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Full-Text Articles in Earth Sciences

The Pacific Island Mapping Program Of The Us Geological Survey, Frank C. Whitmore Jr. Jan 2001

The Pacific Island Mapping Program Of The Us Geological Survey, Frank C. Whitmore Jr.

United States Geological Survey: Staff Publications

A little-known aspect of the U.S. Geological Survey history is its involvement in preparing terrain intelligence reports during World War II. The Survey's Military Geology Unit was in charge of compiling these reports on areas of possible military operations. Maps were the main part of' these studies; they were compiled from existing maps, geologic and soils literature, aerial and ground photographs, and travelers' accounts. Compiled geologic anti soils maps served as basic data for interpretative maps on such subjects as construction materials. water supply, road and airfield siting and construction, and cross-country movement by tanks.


Evidence For Millennial-Scale Climate Change During Marine Isotope Stages 2 And 3 At Little Lake, Western Oregon, U.S.A., Laurie D. Grigg, Cathy Whitlock, Walter E. Dean Jan 2001

Evidence For Millennial-Scale Climate Change During Marine Isotope Stages 2 And 3 At Little Lake, Western Oregon, U.S.A., Laurie D. Grigg, Cathy Whitlock, Walter E. Dean

United States Geological Survey: Staff Publications

Pollen and geochemical data from Little Lake, western Oregon, suggest several patterns of millennial-scale environmental change during marine isotope stage (MIS) 2 (14,100–27,600 cal yr B.P.) and the latter part of MIS 3 (27,600–42,500 cal yr B.P.). During MIS 3, a series of transitions between warm- and cold-adapted taxa indicate that temperatures oscillated by ca. 2±–4±C every 1000–3000 yr. Highs and lows in summer insolation during MIS 3 are generally associated with the warmest and coldest intervals. Warm periods at Little Lake correlate with warm sea-surface temperatures in the Santa Barbara Basin. Changes in the strength of the subtropical high …


Occurrence Of Cyanazine Compounds In Groundwater: Degradates More Prevalent Than The Parent Compound, Dana Kolpin, E. Michael Thurman, S. Michael Linhart Jan 2001

Occurrence Of Cyanazine Compounds In Groundwater: Degradates More Prevalent Than The Parent Compound, Dana Kolpin, E. Michael Thurman, S. Michael Linhart

United States Geological Survey: Staff Publications

A recently developed analytical method using liquid chromatography/mass spectrometry was used to investigate the occurrence of cyanazine and its degradates cyanazine acid (CAC), cyanazine amide (CAM), deethylcyanazine (DEC), and deethylcyanazine acid (DCAC) in groundwater. This research represents some of the earliest data on the occurrence of cyanazine degradates in groundwater. Although cyanazine was infrequently detected in the 64 wells across Iowa sampled in 1999, cyanazine degradates were commonly found during this study. The most frequently detected cyanazine compound was DCAC (32.8%) followed by CAC (29.7%), CAM (17.2%), DEC (3.1%), and cyanazine (3.1%). The frequency of detection for cyanazine or one …


Effect Of Scale On The Behavior Of Atrazine In Surface Waters, Paul Capel, Steven Larson Jan 2001

Effect Of Scale On The Behavior Of Atrazine In Surface Waters, Paul Capel, Steven Larson

United States Geological Survey: Staff Publications

Field runoff is an important transport mechanism by which agricultural pesticides, including atrazine, move into the hydrologic environment. Atrazine is chosen because it is widely used, is transported in runoff relatively easily, is widely observed in surface waters, and has relatively little loss in the stream network. Data on runoff of atrazine from experimental plot and field studies is combined with annual estimates of load in numerous streams and rivers, resulting in a data set with 408 observations that span 14 orders of magnitude in area. The load as a percent of use (LAPU) on an annual basis is the …


Effects Of Landsat 5 Thematic Mapper And Landsat 7 Enhanced Thematic Mapper Plus Radiometric And Geometric Calibrations And Corrections On Landscape Characterization, James E. Vogelmann, Dennis Helder, Ron Morfitt, Michael J. Choate, James W. Merchant, Henry Bulley Jan 2001

Effects Of Landsat 5 Thematic Mapper And Landsat 7 Enhanced Thematic Mapper Plus Radiometric And Geometric Calibrations And Corrections On Landscape Characterization, James E. Vogelmann, Dennis Helder, Ron Morfitt, Michael J. Choate, James W. Merchant, Henry Bulley

United States Geological Survey: Staff Publications

The Thematic Mapper (TM) instruments on board Landsats 4 and 5 provide high-quality imagery appropriate for many different applications, including land cover mapping, landscape ecology, and change detection. Precise calibration was considered to be critical to the success of the Landsat 7 mission and, thus, issues of calibration were given high priority during the development of the Enhanced Thematic Mapper Plus (ETM+). Data sets from the Landsat 5 TM are not routinely corrected for a number of radiometric and geometric artifacts, including memory effect, gain/bias, and interfocal plane misalignment. In the current investigation, the effects of correcting vs. not correcting …


Basicranial Anatomy Of The Living Linsangs Prionodon And Poiana (Mammalia, Carnivora, Viverridae), With Comments On The Early Evolution Of Aeluroid Carnivorans, Robert M. Hunt Jr. Jan 2001

Basicranial Anatomy Of The Living Linsangs Prionodon And Poiana (Mammalia, Carnivora, Viverridae), With Comments On The Early Evolution Of Aeluroid Carnivorans, Robert M. Hunt Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

The living Asian linsang, Prionodon pardicolor, shares marked anatomical similarities in basicranium and dentition with the extinct Oligocene aeluroid, Palaeoprionodon lamandini, from the Quercy fissures, France. The living African linsang, Poiana richardsoni, is similar yet slightly more derived in basicranial traits relative to Prionodon pardicolor, and also has basicranial and dental features indicating a relationship to the living genets (Genetta). The basicranial and auditory anatomy of a series Palaeoprionodon-Prionodon-Poiana can be interpreted as a morphocline showing the progressive alteration of the form of the petrosal and auditory bulla from the plesiomorphic aeluroid state in …


Population Characteristics And Food Habitats Of White Perch (Morone Americana) In Branched Oak, Nebraska, Cara Hodking Jan 2001

Population Characteristics And Food Habitats Of White Perch (Morone Americana) In Branched Oak, Nebraska, Cara Hodking

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Field Trip Guide (For The Nebraska Well Drillers Association) Western Nebraska Geology, J. Cannia, D. Weinert, D. Brost, C. Miller, D. Carlson Jan 2001

Field Trip Guide (For The Nebraska Well Drillers Association) Western Nebraska Geology, J. Cannia, D. Weinert, D. Brost, C. Miller, D. Carlson

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Resource Notes-Academic Year 2000-01 Jan 2001

Resource Notes-Academic Year 2000-01

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


The Great Plains Natural Resources And Environmental Change Survey Report, D. C. Gosselin, R. Levy, D. Geise Jan 2001

The Great Plains Natural Resources And Environmental Change Survey Report, D. C. Gosselin, R. Levy, D. Geise

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Logan County Test Hole Logs, Perry B. Wigley Jan 2001

Logan County Test Hole Logs, Perry B. Wigley

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Results Of Whole-Rock Organic Geochemical Analyses Of The Crp-3 Drillcore, Victoria Land Basin, Antarctica, Richard M. Kettler Jan 2001

Results Of Whole-Rock Organic Geochemical Analyses Of The Crp-3 Drillcore, Victoria Land Basin, Antarctica, Richard M. Kettler

Department of Earth and Atmospheric Sciences: Faculty Publications

Sediments and rocks recovered in CRP-3 coring operations contain minute amounts of organic matter (average 0.3% TOC). TOC contents and C:N ratios are zoned systematically: those rocks encountered at depths greater than 330 meters below sea floor (mbsf) contain less organic matter and have higher TOC:N ratios (after correcting for inorganic N) than do shallower rocks. The only two samples that have TOC values greater than 1% also contain abundant granule to silt-sized particles of coal. The total sulphur contents of these rocks is very low and indicates either that only small amounts of deposited organic matter were labile, or …


Facies Architecture Of The Crp-3 Drillhole, Victoria Land Basin, Antarctica, Christopher R. Fielding, T. R. Naish, K. J. Woolfe Jan 2001

Facies Architecture Of The Crp-3 Drillhole, Victoria Land Basin, Antarctica, Christopher R. Fielding, T. R. Naish, K. J. Woolfe

Department of Earth and Atmospheric Sciences: Faculty Publications

The Cenozoic Victoria Land Basin (VLB) stratigraphic section penetrated by CRP-3 is mostly of Early Oligocene age. It contains an array of lithofacies comprising fine-grained mudrocks, interlaminated and interbedded mudrocks/sandstones, mud-rich and mud-poor sandstones, conglomerates and diamctites that are together interpreted as the products of shallow marine to possibly non-marine environments of deposition, affected by the periodic advance and retreat of tidewater glaciers. This lithofacies assemblage can be readily rationalised using the facies scheme designed originally for CRP-2/2A, and published previously. The uppermost 330 metres below sea floor (mbsf) shows a cyclical arrangement of lithofacies also similar to that recognised …


Depositional Environments For Strata Cored In Crp-3 (Cape Roberts Project), Victoria Land Basin, Antarctica: Palaeoglaciological And Palaeoclimatological Inferences, R. D. Powell, M. G. Laird, T. R. Naish, Christopher R. Fielding, L. A. Krissek, J.J. M. Van Der Meer Jan 2001

Depositional Environments For Strata Cored In Crp-3 (Cape Roberts Project), Victoria Land Basin, Antarctica: Palaeoglaciological And Palaeoclimatological Inferences, R. D. Powell, M. G. Laird, T. R. Naish, Christopher R. Fielding, L. A. Krissek, J.J. M. Van Der Meer

Department of Earth and Atmospheric Sciences: Faculty Publications

Cape Roberts Project drill core 3 (CRP-3) was obtained from Roberts ridge, a sea-floor high located at 77oS, 12 km offshore from Cape Roberts in western McMurdo Sound, Antarctica. The recovered core is about 939 m long and comprises strata dated as being early Oligocene (possibly latest Eocene) in age, resting unconformably on ~116 m of basement rocks consisting of Palaeozoic Beacon Supergroup sediments. The core includes ten facies commonly occurring in five major associations that are repeated in particular sequences throughout the core and which are interpreted as representing different depositional environments through time. Depositional systems inferred …


Comparison Of Interannual Snowmelt-Onset Dates With Atmospheric Conditions, Sheldon D. Drobot, Mark R. Anderson Jan 2001

Comparison Of Interannual Snowmelt-Onset Dates With Atmospheric Conditions, Sheldon D. Drobot, Mark R. Anderson

Department of Earth and Atmospheric Sciences: Faculty Publications

The snowmelt-onset date represents an important transitional point in the Arctic surface energy balance, when albedo decreases and energy absorption increases rapidly in response to the appearance of liquid water. Interannual variations in snowmelt onset are likely related to large-scale variations in atmospheric circulation, such as described by the Arctic Oscillation (AO). This research therefore examines the relationship between monthly-averaged AO values and mean annual snowmelt-onset dates over Arctic sea ice in 13 regions, from 1979 to 1998. The objective is to statistically relate variations in mean annual regional snowmelt-onset dates to variations in the AO. Additionally, monthly-averaged 500 hPa …


The Onset Of Arctic Sea-Ice Snowmelt As Detected With Passive- And Active-Microwave Remote Sensing, Richard R. Forster, David G. Long, Kenneth C. Jezek, Sheldon D. Drobot, Mark R. Anderson Jan 2001

The Onset Of Arctic Sea-Ice Snowmelt As Detected With Passive- And Active-Microwave Remote Sensing, Richard R. Forster, David G. Long, Kenneth C. Jezek, Sheldon D. Drobot, Mark R. Anderson

Department of Earth and Atmospheric Sciences: Faculty Publications

Daily acquisitions from satellite microwave sensors can be used to observe the spatial and temporal characteristics of the Arctic sea-ice snowmelt onset because the initial presence of liquid water in a dry snowpack causes a dramatic change in the active and passive-microwave response. A daily sequence of backscatter coefficient images from the NASA scatterometer (NSCAT) clearly shows the spatially continuous progression of decreasing backscatter associated with snowmelt onset across the Arctic Ocean during spring 1997. A time series of the active NSCAT backscatter and a scattering index from the passive Special Sensor Microwave/Imager (SSM/I) show similar trends during the time …


Spatial And Temporal Variability In Snowmelt Onset Over Arctic Sea Ice, Mark R. Anderson, Sheldon D. Drobot Jan 2001

Spatial And Temporal Variability In Snowmelt Onset Over Arctic Sea Ice, Mark R. Anderson, Sheldon D. Drobot

Department of Earth and Atmospheric Sciences: Faculty Publications

Climate models suggest surface warming in the Arctic will be rapid and pronounced, implying substantial changes in snowmelt onset are likely. This research therefore examines spatial and temporal variability in passive-microwave derived snowmelt-onset dates over Arctic sea ice. The objectives are to understand better the regional characteristics of snowmelt and to document whether the snowmelt-onset record shows signs of climate change. Snowmelt-onset dates are derived with Scanning Multichannel Microwave Radiometer and Special Sensor Microwave/Imager brightness-temperature data, and they are subsequently stratified into 13 regions to analyze spatial and temporal variability. Results illustrate significant spatial variability in snowmelt onset, with the …


Drawdown And Stream Depletion Produced By Pumping In The Vicinity Of A Partially Penetrating Stream, James J. Butler Jr., Vitaly A. Zlotnik, Ming-Shu Tsou Jan 2001

Drawdown And Stream Depletion Produced By Pumping In The Vicinity Of A Partially Penetrating Stream, James J. Butler Jr., Vitaly A. Zlotnik, Ming-Shu Tsou

Department of Earth and Atmospheric Sciences: Faculty Publications

Commonly used analytical approaches for estimation of pumping-induced drawdown and stream depletion are based on a series of idealistic assumptions about the stream-aquifer system. Anew solution has been developed for estimation of drawdown and stream depletion under conditions that are more representative of those in natural systems (finite width stream of shallow penetration adjoining an aquifer of limited lateral extent). This solution shows that the conventional assumption of a fully penetrating stream will lead to a significant overestimation of stream depletion (> 100%) in many practical applications. The degree of overestimation will depend on the value of the stream leakance …


Chemical And Biological Trends During Lake Evolution In Recently Deglaciated Terrain, Daniel R. Engstrom, Sherilyn C. Fritz, James E. Almendinger, Stephen Juggins Nov 2000

Chemical And Biological Trends During Lake Evolution In Recently Deglaciated Terrain, Daniel R. Engstrom, Sherilyn C. Fritz, James E. Almendinger, Stephen Juggins

Department of Earth and Atmospheric Sciences: Faculty Publications

As newly formed landscapes evolve, physical and biological changes occur that are collectively known as primary succession. Although succession is a fundamental concept in ecology, it is poorly understood in the context of aquatic environments. The prevailing view is that lakes become more enriched in nutrients as they age, leading to increased biological production. Here we report the opposite pattern of lake development, observed from the water chemistry of lakes that formed at various times within the past 10,000 years during glacial retreat at Glacier Bay, Alaska. The lakes have grown more dilute and acidic with time, accumulated dissolved organic …


Intensification Of The Northeast Pacific Oxygen Minimum Zone During The Bolling-Allerod Warm Period, Yan Zheng, Alexander Van Green, Robert F. Anderson, James V. Gardner, Walter E. Dean Oct 2000

Intensification Of The Northeast Pacific Oxygen Minimum Zone During The Bolling-Allerod Warm Period, Yan Zheng, Alexander Van Green, Robert F. Anderson, James V. Gardner, Walter E. Dean

United States Geological Survey: Staff Publications

Although climate records from several locations around the world show nearly synchronous and abrupt changes, the nature of the inferred teleconnection is still poorly understood. On the basis of preserved laminations and molybdenum enrichments in open margin sediments we demonstrate that the oxygen content of northeast Pacific waters at 800 m depth during the Bolling-Allerod warm period (15-13 kyr) was greatly reduced. Existing oxygen isotopic records of benthic and planktonic foraminifera suggest that this was probably due to suppressed ventilation at higher latitudes of the North Pacific. Comparison with ventilation records for the North Atlantic indicates an antiphased pattern of …


Field Trip Guide (For The Nebraska Well Drillers Association) Eastern Nebraska Geology, Scott Summerside, Duane Eversoll, Mark Kuzila, Matt Joeckel Sep 2000

Field Trip Guide (For The Nebraska Well Drillers Association) Eastern Nebraska Geology, Scott Summerside, Duane Eversoll, Mark Kuzila, Matt Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Arthur County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 3, Robert F. Diffendal Jr., James W. Goeke Sep 2000

Arthur County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 3, Robert F. Diffendal Jr., James W. Goeke

Robert F. Diffendal, Jr., Publications

In 1930, the Conservation and Survey Division (CSD) of the University of Nebraska and the United States Geological Survey began a program of cooperative groundwater studies in Nebraska. Since then test drilling by use of rotary drilling equipment has been an integral part of that program. This report contains logs of all the test holes drilled in Arthur County under the program as well as those drilled by the Conservation and Survey Division with financial assistance from other government agencies.

The maps in this report show the locations of all test holes drilled in the county since 1934.

Present techniques …


Ecology Of Elk In The Pine Ridge Region Of Northwestern Nebraska: Seasonal Distribution, Characteristics Of Wintering Sites, And Herd Health, Michael A. Cover Aug 2000

Ecology Of Elk In The Pine Ridge Region Of Northwestern Nebraska: Seasonal Distribution, Characteristics Of Wintering Sites, And Herd Health, Michael A. Cover

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

No abstract provided.


Keith County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 51, Robert F. Diffendal Jr., James W. Goeke Jul 2000

Keith County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 51, Robert F. Diffendal Jr., James W. Goeke

Robert F. Diffendal, Jr., Publications

In 1930, the Conservation and Survey Division (CSD) of the University of Nebraska and the U.S. Geological Survey began a program of cooperative groundwater studies in Nebraska. Since then test drilling by use of rotary drilling equipment has been an integral part of that program. This report contains logs of all the test holes drilled in the county under the program as well as those drilled by the Conservation and Survey Division with financial assistance from other government agencies.

The maps in this report show the locations of all test holes drilled in the county since 1934 (Figure la–d).

Present …


Shifts In Mid- To Late-Holocene Anion Composition In Elk Lake (Grant County, Minnesota): Comparison Of Diatom And Ostracode Inferences, Jasmine E. Saros, Sherilyn C. Fritz, Alison J. Smith May 2000

Shifts In Mid- To Late-Holocene Anion Composition In Elk Lake (Grant County, Minnesota): Comparison Of Diatom And Ostracode Inferences, Jasmine E. Saros, Sherilyn C. Fritz, Alison J. Smith

Department of Earth and Atmospheric Sciences: Faculty Publications

The fossil diatom record from Elk Lake (Grant County, Minnesota) was used to reconstruct salinity and brine type between 2640 and 4645 14C yr BP. This lake was selected for a brine-type reconstruction because a previous study using fossil-ostracode assemblages indicated a shift in anion composition during the mid-Holocene (Smith et al., 1997). Salinity was reconstructed using a transfer function developed for the Northern Great Plains (NGP) of North America; the reconstruction revealed that salinity was higher (1.5–6.2 g l−1) between ~4000 and 4645 14C yr BP and dropped to 0.35–1.2 g l−1 after 4000 14C yr …


Parent Brine Of The Castile Evaporites (Upper Permian), Texas And New Mexico, Walter E. Dean, Douglas W. Kirkland, Rodger E. Denison May 2000

Parent Brine Of The Castile Evaporites (Upper Permian), Texas And New Mexico, Walter E. Dean, Douglas W. Kirkland, Rodger E. Denison

United States Geological Survey: Staff Publications

The Upper Permian (lower Ochoan) Castile Formation is a major evaporite sequence (~10,000 km3) of calcite, anhydrite, and halite in west Texas and southeastern New Mexico. Traditionally the Castile brine has been considered to have been derived from seawater. This tradition has recently been challenged by two versions of the closed-basin drawdown model. They call for deposition from a mixed brine, in part marine and in large part nonmarine. They propose drawdown of as much as 500 m to form a major sink for ground water issuing from the surrounding Capitan reef complex. A large fraction of the …


Changes In Primary Production Of Pawnee Reservoir As A Result Of Reservoir Aging, Kristopher A. Fischer May 2000

Changes In Primary Production Of Pawnee Reservoir As A Result Of Reservoir Aging, Kristopher A. Fischer

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

No abstract provided.


Field Trip Guide For The Upper Republican And Middle Republican Nrd's Southwestern Nebraska Geology And Soils, Duane Eversoll, Jim Goeke, Mark Kuzila Mar 2000

Field Trip Guide For The Upper Republican And Middle Republican Nrd's Southwestern Nebraska Geology And Soils, Duane Eversoll, Jim Goeke, Mark Kuzila

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Hydrologic Variation In The Northern Great Plains During The Last Two Millennia, Sherilyn C. Fritz, Emi Ito, Zicheng Yu, Kathleen R. Laird, Daniel R. Engstrom Mar 2000

Hydrologic Variation In The Northern Great Plains During The Last Two Millennia, Sherilyn C. Fritz, Emi Ito, Zicheng Yu, Kathleen R. Laird, Daniel R. Engstrom

Department of Earth and Atmospheric Sciences: Faculty Publications

Reconstructions of lake-water salinity at decadal resolution for the last 2,000 years are compared among three lakes in North Dakota to infer regional patterns of drought. The intersite comparisons are used to distinguish local variation in climate or hydrology from regional patterns of change. At one lake, diatom-inferred salinity and lake-water Mg/Ca inferred from ostracode shell chemistry are coherent, both in terms of direction and magnitude of change, indicating that each is a robust technique for reconstructing lake-water chemistry. The data show that the last 2,000 years have been characterized by frequent shifts between high and low salinity, suggesting shifts …


Dynamic Fluvial Systems And Gravel Progradation In The Himalayan Foreland, Nicholas Brozovic, Douglas W. Burbank Mar 2000

Dynamic Fluvial Systems And Gravel Progradation In The Himalayan Foreland, Nicholas Brozovic, Douglas W. Burbank

Daugherty Water for Food Global Institute: Faculty Publications

Although the large-scale stratigraphy of many terrestrial foreland basins is punctuated by major episodes of gravel progradation, the relationships of such facies to hinterland tectonism and climate change are often unclear. Structural reentrants provide windows into older and more proximal parts of the foreland than are usually exposed, and thus provide key insights to earlier phases of foreland evolution. Our magnetostratigraphic studies show that, although the major lithofacies preserved within the Himachal Pradesh structural reentrant in northwestern India resemble Neogene facies in Pakistan, they have a much greater temporal and spatial variability. From 11.5 to 7 Ma, major facies boundaries …