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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 …

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Paleoseismicity Of The North Branch Of The Newport-Inglewood Fault Zone In Huntington Beach, California, From Cone Penetrometer Test Data, Lisa B. Grant, John T. Waggoner, Thomas K. Rockwell, Carmen Von Stein Jan 1997

Paleoseismicity Of The North Branch Of The Newport-Inglewood Fault Zone In Huntington Beach, California, From Cone Penetrometer Test Data, Lisa B. Grant, John T. Waggoner, Thomas K. Rockwell, Carmen Von Stein

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Application of cone penetrometer testing (CPT) is a promising method for studying subsurface fault zones in stratified, unconsolidated sediment where trenching is not feasible. Analysis of data from 72 CPTs, spaced 7.5 to 30.0 m apart, and 9 borings indicates that the North Branch fault, the active strand of the Newport-Inglewood fault zone (NIFZ) in Huntington Beach, has generated at least three and most likely five recognizable surface ruptures in the past 11.7 +/- 0.7 ka. Additional smaller earthquakes similar to the M-w 6.4 1933. Long Beach earthquake may also have occurred but would not be recognizable with this method. …

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Climatic Fluctuations And Tropical Troglobitic Evolution, Pedro Gnaspini Jan 1997

Climatic Fluctuations And Tropical Troglobitic Evolution, Pedro Gnaspini

International Journal of Speleology

No abstract provided.

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A Simple Scenario For Stygobitization In Stenobermuda Schultz, 1978 (Isopoda Asellota Stenetriidae), With Description Of A New Species From Andros Island, Bahamas, Lazare Botosaneanu, Thomas M. Iliffe Jan 1997

A Simple Scenario For Stygobitization In Stenobermuda Schultz, 1978 (Isopoda Asellota Stenetriidae), With Description Of A New Species From Andros Island, Bahamas, Lazare Botosaneanu, Thomas M. Iliffe

International Journal of Speleology

Description of a new stygobitic and troglomorphic species of Stenobermuda from a Blue Hole in the Bahamas, is an opportunity for speculation about hypogean colonization by this and by another cave-dwelling species from Bermuda, starting from populations of a widely distributed Western Atlantic shallow water marine species.

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Geographic Variation And Genetic Relationships In Populations Of The Androniscus Dentiger Complex From Central Italy (Isopoda, Oniscidea, Trichoniscidae), Gabriele Gentile, Giuliana Allegrucci Jan 1997

Geographic Variation And Genetic Relationships In Populations Of The Androniscus Dentiger Complex From Central Italy (Isopoda, Oniscidea, Trichoniscidae), Gabriele Gentile, Giuliana Allegrucci

International Journal of Speleology

Androniscus dentiger is a terrestrial isopod distributed from Great Britain to North Africa, inhabiting humid edafic environments, superficial underground compartments and both natural and artificial caves. In this study allozyme data have been used to investigate the geographic variation and the genetic relationships of several populations of A. dentiger from Central Italy, using as outgroups populations from four congeneric species, A. calcivagus, A. cfr. subterraneus, A. spelaeorum, and A. degener. Multivariate analysis of A. dentiger allele frequencies indicates the existence of a group of populations (group A) distributed in a wide geographic area which are genetically …

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Genetic Divergence And Evolutionary Times: Calibrating A Protein Clock For South-European Stenasellus Species (Crustacea Isopoda), Valerio Ketmaier, Roberto Argano, Marina Cobolli, Elvira De Matthaeis Jan 1997

Genetic Divergence And Evolutionary Times: Calibrating A Protein Clock For South-European Stenasellus Species (Crustacea Isopoda), Valerio Ketmaier, Roberto Argano, Marina Cobolli, Elvira De Matthaeis

International Journal of Speleology

We studied genetic divergence in a group of exclusively stygobiont isopods of the family Stenasellidae. In particular, we assessed evolutionary relationships among several populations of Stenasellus racovitzai and Stenasellus virei. To place this study in a phylogenetic context. we used another species of Stenasellus, S. assorgiai, as an outgroup. S. racovitzai occurs in Corsica, Sardinia and in the fossil islands of the Tuscan Archipelago, while S. virei is a polytypic species widely distributed in the central France and Pyrenean area. This vicariant distribution is believed to be the result of the disjunction of the Sardinia-Corsica microplate from …

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Long Term Stability Of A Terrestrial Cave Community, Claudio Di Russo, Gianmaria Carchini, Mauro Rampini, Marco Lucarelli, Valerio Sbordoni Jan 1997

Long Term Stability Of A Terrestrial Cave Community, Claudio Di Russo, Gianmaria Carchini, Mauro Rampini, Marco Lucarelli, Valerio Sbordoni

International Journal of Speleology

We report data on the spatial structure and seasonal variation of the community of Valmarino cave, a medium sized sandstone cave, located a few kilometres from the coast line, in Central Italy. Due to both its habitat features and its relatively recent geological history, Valmarino cave is only inhabited by terrestrial, troglophilic elements, i.e facultative cave dwellers. By means of monthly censuses and density plot estimates we have investigated species abundance, diversity and their spatial organization, by considering separately samples from different cave sectors. Homogeneous sampling design allowed to compare series of samplings performed in 1974 and 1994. On the …

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Les Deux Faces De La Pensée De E. A. Martel, Jacques Choppy Jan 1997

Les Deux Faces De La Pensée De E. A. Martel, Jacques Choppy

International Journal of Speleology

Réunion de textes de Martel: 1 - Extraits du Nouveau Traité des Eaux Souterraines (1921), donnant l’essentiel de la pensée de l’auteur sur l’hydraulique et la morphologie du karst. 2 - En opposition à cette vision, rappelée de nombreuses fois par l’auteur, extraits de diverses publications (de 1894 à 1930), admettant qu’un fonctionnement en régime noyé était possible: Martel est donc l’un des tout premiers ayant observé des formes de creusement en régime noyé, et les ayant interprétées comme telles.

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The Significance Of E. A. Martel For Speleology In Slovenia, Andrej Kranjc Jan 1997

The Significance Of E. A. Martel For Speleology In Slovenia, Andrej Kranjc

International Journal of Speleology

Three times Martel visited karst in Carniola: in 1879, 1893 and 1896. The importance of his visits and later publications lies in fact that he informed the francophone public about our karst and caves; his visit stimulated the introduction of new technical means into the then Austrian speleology (folding boat, portable telephone); in 1893 due to his researches Postojnska jama became the longest cave in Europe; public found out about existence of caving society Anthron, which was the first Slovene and Slav society of the kind; he set up the foundations of international speleological co-operation and included into it Austrian …

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Martel's Links With Usa, Trevor R. Shaw Jan 1997

Martel's Links With Usa, Trevor R. Shaw

International Journal of Speleology

Of the 29% foreign members in the Société de Spéléologie, five lived in the USA. They were Luella Owen (the only woman member of the Société), R. Ellsworth Cali, H.C. Hovey, E Van Epps and C. R. Blackall. E.S. Balch, though not a member, also knew Martel. These members, between them, published ten papers in Spelunca, which also reviewed their other work. The activities of these six, and their links with France, are discussed. Martel actively encouraged cave work in America, as elsewhere, and Hovey, who had been with him during the survey of Aven Armand, he knew quite well. …

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Martel's Voyage To Russia In 1903, Arrigo A. Cigna Jan 1997

Martel's Voyage To Russia In 1903, Arrigo A. Cigna

International Journal of Speleology

The news concerning caves and karst reported in a Martel’s book on his voyage to Russia in 1903 are here listed and the cave maps are reproduced.

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Edouard-Alfred Martel Et Les Cavernes De La Belgique, Daniel André Jan 1997

Edouard-Alfred Martel Et Les Cavernes De La Belgique, Daniel André

International Journal of Speleology

An exhaustive report on the activity of Martel in Belgium is here given. In particular some relevant passages of Martel’s letters and papers are also included.

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Are Troglobitic Taxa Troglobiomorphic? A Test Using Phylogenetic Inference, Laure Desutter-Grandcolas Jan 1997

Are Troglobitic Taxa Troglobiomorphic? A Test Using Phylogenetic Inference, Laure Desutter-Grandcolas

International Journal of Speleology

Obligate cave dwelling organisms are frequently characterised by a peculiar morphological syndrome, named troglomorphosis or troglobiomorphosis. This hypothesis, which deals with the evolutionary influence of the subterranean environment on cave organisms is far from being universally accepted. Yet it has been adopted by many authors and is often included in the definitions of the current classification of cave taxa. In this paper I present a test of the troglobiomorphosis hypothesis, using the case study of the cricket clade Amphiacustae (Orthoptera, Grylloidea, Phalangopsidae). Such a test preliminarily requires that observations of the habitat of the taxa (achieved on present-day populations) are …

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The Hawaiian Cave Planthoppers (Homoptera: Fulgoroidea: Cixiidae) - A Model For Rapid Subterranean Speciation?, Hannelore Hoch Jan 1997

The Hawaiian Cave Planthoppers (Homoptera: Fulgoroidea: Cixiidae) - A Model For Rapid Subterranean Speciation?, Hannelore Hoch

International Journal of Speleology

After the successful colonization of a single ancestral species in the Hawaiian Islands, planthoppers of the cixiid genus Oliarus underwent intensive adaptive radiation resulting in 80 described endemic species. Oliarus habitats range from montaneous rain forests to dry coastal biotopes and subterranean environments. At least 7 independant evolutionary lines represented by different species have adapted to lava tubes on Molokai (1), Maui (3), and Hawaii Island (3). Behavioral and morphological studies on one of these evolutionary lines on Hawaii Island, the blind, flight- and pigmentless Oliarus polyphentus have provided evidence for reproductive isolation between allopatric populations which may in fact …

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Variations In The Frequency-Magnitude Distribution With Depth In Two Volcanic Areas: Mount St. Helens, Washington, And Mt. Spurr, Alaska, Stefan Wiemer, Stephen R. Mcnutt Jan 1997

Variations In The Frequency-Magnitude Distribution With Depth In Two Volcanic Areas: Mount St. Helens, Washington, And Mt. Spurr, Alaska, Stefan Wiemer, Stephen R. Mcnutt

School of Geosciences Faculty and Staff Publications

The frequency-magnitude distribution of earthquakes, characterized using the b-value, is examined as a function of space beneath Mount St. Helens (1988–1996), and Mt. Spurr (1991–1995). At Mount St. Helens, two volumes of anomalously high b (b > 1.3) can be observed at depths of 2.6–3.6 km below the crater floor and below 6.4 km. These anomalies coincide with (1) the depth of vesiculation of ascending magma, and (2) the suggested location of a magma chamber at Mount St. Helens. Study of Mt. Spurr reveals an area of high b-value (b ≥ 1.3) at a depth of about 2.3–4.5 …

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Observations At Costa Rican Volcano Offer Clues To Causes Of Eruptions, M. Hagerty, S. Y. Schwartz, M. Protti, Timothy H. Dixon, M. Garcés Jan 1997

Observations At Costa Rican Volcano Offer Clues To Causes Of Eruptions, M. Hagerty, S. Y. Schwartz, M. Protti, Timothy H. Dixon, M. Garcés

School of Geosciences Faculty and Staff Publications

Recent measurements of ground deformation at an active volcano show great promise for elucidating the processes that lead to volcanic eruptions. A long-term effort to continuously monitor ground deformation over a very wide bandwidth using state-of-the-art geodetic, seismic, and acoustic instruments at Arenal Volcano in Costa Rica is producing high-quality recordings of harmonic tremor and explosive events and offers an exciting opportunity to explore possible lunar periodicities in volcanic eruptivity.

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Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, S. Olafsen Lackey, Robert F. Diffendal Jr., R. R. Burchett, D. A. Eversoll, R. A. Tremblay Jan 1997

Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, S. Olafsen Lackey, Robert F. Diffendal Jr., R. R. Burchett, D. A. Eversoll, R. A. Tremblay

Conservation and Survey Division: Faculty and Staff Publications

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

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Resource Notes-Academic Year 1996-97 Jan 1997

Resource Notes-Academic Year 1996-97

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Geology Of The Montrose, Orella, Wolf Butte, Roundtop And Horn 7.5' Usgs Quadrangles, Sioux And Dawes Counties, Nebraska, Hannan E. Lagarry, Leigh Anne Lagarry Jan 1997

Geology Of The Montrose, Orella, Wolf Butte, Roundtop And Horn 7.5' Usgs Quadrangles, Sioux And Dawes Counties, Nebraska, Hannan E. Lagarry, Leigh Anne Lagarry

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Fluxes Of Copper-Complexing Ligands From Estuarine Sediments, Stephen A. Skrabal, John R. Donat, David J. Burdige Jan 1997

Fluxes Of Copper-Complexing Ligands From Estuarine Sediments, Stephen A. Skrabal, John R. Donat, David J. Burdige

OES Faculty Publications

Most studies of the organic complexation of Cu in natural waters have focused on distributions and processes in the water column, where a significant fraction of Cu-complexing ligands may be biologically produced. We present direct evidence for a flux of Cu-complexing ligands from estuarine sediments, demonstrating that sediments are a significant, yet previously unrecognized source of the ligands. Fluxes of Cu-complexing ligands from Chesapeake Bay sediments range from 300 to 1,200 nmol m-2 d-1, exceeding fluxes of total dissolved Cu by 3->40-fold, suggesting that any Cu fluxing from the sediments is likely to be organically complexed. …

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Potential For Coastal Flooding Due To Coseismic Subsidence In The Central Cascadia Margin, Elson T. Barnett Jan 1997

Potential For Coastal Flooding Due To Coseismic Subsidence In The Central Cascadia Margin, Elson T. Barnett

Dissertations and Theses

Interpretations made from compilation of existing core and cutbank data for Oregon and Washington are used to evaluate the potential flooding impact from regional coseismic subsidence. Estimates of regional subsidence are based on tidal level indicators including plant macrofossils, peat development, and diatoms. A compilation of existing late Holocene stratigraphic records shows multiple burial events in all bays of Oregon, however some coastal sites in central Oregon show continuous submergence. Tests of tidal level indicators using modern Cascadia wetlands indicate that paleosubsidence can be estimated to 0.0 ± 0.5m, 1.0 ±0.5m, and 2 m ± 0.5m. An AMS date from …

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Grand Tour-Part 2: Petrogenesis And Thermal Evolution Of Deep Continental-Crust: The Record From The East Humboldt Range, Nevada, Allen J. Mcgrew, Mark T. Peters Jan 1997

Grand Tour-Part 2: Petrogenesis And Thermal Evolution Of Deep Continental-Crust: The Record From The East Humboldt Range, Nevada, Allen J. Mcgrew, Mark T. Peters

Department of Earth, Environment and Sustainability Faculty Publications

The northern part of the East Humboldt Range, Nevada, provides a rare opportunity to explore the petrogenetic environment of deep levels in the middle crust during both large-scale Mesozoic contraction and Cenozoic regional extension. On this segment of the field trip, we will explore evidence bearing on the character of the metamorphic and magmatic history of this terrane, and attempt to link these constraints to the rheology and tectonic evolution of the middle crust during the Mesozoic and Cenozoic.

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The Grand Tour Of The Ruby-East Humboldt Metamorphic Core Complex, Northeastern Nevada: Part 1-Introduction & Road Log, Arthur W. Snoke, Keith A. Howard, Allen J. Mcgrew, Bradford R. Burton, Calvin G. Barnes, Mark T. Peters, James E. Wright Jan 1997

The Grand Tour Of The Ruby-East Humboldt Metamorphic Core Complex, Northeastern Nevada: Part 1-Introduction & Road Log, Arthur W. Snoke, Keith A. Howard, Allen J. Mcgrew, Bradford R. Burton, Calvin G. Barnes, Mark T. Peters, James E. Wright

Department of Earth, Environment and Sustainability Faculty Publications

The purpose of this geological excursion is to provide an overview of the multiphase developmental history of the Ruby Mountains and East Humboldt Range, northeastern Nevada. Although these mountain ranges are commonly cited as a classic example of a Cordilleran metamorphic core complex developed through large-magnitude, mid-Tertiary crustal extension, a preceding polyphase Mesozoic contractional history is also well preserved in the ranges. An early phase of this history involved Late Jurassic two-mica granitic magmatism, high-temperature but relatively low-pressure metamorphism, and polyphase deformation in the central Ruby Mountains. In the northern Ruby Mountains and East Humboldt Range, a Late Cretaceous history …

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How Much Ecological Information Is Preserved In Fossil Coral Reefs And How Reliable Is It?, B. J. Greenstein, H. Allen Curran Jan 1997

How Much Ecological Information Is Preserved In Fossil Coral Reefs And How Reliable Is It?, B. J. Greenstein, H. Allen Curran

Geosciences: Faculty Publications

The coral reef fossil record is the exclusive database from which analyses of the response of coral communities to environmental change over geological time scales may be gauged. However, few studies have attempted to ascertain whether the reef fossil record is a reasonably accurate representation of a once living coral community. To address this issue, we have performed a systematic comparison of the taxonomic composition and diversity present in exposure of Pleistocene patch reef and reef tract facies found in the Bahamas to that observed for life and death assemblages currently present in analogous modern reefs of the Florida Keys. …

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Fernandez Bay, San Salvador, Bahamas: A Natural Laboratory For Assessment Of The Preservation Of Coral Reef Community Structure, Benjamin J. Greenstein, Lora A. Harris, H. Allen Curran Jan 1997

Fernandez Bay, San Salvador, Bahamas: A Natural Laboratory For Assessment Of The Preservation Of Coral Reef Community Structure, Benjamin J. Greenstein, Lora A. Harris, H. Allen Curran

Geosciences: Faculty Publications

Reprinted from: James L. Carew (ed.), Proceedings of the 8th Symposium on the Geology of the Bahamas: San Salvador, Bahamian Field Station

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Ichnology Of An Intertidal Carbonate Sand Flat: Pigeon Creek, San Salvador Island, Bahamas, H. Allen Curran, Austin B. Williams Jan 1997

Ichnology Of An Intertidal Carbonate Sand Flat: Pigeon Creek, San Salvador Island, Bahamas, H. Allen Curran, Austin B. Williams

Geosciences: Faculty Publications

Reprinted from: James L. Carew (ed.), May 30–June 3, 1996, Proceedings of the 8th Symposium on the Geology of the Bahamas and Other Carbonate Regions: San Salvador, Bahamian Field Station.

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Bahamian Sangamonian Coral Reefs And Sea-Level Change, Brian White, H. Allen Curran, Mark A. Wilson Jan 1997

Bahamian Sangamonian Coral Reefs And Sea-Level Change, Brian White, H. Allen Curran, Mark A. Wilson

Geosciences: Faculty Publications

Reprinted from James L. Carew (ed.) May 30–June 3, 1996, Proceedings of the 8th Symposium on the Geology of the Bahamas and Other Carbonate Regions: Bahamian Field Station, San Salvador, Bahamas.

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Reexamination Of Scarp Development Along The Niagara Escarpment, Ontario, Canada, David Walter Hintz Jan 1997

Reexamination Of Scarp Development Along The Niagara Escarpment, Ontario, Canada, David Walter Hintz

Theses and Dissertations (Comprehensive)

The Niagara Escarpment is generally viewed as a relict landform which shows ancient structural features and the effects of glaciation. Since it was realized that the Escarpment was not a fault, but instead a feature of erosional origin, little interest has been paid to development of the steep cliffed section of the Niagara Escarpment. This research project has several objectives. The first is an examination of the relationship between the morphology of the Escarpment and its geological units. This will include analysis of the structure and lithology of each and the geochemistry, especially, of the Queeston Formation. Associated with the …

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A Sensitivity Analysis Of The Hydrology Of The Bow Valley Above Banff, Alberta Using The Ubc Watershed Model, Alexi Zawadzki Jan 1997

A Sensitivity Analysis Of The Hydrology Of The Bow Valley Above Banff, Alberta Using The Ubc Watershed Model, Alexi Zawadzki

Theses and Dissertations (Comprehensive)

Snow and ice meltwater constitutes a significant portion of westem Canada's water resources for residential, industrial and agricultural uses. As a consequence, temporal variations in climate will have a marked effect on the local hydrology of the Canadian Rocky Mountains, especially as glaciers, glacierettes and snow packs decrease in size or melt out. It is therefore very important for hydrologists to accurately understand the climatic sensitivity of glacierized watersheds in order to predict and prepare for potentially dramatic variations in the future water budget. This thesis proposes a methodology for the estimation of the hydrological response of a large, temperate, …

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An Assessment Of Hydrological Process And Landform Change: Slave River Delta, Northwest Territories, Ronald Brad Hill Jan 1997

An Assessment Of Hydrological Process And Landform Change: Slave River Delta, Northwest Territories, Ronald Brad Hill

Theses and Dissertations (Comprehensive)

The Slave River Delta, 61˚15'N, 113˚30'W, is located at the mouth of the Slave River in the southeast arm of Canada's Great Slave Lake. Although the delta itself lies some 1600 km downstream from the W.A.C. Bennett Dam at Hudson's Hope, British Columbia, the mean annual discharge and sediment load of the Slave River have decreased by 16% and 33% respectively since regulation. Such alterations in the Slave River flow regime have significant implications for the growth of the River Delta since the transfer of sediment to the delta front is one of the most important factors in the landform’s …

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