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Nebraska Map Of Counties, Conservation Survey Division Jan 1990

Nebraska Map Of Counties, Conservation Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Annual Report Of Nebraska-1990, Karl E. Starch, Raymond R. Burchett Jan 1990

Annual Report Of Nebraska-1990, Karl E. Starch, Raymond R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Groundwater Levels In Nebraska, 1989, Michael J. Ellis, Gregory V. Steele, Perry B. Wigley Jan 1990

Groundwater Levels In Nebraska, 1989, Michael J. Ellis, Gregory V. Steele, Perry B. Wigley

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Resource Notes-Academic Year 1989-90 Jan 1990

Resource Notes-Academic Year 1989-90

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Diatomaceous Earth Deposits In Nebraska, R. R. Burchett Jan 1990

Diatomaceous Earth Deposits In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Gypsum Deposits In Nebraska, R. R. Burchett Jan 1990

Gypsum Deposits In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Limestone Deposits In Nebraska, R. R. Burchett Jan 1990

Limestone Deposits In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


The Permian System In Nebraska, R. R. Burchett Jan 1990

The Permian System In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Sand And Gravel Deposits In Nebraska, R. R. Burchett Jan 1990

Sand And Gravel Deposits In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Topographic Maps, 1 X 2 Degree Series, R. R. Burchett Jan 1990

Topographic Maps, 1 X 2 Degree Series, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Age Estimates And Uplift Rates For Late Pleistocene Marine Terraces' Southern Oregon Portion Of The Cascadia Forearc, Daniel R. Muhs, Harvey M. Kelsey, Gifford H. Miller, Geoge L. Kennedy, Joseph F. Whelan, Galan W. Mcinelly Jan 1990

Age Estimates And Uplift Rates For Late Pleistocene Marine Terraces' Southern Oregon Portion Of The Cascadia Forearc, Daniel R. Muhs, Harvey M. Kelsey, Gifford H. Miller, Geoge L. Kennedy, Joseph F. Whelan, Galan W. Mcinelly

United States Geological Survey: Staff Publications

Marine terraces are prominent landforms along the southern Oregon coast, which forms part of the forearc region of the Cascadia subduction zone. Interest in the Cascadia subduction zone has increased because recent investigations have suggested that slip along plates at certain types of convergent margins is characteristically accompanied by large earthquakes. In addition, other investigations have suggested that convergent margins can be broadly classified by the magnitude of their uplift rates. With these hypotheses in mind, we generated new uranium series, amino acid, and stable isotope data for southern Oregon marine terrace fossils. These data, along with terrace elevations and …


Sedimentary Paleoenvironments Of Fossil Platyrrhine Localities, Miocene Pinturas Formation, Santa Cruz Province, Argentina, Thomas Bown, Claudio N. Larriestra Jan 1990

Sedimentary Paleoenvironments Of Fossil Platyrrhine Localities, Miocene Pinturas Formation, Santa Cruz Province, Argentina, Thomas Bown, Claudio N. Larriestra

United States Geological Survey: Staff Publications

The Pinturas Formation is a pyroclastic and epiclastic aeolian deposit of Miocene age lying discordantly upon Jurassic rocks in the elevated Andean precordillera of northwest Santa Cruz Province, Argentina. The history of de\'elopment of the Pinturas Formation was significantly affected by the gradual, though sporadic, draping of this aeolian sediment across a profound, slowly filling paleotopography. The Pinturas depositional cycle consisted of: (1) minor aeolian deposition followed by soil formation, and (2) major aeolian deposition followed by intervals of regional erosion. Fluvial action seems to have been almost wholly confined to intraformational erosion, and two significant intraformational erosional unconformities divide …


Phytoplankton Dynamics In Three Rocky Mountain Lakes, Colorado, U.S.A., Diane M. Mcknight, Richard L. Smith, J. Platt Bradbury, Jill S. Baron, Sarah Spaulding Jan 1990

Phytoplankton Dynamics In Three Rocky Mountain Lakes, Colorado, U.S.A., Diane M. Mcknight, Richard L. Smith, J. Platt Bradbury, Jill S. Baron, Sarah Spaulding

United States Geological Survey: Staff Publications

In 1984 and 1985 seasonal changes in phytoplankton were studied in a system of three lakes in Loch Vale, Rocky Mountain National Park, Colorado. Three periods were evident: (1) A spring bloom, during snowmelt, of the planktonic diatom Asterionella Formosa, (2) a mid- summer period of minimal algal abundance, and (3) a fall bloom of the blue-green alga Oscillatoria limnetica. Seasonal phytoplankton dynamics in these lakes are controlled partially by the rapid flushing rate during snowmelt and the transport of phytoplankton from the highest lake to the lower lakes by the stream, Icy Brook. During snowmelt, the A. …


Depositional Environments And Sandstone Diagenesis In The Tyler Formation (Pennsylvanian), Western North Dakota, Larry R. Quandt Jan 1990

Depositional Environments And Sandstone Diagenesis In The Tyler Formation (Pennsylvanian), Western North Dakota, Larry R. Quandt

Theses and Dissertations

Thirty-three oil well cores were examined and approximately 3,100 oil well logs were used to determine the depositional environments of the Tyler Formation (Pennsylvanian) in northwestern North Dakota. Ninety sandstone thin-sections were described and twenty-nine sandstone samples were analyzed by scanning electron microscope/X-ray microanalysis techniques to characterize sandstone diagenesis.

The Tyler Formation in northwestern North Dakota is correlative with the lower unit of the Tyler Formation in southwestern North Dakota. The upper unit of the Tyler Formation in southwestern North Dakota is not present in northwestern North Dakota, contrary to previous workers suggestions. The Tyler Formation in northwestern North Dakota …


A Notch-Strengthening Effect In Fresh-Water Ice, Wilfrid A. Nixon, Erland M. Schulson Jan 1990

A Notch-Strengthening Effect In Fresh-Water Ice, Wilfrid A. Nixon, Erland M. Schulson

Dartmouth Scholarship

Tensile tests have been performed onnotched and unnotched cylindrical samples of randomlyoriented polycrystalline ice of controlled grain-size (between2.2 and 7.3mm) at a loading rate of lOOPaS-l and at a temperature of -10 0c. In the notched samples, the notch-root diameter was 80% of the base diameter. Anotch-strengthening effect was observed in the large-grained ice, with fracture stresses being up to 50% higher than that for unnotched samples of the same grain-size. This notch-strengthening effect diminished as grain-size decreased, disappearing at a grain-size of "'3 mm. The notch-strengthening effect is explained in terms of the triaxial stress constraint at the notch …


Isopoda (Crustacea: Isopoda: Microcharon, Jaera, Proasellus) And Other Fauna In Hypogean Waters Of Southern Cyprus, Boris Sket Jan 1990

Isopoda (Crustacea: Isopoda: Microcharon, Jaera, Proasellus) And Other Fauna In Hypogean Waters Of Southern Cyprus, Boris Sket

International Journal of Speleology

Springs and wells in SW and S part of Cyprus were briefly surveyed. Chlorinity was 0.1 - 0.8 p.p.t. Some isopods were found in collecting galleries of springs and in wells in calcarenites and in gravel deposits. These were Proasellus coxalis ssp. with some depigmented specimens, the probably stygobitic P. c. nanus ssp. n., poorly pigmented Jaera italica, and Microcharon luciae n. sp.; they were accompanied by the stygobitic amphipod Bogidiella cypria, by Turbellaria (Tricladida), by Copepoda (Cyclopoida), and rarely by some other animals (Pisidium sp., Oligochaeta). Only slightly depigmented Turbellaria Tricladida (cf. Dugesia sp.) occur in …


Subsurface And Geochemical Stratigraphy Of Northwestern Oregon, Olga Berenice Lira Jan 1990

Subsurface And Geochemical Stratigraphy Of Northwestern Oregon, Olga Berenice Lira

Dissertations and Theses

Lithological, geophysical, paleontological and geochemical methods were used in order to define the contact relationship between the Keasey and the Cowlitz formations in northwestern Oregon. Drill cuttings from six wells located in Columbia County were analyzed by the Instrumental Neutron Activation Analysis (INAA) method. The concentrations of K, Th, Rb and Sc/Co ratio in the samples established four different groups: 1) High K, Rb, and TH, with low Sc/Co ratio typical of Cowlitz sediments. 2) Low K, Th and Rb and high Sc/Co ratio, more characteristics of the Keasey Formation. 3) Very low concentrations of Rb and high Sc, which …


Lottery Proceeds In California Pay For Installation Of A Ground-Water Monitoring System, June Ann Oberdorfer, J. W. Williams, M. G. Smelser Jan 1990

Lottery Proceeds In California Pay For Installation Of A Ground-Water Monitoring System, June Ann Oberdorfer, J. W. Williams, M. G. Smelser

Faculty Publications

No abstract provided.


Troglobius Coprophagus, A New Genus And Species Of Cave Collembola From Madagascar, With Notes On Its Ecology, José G. Palacios-Vargas, Jane Wilson Jan 1990

Troglobius Coprophagus, A New Genus And Species Of Cave Collembola From Madagascar, With Notes On Its Ecology, José G. Palacios-Vargas, Jane Wilson

International Journal of Speleology

Troglobius coprophagus n. g., n. sp. a cave Collembola from Madagascar is characterized by an elongate and serrate mucro, a non spines dens. Description and illustrations of the new genus and species are given. Some ecological data of this highly cave adapted species is also included.


Two New Niphargus Species (Amphipoda) From Caves In Yugoslavia, Gordan Karaman, Boris Sket Jan 1990

Two New Niphargus Species (Amphipoda) From Caves In Yugoslavia, Gordan Karaman, Boris Sket

International Journal of Speleology

Niphargus numerus sp. n. from the Čavlinska pećina near Obrovac (Dalmatia) and N. factor sp. n. from Vjetrenica (Hercegovina) are described. Both new species from Yugoslav caves belong to the N. transitivus aggregate of species.


Ultrastructure Des Sensilles Cylindriques, Mécanorécepteurs D'Un Crustacé Mysidacé Souterrain, Yves Crouau Jan 1990

Ultrastructure Des Sensilles Cylindriques, Mécanorécepteurs D'Un Crustacé Mysidacé Souterrain, Yves Crouau

International Journal of Speleology

The ultrastructural features of a new chordotonal sensillum in a cavernicolous Mysidacea is described. That sensillum and the other mechanoreceptor sensilla of the same Mysidacea are compared. 9 + 0 cilia show ultrastructural features which previously allowed us to establish a hypothesis with respect to the mode of functioning of chordotonal sensilla. That sensillum shows a pore at the tip of its external receptor.


Laboratory Studies Of Predatory Behaviour In Two Subspecies Of The Carabid Cave Beetle: Neaphaenops Tellkampfi, David M. Griffith Jan 1990

Laboratory Studies Of Predatory Behaviour In Two Subspecies Of The Carabid Cave Beetle: Neaphaenops Tellkampfi, David M. Griffith

International Journal of Speleology

Comparative studies on the foraging behaviour of Neaphaenops tellkampfi tellkampfi and N. t. meridionalis demonstrated adaptation to different environments. The southern subspecies N. t. meridionalis, which is found in wet muddy caves where cave cricket eggs are unlikely prey, did not locate buried cricket eggs and dug fewer and less accurate holes in the lab than the nominate subspecies. N. t. tellkampfi, which reaches high densities in sandy deep cave environments where cricket eggs are the only viable prey, gained significantly greater weight than meridionalis when presented buried cricket eggs as prey. There was no difference with respect …


Secondary Sympatric Occurrence Of Sibling Species Of Subterranean Shrimps In The Karst, M. Cobolli Sbordoni, M. Mattoccia, G. La Rosa, E. De Matthaeis, V. Sbordoni Jan 1990

Secondary Sympatric Occurrence Of Sibling Species Of Subterranean Shrimps In The Karst, M. Cobolli Sbordoni, M. Mattoccia, G. La Rosa, E. De Matthaeis, V. Sbordoni

International Journal of Speleology

Allozyme variation at 32 gene loci was studied in cave dwelling shrimps of the genus Troglocaris (fam. Atyidae). Populations were collected from several caves and wells belonging to different drainage systems in the Karst areas of NE Italy. Results suggest the existence of two sympatric, genetically distinct, biological species (provisionally indicated as species A and B in the T. anophthalmus complex) in the samples collected at the Duino Well, Sagrado and Comarie caves (Nei’s `D= 0.209). Samples from Gradisca and Aurisina are represented by only one (A) or the other (B) of the two species, respectively. Two remaining eastern populations …


Analysis And Numerical Simulation Of The Ground Water System At The Bonneville Navigation Lock Site, Oregon, Dirk Baron Jan 1990

Analysis And Numerical Simulation Of The Ground Water System At The Bonneville Navigation Lock Site, Oregon, Dirk Baron

Dissertations and Theses

As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of the dam. It requires large quantities of water free from chemical and biological contamination. In addition, the water has to be in a narrow temperature range. Currently the fish hatchery receives its water from a well field that is located on the alluvial terrace downstream of Bonneville Dam. The well field lies in the proposed approach channel for the new lock and has to …


Geology Newsletter- 1989, Department Of Geology Dec 1989

Geology Newsletter- 1989, Department Of Geology

Geological and Environmental Sciences News

Vol.1, No. 14

  • Dear Alumni and Friends
  • Geology Development and Scholarship Donations
  • Faculty Briefs
  • News from the Support Staff
  • Geology Earth Science Club
  • Awards & Scholarships
  • 1989 Speakers Program


Dehydration Tolerance Of Several Populus Deltoides Clones, G. Michael Gebre Dec 1989

Dehydration Tolerance Of Several Populus Deltoides Clones, G. Michael Gebre

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

No abstract provided.


Regionalization Of Flood Data Using Probability Distributions And Their Parameters, Nageshwar Rao Bhaskar, Carol Alf O'Connor, Harold Andrew Myers, William Paul Puckett Dec 1989

Regionalization Of Flood Data Using Probability Distributions And Their Parameters, Nageshwar Rao Bhaskar, Carol Alf O'Connor, Harold Andrew Myers, William Paul Puckett

KWRRI Research Reports

The U. S. Geological survey recently used the method of residuals to delineate seven flood regions for the State of Kentucky. As an alternative approach, the FASTCLUS clustering procedure of the Statistical Analysis system (SAS) is used in this study to delineate five to six cluster regions in conjunction with statistical properties of the AMF series, like the coefficient of variation as estimated using method of L-moments, LCV, the parameters of the EVl and GEV flood frequency distributions, and the specific mean annual flood, QSP. For both cluster and USGS flood regions, regionalized flood frequency growth curves are developed and …


Topographic And Volcanic Asymmetry Around The Red Sea: Constraints On Rift Models, Timothy H. Dixon, Erik R. Ivins, Brenda J. Franklin Dec 1989

Topographic And Volcanic Asymmetry Around The Red Sea: Constraints On Rift Models, Timothy H. Dixon, Erik R. Ivins, Brenda J. Franklin

School of Geosciences Faculty and Staff Publications

The Red Sea rift is asymmetric, with the locus of uplift and Tertiary volcanism in Saudi Arabia, 200–400 km east of the present rift axis. One model for this asymmetry involves simple shear extension on an east dipping, low-angle master fault that penetrates the lithosphere. Uplift and volcanism would mark the location where the fault enters the asthenosphere. However, observed seismicity, regional heat flow, and sedimentation are not in accord with this model's predictions. An alternate model involves interaction of upwelling asthenosphere in the early rifting stage with a nearby crustal weak zone such as a suture that controls rift …


Reproductive Biology Of Pinus Sylvestris L.: Seed Yield, Flower Phenology, The Response Of Young Seedlings To Ga 4/7, And Developmental Anatomy, Teresa K. Boes Dec 1989

Reproductive Biology Of Pinus Sylvestris L.: Seed Yield, Flower Phenology, The Response Of Young Seedlings To Ga 4/7, And Developmental Anatomy, Teresa K. Boes

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

No abstract provided.


The Relation Of Radium-226 And 228 To The Groundwater Geochemistry Of Carbon, Sulfur, And Chlorine Near Michigan's Saginaw Bay, Ray Milejczak Dec 1989

The Relation Of Radium-226 And 228 To The Groundwater Geochemistry Of Carbon, Sulfur, And Chlorine Near Michigan's Saginaw Bay, Ray Milejczak

Masters Theses

The Michigan Department of Public Health (MDPH) sampled 149 residential wells producing from glacial drift and Saginaw Formation aquifers in Bay, Midland, Saginaw, and Tuscola counties in 1987. These wells were analyzed for 226Ra, 228Ra and general chemistry. Of the 149 samples, 50 exceeded the USEPA MCL of 5 pCi/L or greater for combined 226Ra + 228Ra activities. A geochemical model (WATEQF, Plummer et al., 1976) was used to determine activity coefficients, activities, ionic strength, and mineral saturation. The radium isotopes were statistically analyzed with respect to the chemical data from MDPH and the geochemical model …