholes can provide a direct channel from the soil surface to the water table in karst areas). Deep soils have less potential for contamination than shallow soils. Structureless soils retain fecal bacteria better than well structured soils. Research …


Soil Management For Intensive Grazing, Kenneth L. Wells, Charles T. Dougherty Jan 1997

Soil Management For Intensive Grazing, Kenneth L. Wells, Charles T. Dougherty

Soil Science News and Views

Recycling of plant nutrients is of major concern in managing paddocks in pasturefields for intensive grazing. Redistribution of nutrients present in fecal and urine deposits is an important issue in growing climatically and seasonally-adapted forage species and for efficient conversion of herbage into animal products while adding to the sustainability of the system. Some of the questions that arise in managing soils for intensive grazing are discussed below.


Hydrogeology And Ground-Water Monitoring Of Coal-Ash Disposal Sites In A Karst Terrane Near Burnside, South-Central Kentucky, Shelley Minns Hutcheson, Lyle V. A. Sendlein, James S. Dinger, James C. Currens, Arsin M. Sahba Jan 1997

Hydrogeology And Ground-Water Monitoring Of Coal-Ash Disposal Sites In A Karst Terrane Near Burnside, South-Central Kentucky, Shelley Minns Hutcheson, Lyle V. A. Sendlein, James S. Dinger, James C. Currens, Arsin M. Sahba

Report of Investigations--KGS

The effects of two coal-ash disposal facilities on ground-water quality at the John Sherman Cooper Power Plant, located in a karst region of south-central Kentucky, were evaluated using dye traces in springs. Springs were used for monitoring rather than wells, because in a karst terrane wells are unlikely to intercept individual conduits.

A closed-out ash pond located over a conduit-flow system discharges to three springs in the upper Salem and Warsaw Formations along Lake Cumberland. Water discharging from these downgradient springs is similar to springs unaffected by ash-disposal facilities and is a calcium-bicarbonate type. No constituent concentrations found in this …


Fresh-Water Aquifer In The Knox Group (Cambrian–Ordovician) Of Central Kentucky, James A. Kipp Jan 1997

Fresh-Water Aquifer In The Knox Group (Cambrian–Ordovician) Of Central Kentucky, James A. Kipp

Report of Investigations--KGS

Fresh water can be found in Cambrian and Ordovician carbonate rocks of the Knox Group in central Kentucky. The top of the aquifer is as much as 300 ft above mean sea level (m.s.l.) on the crest of the Cincinnati Arch, but descends off the flanks of the arch. Water is normally found in the upper 100 to 250 ft of the Knox, primarily in secondary porosity apparently associated with the unconformity at the top of the unit. Knox wells commonly exceed 750 ft in total depth, but because the aquifer is artesian, water rises to an elevation of about …


Composite Section Of Cretaceous Rocks In Nebraska, R.R. Burchett Jan 1997

Composite Section Of Cretaceous Rocks In Nebraska, R.R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


So You Need A Water Well? A Consumer's Guide To Homeowners' Drinking Water, Charles A. Flowerday, Vincent H. Dreeszen Jan 1997

So You Need A Water Well? A Consumer's Guide To Homeowners' Drinking Water, Charles A. Flowerday, Vincent H. Dreeszen

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Chemistry And Environmental Implications Of Thio-Red And 2,4,6-Trimercaptotriazine Compounds, Kevin R. Henke Jan 1997

Chemistry And Environmental Implications Of Thio-Red And 2,4,6-Trimercaptotriazine Compounds, Kevin R. Henke

Theses and Dissertations

Many compounds, including Thio-Red® and 2,4,6-trimercaptotriazine, trisodium salt (TMT-55), have been marketed to precipitate mercury and other heavy metals from water, including contaminated ground waters. For the products to be effective, information is needed on the chemistry of the products, how they precipitate metals from aqueous solutions, and the chemistries and stabilities of the precipitates.

CS32-, HS-, and S2- are the dominant sulfur species in Thio-Red®. They precipitate heavy metals from water as sulfides (e.g., HgS, PbS, and ZnS). Thio-Red® also contains traces of poisonous carbon disulfide (CS2). Additional CS2 could form from reactions between dissolved heavy metals and CS32-. …


Runoff Quality Responses To Cattle-Gazing Strategy And Grassed Buffer Zone Length, Dwayne R. Edwards, Brian T. Larsen, Teng T. Lim Jan 1997

Runoff Quality Responses To Cattle-Gazing Strategy And Grassed Buffer Zone Length, Dwayne R. Edwards, Brian T. Larsen, Teng T. Lim

KWRRI Research Reports

Grazed pastures represent a source of potential nonpoint pollution. In comparison to other nonpoint sources (e.g., row-cropped lands), relatively little information exists regarding possible magnitudes of pollution from grazed pasture; how that pollution is affected by weather, soil, management and other variables; and how the pollution can be minimized. The objective of this study was to assess how the quality of runoff from simulated grazed pasture is influenced by grazing duration (4-12 weeks), grazing strategy (no grazing, conventional grazing and rotational grazing), and by the use of grassed buffer strips (ranging in length from O to 18.3 m) installed down-slope …


Analysis Of Glasses Present In Quartz And Apatite Phenocrysts From Ordovician K-Bentonites In The Mohawk Valley, Ny, Stefanie Dannenmann Jan 1997

Analysis Of Glasses Present In Quartz And Apatite Phenocrysts From Ordovician K-Bentonites In The Mohawk Valley, Ny, Stefanie Dannenmann

Geology Theses and Dissertations

More than 20 bentonites occur in the Middle Ordovician black shales of the Utica Formation that outcrop along tributaries to the Mohawk River in New York State. Pristine melt inclusions within quartz and apatite phenocrysts are commonly found in at least 40% of the bentonites. Constraints on magmatic processes can be obtained by examining the major-, minor- and trace-element variations among different melt inclusions in quartz and apatite phenocrysts from individual bentonites. The melt inclusions in apatite range in composition from rhyodacitic to rhyolitic, while those in quartz are high-silica rhyolites. Most bentonites within the Middle Ordovician sequence in New …


Pre-Thrust Normal Faults And Post-Tectonic Micas In The Taconic Range Of West-Central Vermont, Nicholas W. Hayman Jan 1997

Pre-Thrust Normal Faults And Post-Tectonic Micas In The Taconic Range Of West-Central Vermont, Nicholas W. Hayman

Geology Theses and Dissertations

New geologic maps show that the Champlain Thrust System traces continuously between Shoreham and Benson, Vermont. The Champlain Thrust System consists of at least three internally imbricated thrust slices in continental shelf facies quartzites and carbonates. From north to south there is a structurally controlled thinning of the Champlain Thrust System, and a climbing in stratigraphic level by the thrusts. Within the Champlain Thrust System are a set of across-strike structures which create offsets in the thrusts and the surrounding lithic map unit boundaries. These structures function as lateral ramps in the thrust system geometry and bound thrust duplexes. Often …


Vegetative Filter Strip Removal Of Metals In Runoff From Poultry Litter-Amended Fescuegrass Plots, Dwayne R. Edwards, P. A. Moore Jr., Tommy C. Daniel, Puneet Srivastava, D. J. Nichols Jan 1997

Vegetative Filter Strip Removal Of Metals In Runoff From Poultry Litter-Amended Fescuegrass Plots, Dwayne R. Edwards, P. A. Moore Jr., Tommy C. Daniel, Puneet Srivastava, D. J. Nichols

Biosystems and Agricultural Engineering Faculty Publications

Runoff from land areas amended with poultry (Gallus gallus domesticus) manure can contain elevated concentrations of metals such as Cu, Fe, and Zn. Vegetative filter strips (VFS) can reduce runoff concentrations of animal manure components, but reported studies have typically focused on nutrients and solids rather than metals. This experiment assessed the impact of VFS length (0 to 12 m) on concentrations and mass losses of Cu, Fe, K, Na, Ni, and Zn in runoff from fescuegrass (Festuca arundinacea Schreb.) plots (1.5 m wide × 6 and 12 m long) treated with poultry litter. The runoff was produced from simulated …


Hands-On Geology For Navajo Nation Teachers, Russell Frank Dubiel, Stephen Tom Hasiotis, Steven Christian Semken Jan 1997

Hands-On Geology For Navajo Nation Teachers, Russell Frank Dubiel, Stephen Tom Hasiotis, Steven Christian Semken

United States Geological Survey: Staff Publications

The Navajo Nation comprises the largest land area and the largest population of any Native American community in the United States, and it hosts some of earth's most spectacular geology.


Statistical Modeling Of Agricultural Chemical Occurrence In Midwestern Rivers, William A. Battaglin, Donald A. Goolsby Jan 1997

Statistical Modeling Of Agricultural Chemical Occurrence In Midwestern Rivers, William A. Battaglin, Donald A. Goolsby

United States Geological Survey: Staff Publications

Agricultural chemicals in surface water may constitute a human health risk or have adverse effects on aquatic life. Recent research on unregulated rivers in the midwestern USA documents that elevated concentrations of herbicides occur for 1–4 months following application in late spring and early summer. In contrast, nitrate concentrations in unregulated rivers are elevated during fall, winter, and spring months. Natural and anthropogenic variables of river drainage basins, such as soil permeability, amount of agricultural chemicals applied, or percentage of land planted in corn, affect agricultural chemical concentration and mass transport in rivers.

Presented is an analysis of selected data …