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Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, Sue Olafsen Lackey, Robert F. Diffendal Jr., Raymond R. Burchett, Duane A. Eversoll, Rodney J. Tremblay Sep 1997

Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, Sue Olafsen Lackey, Robert F. Diffendal Jr., Raymond R. Burchett, Duane A. Eversoll, Rodney J. Tremblay

Conservation and Survey Division

Field trip guide, for the Nebraska Well Drillers Association, covering northeastern Nebraska geology from September 1997.


Geology Of The Ponca Creek And Keya Paha River Drainage Basins In Nebraska, Robert F. Diffendal Jr. Sep 1997

Geology Of The Ponca Creek And Keya Paha River Drainage Basins In Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The geology of the study area has been investigated many times over more than a century. Interested readers are directed to the report by Diffendal and Voorhies (1994), which gives a more detailed overview of the results of the investigations and lists most of the more important reports about the area’s geology.

The names of the sedimentary rock strata and unlithified sediments exposed in and underlying all or parts of the study area are shown in Table V.I. These formations range in age from more than 85 million years to sediments being deposited today by winds, water, and downslope movements …


Geology Of Niobrara State Park, Knox County, Nebraska, And Adjacent Areas, With A Brief History Of The Park, Gavins Point Dam, And Lewis And Clark Lake, Charles A. Flowerday, Robert F. Diffendal Jr., R. L. Skelly, F. G. Ethridge, D. A. Eversoll, David K. Watkins, B. E. Bailey Sep 1997

Geology Of Niobrara State Park, Knox County, Nebraska, And Adjacent Areas, With A Brief History Of The Park, Gavins Point Dam, And Lewis And Clark Lake, Charles A. Flowerday, Robert F. Diffendal Jr., R. L. Skelly, F. G. Ethridge, D. A. Eversoll, David K. Watkins, B. E. Bailey

Conservation and Survey Division

Location

Niobrara State Park is located in northwestern Knox County, Nebraska, just west of the town of Niobrara and on the west side of the Niobrara River. The present park was opened in the summer of 1987. Mostly north of Nebraska Highway 12, the site is hilly with bluffs overlooking the Missouri and Niobrara rivers. Excellent facilities include paved roads, cabins, an outdoor swimming pooi, hiking trails, picnic and camping sites, horseback riding trails, playgrounds, restrooms, a group lodge, and an interpretive shelter. Many vantage points in the park have beautiful views of the lower Niobrara Valley and the middle …


Biology Of Shovelnose Sturgeon, Scaphirhynchus Platorynchus, In The Lower Platte River, Nebraska, Robin L. Hofpar Aug 1997

Biology Of Shovelnose Sturgeon, Scaphirhynchus Platorynchus, In The Lower Platte River, Nebraska, Robin L. Hofpar

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

No abstract provided.


Effects Of Ultraviolet Radiation On Attached Diatom Growth And Distribution, Heather Lynn Emsley Hatsell May 1997

Effects Of Ultraviolet Radiation On Attached Diatom Growth And Distribution, Heather Lynn Emsley Hatsell

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

No abstract provided.


Evaluation Of Selected Atmospheric Indices For The Prediction Of Thunderstorms At Omaha, Nebraska, Fred Ladehoff May 1997

Evaluation Of Selected Atmospheric Indices For The Prediction Of Thunderstorms At Omaha, Nebraska, Fred Ladehoff

Open Access Master's Theses (through 2010)

This study examines the values of five stability indices (the Showalter Index, the K Index, the Vertical Totals Index, the Cross Totals Index, and the Total Totals Index) for Omaha, Nebraska during the months of March through September, 1964 through 1973. Index means during thunderstorm periods and non-thunderstorm periods should show a distinct difference. Even though indices can be an important tool, it must be accentuated that indices should never be used as the sole factor in the prediction of thunderstorm or non-thunderstorm occurrences. This study shows that even at the highest skill scores, many mistakes would be made in …


Average Steady Nonuniform Flow In Stratified Formations, Peter Indelman, Vitaly A. Zlotnik May 1997

Average Steady Nonuniform Flow In Stratified Formations, Peter Indelman, Vitaly A. Zlotnik

Department of Earth and Atmospheric Sciences: Faculty Publications

A mathematical model of average nonuniform flow in heterogeneous stratified media is developed. The averaged Darcy's law is obtained by deriving the analytical expression of the effective conductivity tensor for media with small heterogeneities. The fundamental solution of the average flow equation (mean Green function) corresponding to the flow toward a single point source of deterministic discharge is derived. The mean head distribution is calculated for a fully penetrating well, for a finite length well in an infinite domain, and for a dipole well. The concept of equivalent conductivity is defined for use in identifying the formation conductivity properties. The …


Rates, Timing, And Cyclicity Of Holocene Eolian Activity In North-Central United States: Evidence From Varved Lake Sediments, Walter E. Dean Apr 1997

Rates, Timing, And Cyclicity Of Holocene Eolian Activity In North-Central United States: Evidence From Varved Lake Sediments, Walter E. Dean

United States Geological Survey: Staff Publications

Most of the sediment components that accumulated in Elk Lake, northwestern Minnesota, during the Holocene are autochthonous or biogenic, delivered to the sediment-water interface on a seasonal schedule, preserved in distinct annual laminae (varves). The main allochthonous component is detrital clastic material, as measured by bulk-sediment concentrations of aluminum, sodium, potassium, titanium, and quartz, that enters the lake mostly as eolian dust. The eolian clastic influx to Elk Lake was considerably greater during the mid-Holocene (8–4 ka) than it has been for the past 4000 yr, when periods of increased eolian activity correspond to the time of the Little Ice …


Three-Dimensional Upper Crustal Velocity Structure Beneath San Francisco Peninsula, California, Tom Parsons, Mary Lou Zoback Jan 1997

Three-Dimensional Upper Crustal Velocity Structure Beneath San Francisco Peninsula, California, Tom Parsons, Mary Lou Zoback

United States Geological Survey: Staff Publications

This paper presents new seismic data from, and crustal models of the San Francisco Peninsula. In much of central California the San Andreas fault juxtaposes the Cretaceous granitic Salinian terrane on its west and the Late Mesozoic/Early Tertiary Franciscan Complex on its east. On San Francisco Peninsula, however, the present-day San Andreas fault is completely within a Franciscan terrane, and the Pilarcitos fault, located southwest of the San Andreas, marks the Salinian-Franciscan boundary. This circumstance has evoked two different explanations: either the Pilarcitos is a thrust fault that has pushed Franciscan rocks over Salinian rocks or the Pilarcitos is a …


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. …


Herbicides And Their Metabolites In Rainfall: Origin, Transport, And Deposition Patterns Across The Midwestern And Northeastern United States, 1990-1991, Donald Goolsby, E. Michael Thurman, Michael Pomes, Michael Meyer, William Battaglin Jan 1997

Herbicides And Their Metabolites In Rainfall: Origin, Transport, And Deposition Patterns Across The Midwestern And Northeastern United States, 1990-1991, Donald Goolsby, E. Michael Thurman, Michael Pomes, Michael Meyer, William Battaglin

United States Geological Survey: Staff Publications

Herbicides were detected in rainfall throughout the midwestern and northeastern United States during late spring and summer of 1990 and 1991. Herbicide concentrations exhibited distinct geographic and seasonal patterns. The highest concentrations occurred in midwestern cornbelt states following herbicide application to cropland. Volume-weighted concentrations of 0.2-0.4 μg/L for atrazine and alachlor were typical in this area during mid-April through mid-July, and weighted concentrations as large as 0.6- 0.9 μg/L occurred at several sites. Concentrations of 1-3 μg/L were measured in a few individual samples. Atrazine was detected most often followed by alachlor, deethylatrazine, metolachlor, cyanazine, and deisopropylatrazine. The high ratio …


Resource News-Winter 1996-97 Jan 1997

Resource News-Winter 1996-97

Conservation and Survey Division

No abstract provided.


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

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

No abstract provided.


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

No abstract provided.


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 …


Analysis Of Environmental Data With Censored Observations, Shiping Liu, Jye-Chyi Lu, Dana Kolpin, William Meeker Jan 1997

Analysis Of Environmental Data With Censored Observations, Shiping Liu, Jye-Chyi Lu, Dana Kolpin, William Meeker

United States Geological Survey: Staff Publications

The potential threats to humans and to terrestrial and aquatic ecosystems from environmental contamination could depend on the sum of the concentrations of different chemicals. However, direct summation of environmental data is not generally feasible because it is common for some chemical concentrations to be recorded as being below the analytical reporting limit. This creates special problems in the analysis of the data. A new model selection procedure, named forward censored regression, is introduced for selecting an appropriate model for environmental data with censored observations. The procedure is demonstrated using concentrations of atrazine (2-chloro- 4-ethylamino-6-isopropylamino-s-triazine), deethylatrazine (DEA, 2-amino-4-chloro-6-isopropylamino-s-triazine), and deisopropylatrazine …


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 …


Fracture Permeability And Its Relationship To In-Situ Stress In The Dixie Valley, Nevada, Geothermal Reservoir, Colleen A. Barton, Stephen Hickman, Roger H. Morin, Mark D. Zoback, Thomas Finkbeiner, John Sass, Dick Benoit Jan 1997

Fracture Permeability And Its Relationship To In-Situ Stress In The Dixie Valley, Nevada, Geothermal Reservoir, Colleen A. Barton, Stephen Hickman, Roger H. Morin, Mark D. Zoback, Thomas Finkbeiner, John Sass, Dick Benoit

United States Geological Survey: Staff Publications

An extensive suite of spinner flowmeter, high-resolution temperature and borehole televiewer logs were acquired in a 2.7-km-deep well drilled into a fault-hosted geothermal reservoir at Dixie Valley, Nevada. Localized perturbations to wellbore temperature and flow were used to identify hydraulically conductive fractures. Comparison of these data with fracture orientations from the borehole televiewer logs indicates that hydraulically conductive fractures in crystalline rocks within and adjacent to the producing fault zone have an orientation distinct from the overall fracture population. In conjunction with in-situ stress measurements from this well, Coulomb analysis indicates that these permeable fractures are critically stressed, potentially active …


Correlation Of Late-Pleistocene Lake-Level Oscillations In Mono Lake, California, With North Atlantic Climate Events, Larry Benson, Steve P. Lund, James W. Burdett, Michaele Kashgarian, Timothy P. Rose, Joseph P. Smoot, Martha Schwartz Jan 1997

Correlation Of Late-Pleistocene Lake-Level Oscillations In Mono Lake, California, With North Atlantic Climate Events, Larry Benson, Steve P. Lund, James W. Burdett, Michaele Kashgarian, Timothy P. Rose, Joseph P. Smoot, Martha Schwartz

United States Geological Survey: Staff Publications

Oxygen-18 (18O) values of sediment from the Wilson Creek Formation, Mono Basin, California, indicate three scales of temporal variation (Dansgaard-Oeschger, Heinrich, and Milankovitch) in the hydrologic balance of Mono Lake between 35,400 and 12,900 14C yr B.P. During this interval, Mono Lake experienced four lowstands each lasting from 1000 to 2000 yr. The youngest low stand, which occurred between 15,500 and 14,000 14C yr B.P., was nearly synchronous with a desiccation of Owens Lake, California. Paleomagnetic secular variation (PSV) data indicate that three of four persistent low stands occurred at the same times as Heinrich events …


First Record Of Common Moorhen Nesting In South Dakota, William A. Meeks, Kenneth F. Higgins Jan 1997

First Record Of Common Moorhen Nesting In South Dakota, William A. Meeks, Kenneth F. Higgins

United States Geological Survey: Staff Publications

The common moorhen (Gallinula chloropus) is widespread in North America, but is not very abundant throughout its range (Greij 1994, Common Moorhen, Pages 145-157 in Tacha and Braun [eds.] Migratory Shore and Upland Game Bird Management in North America, Allen Press, Lawrence). In North Dakota its status is accidental (Konrad 1983, Prairie Nat. 15:144); in South Dakota it is considered a casual visitor and a probable breeding species (South Dakota Ornithologists' Union 1991, The Birds of South Dakota, Northern State University Press, Aberdeen; Peterson 1995, The Breeding Bird Atlas of South Dakota, Northern State University Press, Aberdeen).


Nearly Synchronous Climate Change In Thenorthern Hemisphere During The Last Glacial Termination, Larry Benson, James Burdett, Steve Lund, Michaele Kashgarian, Scott Mensing Jan 1997

Nearly Synchronous Climate Change In Thenorthern Hemisphere During The Last Glacial Termination, Larry Benson, James Burdett, Steve Lund, Michaele Kashgarian, Scott Mensing

United States Geological Survey: Staff Publications

The climate of the North Atlantic region underwent a series of abrupt cold/warm oscillations when the ice sheets of the Northern Hemisphere retreated during the last glacial termination (17.7– 11.5 kyr ago). Evidence for these oscillations, which are recorded in European terrestrial sediments as the Oldest Dryas/Bølling/ Older Dryas/Allerød/Younger Dryas vegetational sequence1,2, has been found in Greenland ice cores3,4. The geographical extent of many of these oscillations is not well known5,6, but the last major cold event (the Younger Dryas) seems to have been global in extent7–10. Here we present evidence of …


Fractured-Aquifer Hydrogeology From Geophysical Logs; The Passaic Formation, New Jersey, Roger H. Morin, Glen B. Carleton, Stephane Poirier Jan 1997

Fractured-Aquifer Hydrogeology From Geophysical Logs; The Passaic Formation, New Jersey, Roger H. Morin, Glen B. Carleton, Stephane Poirier

United States Geological Survey: Staff Publications

The Passaic Formation consists of gradational sequences of mudstone, siltstone, and sandstone, and is a principal aquifer in central New Jersey. Ground-water flow is primarily controlled by fractures interspersed throughout these sedimentary rocks and characterizing these fractures in terms of type, orientation, spatial distribution, frequency, and transmissivity is fundamental towards understanding local fluid-transport processes. To obtain this information, a comprehensive suite of geophysical logs was collected in 10 wells roughly 46 m in depth and located within a .05 km2 area in Hopewell Township, New Jersey. A seemingly complex, heterogeneous network of fractures identified with an acoustic televiewer was …


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 …


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.


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 …


Sem Analysis Of Quartz Sand Grain Surface Textures Indicates Alluvial/Colluvial Origin Of The Quaternary "Glacial" Boulder Clays At Huangshan (Yellow Mountain), East-Central China, P. E. Helland, Pei-Hua Huang, Robert F. Diffendal Jr. Jan 1997

Sem Analysis Of Quartz Sand Grain Surface Textures Indicates Alluvial/Colluvial Origin Of The Quaternary "Glacial" Boulder Clays At Huangshan (Yellow Mountain), East-Central China, P. E. Helland, Pei-Hua Huang, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Geomorphic features and Pleistocene deposits on Huangshan have been attributed to glaciation. Recent reassessment questions this interpretation. As part of the reassessment, quartz sand grains from deposits identified as glacial boulder clays (till composed of boulders in a clay or silt matrix) were analyzed by scanning electron microscope for evidence of their sedimentary history. Surface textures found on the boulder-clay grains were compared with those on grains with known sedimentary histories including glacial, grus, colluvial, and alluvial grains. The analysis shows that the grains lack typical glacial textures. The surface textures present indicate a complex history. Non-uniformly weathered grain surfaces …


Geology And Ground Water, Cheyenne County, Nebraska, Robert F. Diffendal Jr. Jan 1997

Geology And Ground Water, Cheyenne County, Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The oldest rock unit exposed in Cheyenne County is the upper part of the Brule Formation, which is the youngest formation of the White River Group of the Oligocene epoch (33-29 million years old). Surface outcrops, road cuts, and railroad cuts through the Brule Formation occur along the sides of valleys along Lodgepole Creek from just east of Sidney westward to the vicinity of Brownson, along the valley sides of Sidney Draw and its tributaries, and along the sides of an unnamed drainageway northwest of Colton. Test drilling and drilling for wells along the floor of Lodgepole Creek have revealed …


Ground Water, Robert F. Diffendal Jr. Jan 1997

Ground Water, Robert F. Diffendal Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

A geologic overview of the groundwater supply underlying Cheyenne County, Nebraska (1997).


Geology, Robert F. Diffendal Jr. Jan 1997

Geology, Robert F. Diffendal Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

An overview of the geology of Cheyenne County, Nebraska.