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Integrated Management Of Striga Hermonthica, Stemborers, And Declining Soil Fertility In Western Kenya, B. Vanlauwe, F. Kanampiu, G. D. Odhiambo, H. De Groote, L. J. Wadhams, Z. R. Khan May 2008

Integrated Management Of Striga Hermonthica, Stemborers, And Declining Soil Fertility In Western Kenya, B. Vanlauwe, F. Kanampiu, G. D. Odhiambo, H. De Groote, L. J. Wadhams, Z. R. Khan

All Peer-Reviewed Publications

Striga hermonthica (Delile) Benth., stemborers, and declining soil fertility are serious threats to sustainable food production in the Lake Victoria zone of Kenya. To address these constraints, promising integrated crop management technologies were evaluated, using a multi-locational design in four sub-locations in Siaya and Vihiga district (western Kenya) for six cropping seasons. Technologies evaluated consisted of the traditional maize (Zea mays L.) - bean (Phaseolus vulgaris L.) intercrop, maize - Desmodium (Desmodium uncinatum (Jacq.) DC.) push-pull intercrop, Crotalaria (Crotalaria ochroleuca G. Don) - maize rotation, and soybean (Glycine max (L.) Merr) - maize rotation. Within each of these systems, imazapyr-coated …


Evaluation Of A Pilot-Scale Constructed Wetland Treatment System For Ash Basin Water, Lane Dorman May 2008

Evaluation Of A Pilot-Scale Constructed Wetland Treatment System For Ash Basin Water, Lane Dorman

All Theses

This investigation examined the feasibility of using surface-flow constructed wetland treatment systems (CWTSs) to decrease the concentration and bioavailability of targeted constituents of concern (COC) in ash basin water. Ash basin water results from hydraulic transport (sluicing) of coal ash produced during thermoelectric power production. During the sluicing process, potentially toxic trace elements contained within coal ash may be transferred to the aqueous phase and subsequently introduced to aquatic receiving systems. COC in ash basin water were identified by a risk quotient method in order to determine biogeochemical conditions needed within wetland reactors for reducing the aqueous concentration and bioavailability …


Refining Models Of Crustal Growth And Evolution In Southwestern Laurentia With Paired U-Pb And Lu-Hf Analyses Of Igneous And Detrital Zircon, Mark E. Holland May 2008

Refining Models Of Crustal Growth And Evolution In Southwestern Laurentia With Paired U-Pb And Lu-Hf Analyses Of Igneous And Detrital Zircon, Mark E. Holland

Earth and Planetary Sciences ETDs

The origin and evolution of continental crust is a fundamental and debated topic in geoscience. For over thirty years, Proterozoic crust of the southwestern United States has been a field laboratory for studying orogenic processes in the middle crust, and the growth of continental lithosphere via accretionary orogenesis. Three distinct crustal provinces are delineated based on differences in isotopic, structural, and geochronologic characteristics. To address questions about the origin of each province, this dissertation is composed of three chapters that present new U-Pb and Lu-Hf isotope analysis of plutonic, volcanic, and detrital zircon from the oldest known rocks in each …


Foundations And Interpretations Of Quantum Mechanics, Cory Johnson May 2008

Foundations And Interpretations Of Quantum Mechanics, Cory Johnson

Honors Theses

The first famous thought experiment of Einstein gives rise to his theories of relativity, the bedrock of modern astrophysics and cosmology. His second famous thought experiment begins the investigation into the foundations of quantum mechanics. It leads to a paradox, inspiring various 'no-go' theorems proven by Bell, Kochen, and Specker. Physicists and philosophers worldwide become increasingly dissatisfied with the probabilistic complementarity interpretation (Born-Bohr) and eventually offer their own accounts of the theory. By the end of the 20th century two alternative approaches stand out as the best candidates: Both the hidden variables interpretation (de Broglie-Bohm) and the many worlds interpretation …


Effects Of Context Of Natural And Artifactual Objects On Categorization, Linsey Walker May 2008

Effects Of Context Of Natural And Artifactual Objects On Categorization, Linsey Walker

Honors Theses

Categorization of animals and vehicles in different contexts was investigated in three experiments using event related potentials (ERPs). The presence of a background and congruency of the background in relation to the object were both manipulated in order to determine the effects of context on visual processing. In Experiment 1, adults were presented with images of animals and vehicles in two conditions: situated in a congruent context (e.g. an animal in a field) and in the absence of a context (an animal in a white homogeneous background). In experiment 2, adults were presented with images of animals and vehicles in …


Application Of Time-Lapse Ert Imaging To Watershed Characterization, Carlyle R. Miller, Partha S. Routh, Troy R. Brosten, James P. Mcnamara May 2008

Application Of Time-Lapse Ert Imaging To Watershed Characterization, Carlyle R. Miller, Partha S. Routh, Troy R. Brosten, James P. Mcnamara

Geosciences Faculty Publications and Presentations

Time-lapse electrical resistivity tomography (ERT) has many practical applications to the study of subsurface properties and processes. When inverting time-lapse ERT data, it is useful to proceed beyond straightforward inversion of data differences and take advantage of the time-lapse nature of the data. We assess various approaches for inverting and interpreting time-lapse ERT data and determine that two approaches work well. The first approach is model subtraction after separate inversion of the data from two time periods, and the second approach is to use the inverted model from a base data set as the reference model or prior information for …


Impacts Of Human Physical Disturbance Of Benthic Communities In Tributaries Of The Niobrara National Scenic River, Kimberly D. Laing May 2008

Impacts Of Human Physical Disturbance Of Benthic Communities In Tributaries Of The Niobrara National Scenic River, Kimberly D. Laing

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

No abstract provided.


Geochemical Investigation Of Tungsten In Two Groundwater Flow Systems: The Carrizo Sand Aquifer, Texas, Usa, And The Aquia Aquifer, Maryland, Usa, Heeral B. Dave May 2008

Geochemical Investigation Of Tungsten In Two Groundwater Flow Systems: The Carrizo Sand Aquifer, Texas, Usa, And The Aquia Aquifer, Maryland, Usa, Heeral B. Dave

Earth & Environmental Sciences Theses - Archive

Groundwater sampled were collected from well sites located within the Carrizo Sand aquifer in Atascosa and McMullen counties in Texas, and also within the Aquia Aquifer, Maryland in the counties of Queen Anne's, Kent, and Ann Arundel in Maryland. During the field sampling trips, on site measurements were conducted for pH, specific conductance, temperature, alkalinity, dissolved oxygen (DO), oxidation-reduction potential (Eh), iron speciation ([Fe (II)/ Fe(III)]), and dissolved S (-II) concentrations. In order to examine and study solid phase tungsten concentrations in the Aquia (archived at the Maryland Geological Survey) and Carrizo Aquifer sediments, we collected a number of aliquots, …


A Post-Project Assessment Of The Provo River Restoration Project: Channel Design, Reconfiguration, And The Re-Establishment Of Critical Physical Processes, Randy Ray Goetz May 2008

A Post-Project Assessment Of The Provo River Restoration Project: Channel Design, Reconfiguration, And The Re-Establishment Of Critical Physical Processes, Randy Ray Goetz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A physical assessment of the Provo River Restoration Project was undertaken in order to determine how alterations to the channel were designed, the nature of as-built channel morphology, and the performance of the reconfigured channel in terms of achieving frequent (2-year recurrence) bankfull discharge and increasing transient storage. Measures of channelized and reconfigured channel morphology were obtained using total station survey, digital aerial photography, and pebble counts. Results of geomorphic analysis were compared with similar measurements made by a regional consulting company, and stream channel design data, in order to determine that intended mitigation included reducing channel capacity, increasing sinuosity, …


Records Of Natural Fires And The Sorption Of Polycyclic Aromatic Hydrocarbons (Pahs) By Black Carbon And Carbon Chars In Sediments From Oriole Lake (Sequoia National Park), Kevyn Bollinger May 2008

Records Of Natural Fires And The Sorption Of Polycyclic Aromatic Hydrocarbons (Pahs) By Black Carbon And Carbon Chars In Sediments From Oriole Lake (Sequoia National Park), Kevyn Bollinger

Senior Honors Projects

This project investigates the interaction between Black Carbon and Polycyclic Aromatic Hydrocarbons (PAHs) in lake sediments from Oriole Lake in Sequoia National Park California. The interaction between Black Carbon and PAHs is of interest because little is known with respect to the availability and the time scale within which black carbon adsorbs PAHs in a natural system. Black Carbon and PAHs both will eventually be degraded in the environment but the relevant timescales of sorption and degradation are unknown. Field work for this project was conducted July 16-21, 2007 at Oriole Lake in Sequoia National Park California. Sequoia National Park …


Regional Co2 Sequestration Potential – Field Validation Tests, University Of North Dakota. Energy And Environmental Research Center May 2008

Regional Co2 Sequestration Potential – Field Validation Tests, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about the four field validation tests conducted by the Plains CO2 Reduction (PCOR) Partnership to test the efficacy of CO2 sequestration. The project was included in Phase II of the U.S. Department of Energy’s Regional Carbon Sequestration Partnership Initiative. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]


Geology Of The Southern Reveille Range, Nye County, Nevada, Matthew Alan Mckelvey May 2008

Geology Of The Southern Reveille Range, Nye County, Nevada, Matthew Alan Mckelvey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Reveille Range in central Nevada provides a unique window into the mid-Miocene geology and volcanology of the central Great Basin during the "ignimbrite flare up." Although faulted along its margins, the interior of the range is relatively undeformed thus preserving volcanic centers. The Reveille Range contains three mid-Miocene caldera complexes. Previous studies have identified the Goblin Knobs caldera (25.6 Ma) in the central Reveille Range and the caldera of northern Reveille Range (25.3 Ma) to the north. These calderas are completely filled with intracaldera tuffs. This study has identified a younger third caldera located in the southern part of …


Imaging The Southern Trace Of The Black Hills Fault, Clark County, Nevada, Shelley A. Zaragoza May 2008

Imaging The Southern Trace Of The Black Hills Fault, Clark County, Nevada, Shelley A. Zaragoza

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Black Hills fault (BHF) is a SE-dipping normal fault forming the northwestern structural boundary of the Eldorado basin, ∼20 km southeast of Las Vegas, Nevada (Langenheim and Schmidt, 1996). The fault offsets Holocene strata and is thus considered to be active (Fossett, 2005). Therefore, the BHF poses a significant seismic hazard to the greater Las Vegas area.

Fossett (2005) estimated that the BHF is capable of producing a M W 6.4 to 6.8 earthquake. However, this suggests a subsurface rupture length greater than the scarp length (Fossett, 2005). To test this hypothesis, remote sensing, geologic mapping, and high-resolution seismic …


Assessing The Impact Of Water Harvesting On Water Resources, Jennifer Oblinger May 2008

Assessing The Impact Of Water Harvesting On Water Resources, Jennifer Oblinger

All Theses

Clean water supplies, like all natural resources, are becoming scarce all over the world, but especially in developing countries where special interest groups (such as city governments, commercial farmers, other villages downstream, etc.) fight over water rights. The Foundation for Ecological Security (FES) is a non-government organization in India whose mission is to restore degraded lands through cooperation with rural villages. In order to increase the water supply to the ecosystem, FES constructs water harvesting structures (WHS) which impound rainfall, water that would have otherwise runoff and contributed to erosion, in surface storage. This study was conducted to assess the …


The Lower Permian Wasp Head Formation, Sydney Basin: High-Latitude, Shallow Marine Sedimentation Following The Late Asselian To Early Sakmarian Glacial Event In Eastern Australia, Michael C. Rygel, Christopher R. Fielding, Kerrie L. Bann, Tracy D. Frank, Lauren Birgenheier, Stuart C. Tye May 2008

The Lower Permian Wasp Head Formation, Sydney Basin: High-Latitude, Shallow Marine Sedimentation Following The Late Asselian To Early Sakmarian Glacial Event In Eastern Australia, Michael C. Rygel, Christopher R. Fielding, Kerrie L. Bann, Tracy D. Frank, Lauren Birgenheier, Stuart C. Tye

Department of Earth and Atmospheric Sciences: Faculty Publications

ited during the transition to a non-glacial period following the late Asselian to early Sakmarian glacial event in eastern Australia. This shallow marine, sandstone-dominated unit can be subdivided into six facies associations. (i) The marine sediment gravity flow facies association consists of breccias and conglomerates deposited in upper shoreface water depths. (ii) Upper shoreface deposits consist of cross-stratified, conglomeratic sandstones with an impoverished expression of the Skolithos Ichnofacies. (iii) Middle shoreface deposits consist of hummocky cross-stratified sandstones with a trace fossil assemblage that represents the Skolithos Ichnofacies. (iv) Lower shoreface deposits are similar to middle shoreface deposits, but contain more …


The Analysis Of The Natural Attenuation Of Chlorinated Solvents In Groundwater At The Former Westinghouse Site In Bloomfield, New Jersey, Deborah J. Katchen May 2008

The Analysis Of The Natural Attenuation Of Chlorinated Solvents In Groundwater At The Former Westinghouse Site In Bloomfield, New Jersey, Deborah J. Katchen

Theses, Dissertations and Culminating Projects

Data for a contaminated site in Bloomfield, New Jersey were gathered from the New Jersey Department of Environmental Protection (NJDEP), in order to evaluate the hydrogeological conditions at the site. In particular, the data were analyzed to determine whether: 1) the site is still significantly contaminated, 2) natural attenuation is occurring at the site, and 3) natural attenuation will completely remediate the site in a reasonable period of time. The occurrence and distribution of Trichloroethene (TCE) and its daughter products, Dichloroethene (cis 1,2 DCE) and Vinyl Chloride (VC) show that the site is still contaminated.

It was observed that the …


Contribution Of Recharge Along Regional Flow Paths To Discharge At Ash Meadows, Nevada, Michelle Bushman Apr 2008

Contribution Of Recharge Along Regional Flow Paths To Discharge At Ash Meadows, Nevada, Michelle Bushman

Theses and Dissertations

Springs in the Ash Meadows, Nevada wetland area are discharging groundwater at a high volume that cannot be sustained by local, present-day precipitation and associated recharge. Previous groundwater flow models for this region have required groundwater to flow through complex geology for long distances (160km) through fractures that, in the current stress field, should be closed in many instances in the presumed flow direction. This thesis examines several possible flow paths and evaluates each flow path using chemical and isotopic signatures in the water, as well as geologic and geophysical constraints, and determines that flow from beneath the Yucca Mountain …


Geology Of The Phil Pico Mountain Quadrangle, Daggett County, Utah, And Sweetwater County, Wyoming, Alvin D. Anderson Apr 2008

Geology Of The Phil Pico Mountain Quadrangle, Daggett County, Utah, And Sweetwater County, Wyoming, Alvin D. Anderson

Theses and Dissertations

Geologic mapping in the Phil Pico Mountain quadrangle and analysis of the Carter Oil Company Carson Peak Unit 1 well have provided additional constraints on the erosional and uplift history of this section of the north flank of the Uinta Mountains. Phil Pico Mountain is largely composed of the conglomeratic facies of the early Eocene Wasatch and middle to late Eocene Bridger Formations. These formations are separated by the Henrys Fork fault which has thrust Wasatch Formation next to Bridger Formation. The Wasatch Formation is clearly synorogenic and contains an unroofing succession from the adjacent Uinta Mountains. On Phil Pico …


Modern Nutrient Limitation And Geologic Record Of Organic Matter Sources In The Bioluminescent Bays Of Vieques, Puerto Rico, Erin Algeo Apr 2008

Modern Nutrient Limitation And Geologic Record Of Organic Matter Sources In The Bioluminescent Bays Of Vieques, Puerto Rico, Erin Algeo

Earth and Environmental Geosciences Student Honors Theses

The factors contributing to the success of the bioluminescent dinoflagellate, Pyrodinium bahamense var. bahamense in the bays of Vieques, Puerto Rico, are not fully understood, although the dinoflagellate’s success is closely tied to its environment and the nutrients within that environment. Exploring the present and past nutrient concentrations and sources of organic material within the bioluminescent bays of Vieques assists in determining the status of and potential threat to the population of Pyrodinium bahamense var. bahamense. Modern carbon, nitrogen, and phosphorus nutrient concentrations were measured, primarily in the seagrass Thalassia testudinum, to evaluate the distribution and potential limitation of those …


Provenance Analysis Of The Cretaceous Pythian Cave Conglomerate, Northern California, Gregory Alan Augsburger Apr 2008

Provenance Analysis Of The Cretaceous Pythian Cave Conglomerate, Northern California, Gregory Alan Augsburger

Earth and Environmental Geosciences Student Honors Theses

Reconstructions of the Mesozoic paleogeography of the North American Cordillera depend on data that can link displaced terranes to each other and/or to the North American craton. The Pythian Cave Conglomerate (PCC) sits unconformably on the eastern terranes of the Klamath Mountains south of Yreka, California and has the potential to yield valuable information about the tectonic history of the region. The PCC is approximately 60 m thick, with the lower 40 m dominated by cobble conglomerate with thin sandstone lenses, and the upper 20 m containing thicker and more laterally continuous interbedded sandstone layers. Originally interpreted as Tertiary conglomerate …


Provenance Analysis Of The Cretaceous Hornbrook Formation Of Northern California And Southern Oregon, Emily J. Beverly Apr 2008

Provenance Analysis Of The Cretaceous Hornbrook Formation Of Northern California And Southern Oregon, Emily J. Beverly

Earth and Environmental Geosciences Student Honors Theses

The provenance of the Cretaceous Hornbrook Formation, deposited unconformably on the eastern terranes of the Klamath Mountains of northern California and southern Oregon, may prove critical to reconstructing the complex Cretaceous paleogeography of this region. Sandstone petrography from each of the five members of the Hornbrook Formation indicates a variable source region with elements from basement uplift, transitional continent, recycled orogen, and dissected arc sources. A conglomerate clast count from the Klamath River Conglomerate member is broadly consistent with sandstone petrography, but yielded more quartzite and fewer volcanic clasts than the sand-sized fraction. This reflects the different susceptibility to weathering …


Occurrence And Fate Of Pesticides In Four Contrasting Agricultural Settings In The United States, Gregory V. Steele, Henry M. Johnson, Mark W. Sandstrom, Paul D. Capel, Jack E. Barbash Apr 2008

Occurrence And Fate Of Pesticides In Four Contrasting Agricultural Settings In The United States, Gregory V. Steele, Henry M. Johnson, Mark W. Sandstrom, Paul D. Capel, Jack E. Barbash

United States Geological Survey: Staff Publications

Occurrence and fate of 45 pesticides and 40 pesticide degradates were investigated in four contrasting agricultural settings—in Maryland, Nebraska, California, and Washington. Primary crops included corn at all sites, soybeans in Maryland, orchards in California and Washington, and vineyards in Washington. Pesticides and pesticide degradates detected in water samples from all four areas were predominantly from two classes of herbicides—triazines and chloroacetanilides; insecticides and fungicides were not present in the shallow ground water. In most samples, pesticide degradates greatly exceeded the concentrations of parent pesticide. In samples from Nebraska, the parent pesticide atrazine [6-chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4- diamine] was about the same concentration …


Rapid Evolution In Introduced Species, ‘Invasive Traits’ And Recipient Communities: Challenges For Predicting Invasive Potential, Kenneth D. Whitney, Christopher A. Gabler Apr 2008

Rapid Evolution In Introduced Species, ‘Invasive Traits’ And Recipient Communities: Challenges For Predicting Invasive Potential, Kenneth D. Whitney, Christopher A. Gabler

School of Earth, Environmental, & Marine Sciences Faculty Publications

The damaging effects of invasive organisms have triggered the development of Invasive Species Predictive Schemes (ISPS). These schemes evaluate biological and historical characteristics of species and prioritize those that should be the focus of exclusion, quarantine, and/or control. However, it is not clear how commonly these schemes take microevolutionary considerations into account. We review the recent literature and find that rapid evolutionary changes are common during invasions. These evolutionary changes include rapid adaptation of invaders to new environments, effects of hybridization, and evolution in recipient communities. Strikingly, we document 38 species in which the specific traits commonly associated with invasive …


Pesticides In Rain In Four Agricultural Watersheds In The United States, Jason R. Vogel, Michael S. Majewski, Paul D. Capel Apr 2008

Pesticides In Rain In Four Agricultural Watersheds In The United States, Jason R. Vogel, Michael S. Majewski, Paul D. Capel

United States Geological Survey: Staff Publications

Rainfall samples were collected during the 2003 and 2004 growing seasons at four agricultural locales across the USA in Maryland, Indiana, Nebraska, and California. The samples were analyzed for 21 insecticides, 18 herbicides, three fungicides, and 40 pesticide degradates. Data from all sites combined show that 7 of the 10 most frequently detected pesticides were herbicides, with atrazine (70%) and metolachlor (83%) detected at every site. Dacthal, acetochlor, simazine, alachlor, and pendimethalin were detected in more than 50% of the samples. Chlorpyrifos, carbaryl, and diazinon were the only insecticides among the 10 most frequently detected compounds. Of the remaining pesticide …


Using Heat To Characterize Streambed Water Flux Variability In Four Stream Reaches, Hedeff Essaid, Celia M. Zamora, Kathleen A. Mccarthy, Jason R. Vogel, John T. Wilson Apr 2008

Using Heat To Characterize Streambed Water Flux Variability In Four Stream Reaches, Hedeff Essaid, Celia M. Zamora, Kathleen A. Mccarthy, Jason R. Vogel, John T. Wilson

United States Geological Survey: Staff Publications

Estimates of streambed water fl ux are needed for the interpretation of streambed chemistry and reactions. Continuous temperature and head monitoring in stream reaches within four agricultural watersheds (Leary Weber Ditch, IN; Maple Creek, NE; DR2 Drain, WA; and Merced River, CA) allowed heat to be used as a tracer to study the temporal and spatial variability of fluxes through the streambed. Synoptic methods (seepage meter and differential discharge measurements) were compared with estimates obtained by using heat as a tracer. Water flux was estimated by modeling one-dimensional vertical flow of water and heat using the model VS2DH. Flux was …


Transport And Fate Of Nitrate At The Ground-Water/Surface-Water Interface, Larry J. Puckett, Celia Zamora, Hedeff Essaid, John T. Wilson, Henry M. Johnson, Michael Brayton, Jason R. Vogel Apr 2008

Transport And Fate Of Nitrate At The Ground-Water/Surface-Water Interface, Larry J. Puckett, Celia Zamora, Hedeff Essaid, John T. Wilson, Henry M. Johnson, Michael Brayton, Jason R. Vogel

United States Geological Survey: Staff Publications

Although numerous studies of hyporheic exchange and denitrification have been conducted in pristine, high-gradient streams, few studies of this type have been conducted in nutrient-rich, low-gradient streams. This is a particularly important subject given the interest in nitrogen (N) inputs to the Gulf of Mexico and other eutrophic aquatic systems. A combination of hydrologic, mineralogical, chemical, dissolved gas, and isotopic data were used to determine the processes controlling transport and fate of 3− in streambeds at five sites across the USA. Water samples were collected from streambeds at depths ranging from 0.3 to 3 m at three to five …


W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks Apr 2008

W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks

Faculty Publications

A major challenge in the post-genomics era will be to integrate molecular sequence data from extant organisms with morphological data from fossil and extant taxa into a single, coherent picture of phylogenetic relationships; only then will these phylogenetic hypotheses be effectively applied to the study of morphological character evolution. At least two analytical approaches to solving this problem have been utilized: (1) simultaneous analysis of molecular sequence and morphological data with fossil taxa included as terminals in the analysis, and (2) the molecular scaffold approach, in which morphological data are analyzed over a molecular backbone (with constraints that force extant …


Gps Constraints On 34 Slow Slip Events Within The Cascadia Subduction Zone, 1997–2005, Walter Szeliga, Timothy I. Melbourne, Marcelo Santillan, Meghan Miller Apr 2008

Gps Constraints On 34 Slow Slip Events Within The Cascadia Subduction Zone, 1997–2005, Walter Szeliga, Timothy I. Melbourne, Marcelo Santillan, Meghan Miller

Faculty Scholarship for the Cascadia Hazards Institute

Refinements to GPS analyses in which we factor geodetic time series to better estimate both reference frames and transient deformation resolve 34 slow slip events located throughout the Cascadia subduction zone from 1997 through 2005. Timing of transient onset is determined with wavelet transformation of geodetic time series. Thirty continuous stations are included in this study, ranging from northern California to southwestern British Columbia. Our improvements in analysis better resolve the largest creep events and also identify many smaller events. At 48.5 degrees N latitude, a 14-month average recurrence interval has been observed over eight events since 1997. Farther north …


Sustainable Portland: Implementation Series 1, New England Environmental Finance Center Apr 2008

Sustainable Portland: Implementation Series 1, New England Environmental Finance Center

Climate Change

When the Sustainable Portland Task Force Report was released in November 2007, under the leadership of Mayor Jim Cohen, Portland Councilor Kevin Donoghue had the idea that students at the Muskie School of Public Service might be able to help implement recommendations from the report. It may have helped that Kevin was himself a graduate of the Community Planning and Development Master’s program at the Muskie School, but it was a good idea nevertheless. He approached Professor Sam Merrill in the CPD program, who spoke with the new Mayor Ed Suslovic about a possible partnership between the City and the …


Hypogenic Speleogenesis Within Seven Rivers Evaporites: Coffee Cave, Eddy County, New Mexico, Kevin W. Stafford, Lewis Land, Alexander Klimchouk Apr 2008

Hypogenic Speleogenesis Within Seven Rivers Evaporites: Coffee Cave, Eddy County, New Mexico, Kevin W. Stafford, Lewis Land, Alexander Klimchouk

Faculty Publications

Coffee Cave, located in the lower Pecos region of southeastern New Mexico, illustrates processes of hypogenic speleogenesis in the middle Permian Seven Rivers Formation. Coffee Cave is a rectilinear gypsum maze cave with at least four stratigraphically-distinct horizons of development. Morphological features throughout the cave provide unequivocal evidence of hypogenic ascending speleogenesis in a confined aquifer system driven by mixed (forced and free) convection. Morphologic features in individual cave levels include a complete suite that defines original rising flow paths, ranging from inlets for hypogenic fluids (feeders) through transitional forms (rising wall channels) to ceiling half-tube flow features and fluid …