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Nebraska Grout Task Force In-Situ Study Of Grout Material 2001 - 2006 And 2007 Dye Tests, Susan Olafsen Lackey, Will F. Myers, Thomas C. Christopherson, Jeffrey J. Gottula Oct 2009

Nebraska Grout Task Force In-Situ Study Of Grout Material 2001 - 2006 And 2007 Dye Tests, Susan Olafsen Lackey, Will F. Myers, Thomas C. Christopherson, Jeffrey J. Gottula

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Evolution Of The Cretaceous Calcareous Nannofossil Genus Eiffellithus And Its Biostratigraphic Significance, J. L. Shamrock, David K. Watkins Oct 2009

Evolution Of The Cretaceous Calcareous Nannofossil Genus Eiffellithus And Its Biostratigraphic Significance, J. L. Shamrock, David K. Watkins

Department of Earth and Atmospheric Sciences: Faculty Publications

The calcareous nannofossil genus Eiffellithus is an important taxon of mid- to Upper Cretaceous marine sediments in biostratigraphy and paleoceanography. The definition of species within Eiffellithus have been both broadly interpreted and variably applied by nannofossil workers. This is particularly true for the Eiffellithus eximius plexus. While the taxonomy of mid-Cretaceous Eiffellithus species has recently been well-defined, the remaining 35 m.y. history of the genus has not been closely examined. Our investigation of Cenomanian to Maastrichtian sediments from the Western Interior Seaway, Gulf of Mexico, and Western Atlantic gives rise to six new species of Eiffellithus that can be reliably …


Indicadores Funcionales Y Estructurales Para Evaluar El Estado De Conservación De Humedales Costeros En El Sur De Tamaulipas, Alejandro Fierro-Cabo Sep 2009

Indicadores Funcionales Y Estructurales Para Evaluar El Estado De Conservación De Humedales Costeros En El Sur De Tamaulipas, Alejandro Fierro-Cabo

School of Earth, Environmental, & Marine Sciences Faculty Publications

El manejo adecuado de las zonas costeras requiere de herramientas que permitan detectar procesos degradantes en los ecosistemas estratégicos prestadores de servicios ambientales. Los indicadores ecológicos responden adecuadamente a esta necesidad en humedales costeros. Se estudiaron ocho humedales de origen y características distintas, con afectaciones contrastantes conocidas. Se seleccionaron los indicadores que mejor discriminaron los sitios y se utilizaron para evaluar la evolución del estado de conservación de los mismos. La correspondencia ecológica entre indicadores funcionales y estructurales no se confirmó en todos los casos, por lo que es necesario utilizar ambos tipos para obtener un mejor diagnóstico. En dicha …


Estimating Debye Parameters From Gpr Reflection Data Using Spectral Ratios, John H. Bradford Sep 2009

Estimating Debye Parameters From Gpr Reflection Data Using Spectral Ratios, John H. Bradford

Geosciences Faculty Publications and Presentations

In the GPR frequency range, electromagnetic wave attenuation is largely controlled by dielectric relaxation processes. A primary relaxation commonly occurs in the 10 – 100 MHz range for many earth materials in which the GPR signal propagates effectively. This relaxation leads to strong nonlinearity in the frequency dependent attenuation and occurs in a frequency range that is often used for groundwater investigations. This non-linearity complicates data analysis but also may provide additional material property information. I investigate inversion for Debye relaxation parameters directly from GPR reflection data, including increasing the bandwidth of the signal by summing the response from 25 …


Towards Mineralogical And Geochemical Reference Groups For Some Bronze Age Ceramics 
From Transylvania (Romania), Volker Hoeck, Corina Ionescu, Lucretia Ghergari, Carmen Precup Sep 2009

Towards Mineralogical And Geochemical Reference Groups For Some Bronze Age Ceramics 
From Transylvania (Romania), Volker Hoeck, Corina Ionescu, Lucretia Ghergari, Carmen Precup

Studia UBB Geologia

Based on their chemical composition ceramic shards from three Bronze Age sites in Transylvania, i.e., Copăceni, Derşida and Palatca respectively, were distinguished by major, trace, and RE elements. Within the Copăceni samples, two subgroups (A and B) showing different chemistry and mineralogy were additionally separated out. The link between chemistry and mineralogy showed clearly the important contribution of the temper to the overall chemistry of the ceramic shards. In turn, the chemistry facilitated the provenance study of the raw materials, which were collected in the vicinity of the sites. In combination with the mineralogy of the ceramics, the chemical analyses …


Soil-Plant Relationship Of Pteropyrum Olivieri, A Serpentine Flora Of Wadh, Balochistan, Pakistan And Its Use In Mineral Prospecting, Shahid Naseem, Erum Bashir, Khaula Shireen, Sheraz Shafiq Sep 2009

Soil-Plant Relationship Of Pteropyrum Olivieri, A Serpentine Flora Of Wadh, Balochistan, Pakistan And Its Use In Mineral Prospecting, Shahid Naseem, Erum Bashir, Khaula Shireen, Sheraz Shafiq

Studia UBB Geologia

Biogeochemical investigation of Pteropyrum olivieri, a flora of Wadh area in perspective of plant-soil-rock relationship has been made. It is a native of Irano-Turanian region which extended into Saharo-Sindian region of Pakistan. The distribution of P. olivieri and some other co-ecological flora in relation to lithology was also discussed. Field observations showed its controlled population on the serpentine soil. The average abundance of Mg and Ca in soil was estimated as 2.43% and 5.46 respectively. The Mg/Ca ratio of the soils of the study area was below unity (0.445), indicating pedogenesis from serpentinite. Quantitative estimation of Cr, Ni, Co and …


Gpr Detection Of Karst And Archaeological Targets Below The Historical Centre Of Merida, Yucatán, Mexico., Luis Barba, Jorge Blancas, Agustin Ortiz, Josep Ligorred Sep 2009

Gpr Detection Of Karst And Archaeological Targets Below The Historical Centre Of Merida, Yucatán, Mexico., Luis Barba, Jorge Blancas, Agustin Ortiz, Josep Ligorred

Studia UBB Geologia

The Historical Center of Merida has been classified as a “zone of high patrimonial value” based on the study of topography and the historical documents that show a long-term occupation, non-interrupted since pre-Columbian times when T’Hó was the great capital of the northern region of the Maya area.

For the local government, rehabilitation of the Historical Center of Merida has been a great priority. Among others, this project includes preservation of archaeological remains (pre-Columbian or colonial) and detection of karstic zones under the city. In order to prevent damage to the patrimony, ground penetrating radar (GPR) surveys were carried out …


Development And Usage Of Geosites: New Results From Research And Conservation Activities In The Piemonte Region (Italy), Luca Ghiraldi, Paola Coratza, Ermanno De Biaggi, Marco Giardino, Mauro Marchetti, Luigi Perotti Sep 2009

Development And Usage Of Geosites: New Results From Research And Conservation Activities In The Piemonte Region (Italy), Luca Ghiraldi, Paola Coratza, Ermanno De Biaggi, Marco Giardino, Mauro Marchetti, Luigi Perotti

Studia UBB Geologia

This paper describes a series of activities carried out by public institutions, whose aim is to identify possible ways of acquiring knowledge and of allowing enjoyment of the Piemonte Region’s geological heritage. The activities concern the inventory, the evaluation, the storage and the publication of information, both alphanumerical and geographical, in relation to geosites. A database accessible directly from Web and a Web-GIS application has been developed in order to supply valuable and comprehensive instruments for both, representing the results of research and promoting the knowledge of the geological heritage to a large number of people.


Decaying Of The Marble And Limestone Monuments In The Urban Environment. Case Studies From Saint Petersburg, Russia, Olga V. Frank-Kamenetskaya, Dmitrii Yu Vlasov, Marina S. Zelenskaya, Irina V. Knauf, Maryia A. Timasheva Sep 2009

Decaying Of The Marble And Limestone Monuments In The Urban Environment. Case Studies From Saint Petersburg, Russia, Olga V. Frank-Kamenetskaya, Dmitrii Yu Vlasov, Marina S. Zelenskaya, Irina V. Knauf, Maryia A. Timasheva

Studia UBB Geologia

The results of a long-lasting research of sulphation process, which causes an essential deterioration of marble and limestone monuments in Saint Petersburg are reported. Based on a variety of field and analytical methods we can show that the decay process forming a gypsum-rich patina depends mainly on the local environment, the moisture accumulation, and is connected with the fissuring and porosity of the rock and the relief of a monument. Three main stages of gypsum-rich patina formation in the presence of microorganisms were revealed.


Deterioration Of Carbonate Rocks Used For Archeological Monuments In Tauric Chersonesos (Crimea), Alexander V. Mosyagin, Irina V. Knauf, Marina S. Zelenskaya Sep 2009

Deterioration Of Carbonate Rocks Used For Archeological Monuments In Tauric Chersonesos (Crimea), Alexander V. Mosyagin, Irina V. Knauf, Marina S. Zelenskaya

Studia UBB Geologia

The paper presents the mineralogy and petrography of the Proconesian marble and Chersonesian limestone, used as building materials from Antiquity to the medieval times in the Tauric Chersonesos, Crimea. The deterioration process, due to the modern time’s pollution and the climatic factors, is represented by forming of mainly gypsum-rich patina. The ubiquitous presence of micromycetes favors the stone decay.


Assessment Of Geohazards And Management Of Their Possible Impacts In The Kurbini Region, Albania, Arjan Beqiraj, Fran Gjoka, Mentor Lamaj, Majlinda Cenameri Sep 2009

Assessment Of Geohazards And Management Of Their Possible Impacts In The Kurbini Region, Albania, Arjan Beqiraj, Fran Gjoka, Mentor Lamaj, Majlinda Cenameri

Studia UBB Geologia

The small region of Kurbini, situated in the north western part of Albania, faces various hazards, due to the particular geographical position marked by the close neighbourhood of the high mountains and the Adriatic Sea. The hydrological and hydrogeological hazards, the deterioration of the groundwater quality, the intense erosion of the soil, the local acidification/contamination/salinization of the soil, and the desertification of land, are the most important geohazards threatening the area. A complex monitoring of all identified risk factors is necessary in order to avoid catastrophic events and irreversible damages.


Contrasting Recipes For The Kiln Furnitures Of The Faience Manufacture Granges-Le-Bourg (Haute Saône, France), Marino Maggetti, Denis Morin, Vincent Serneels, Christoph Neururer Sep 2009

Contrasting Recipes For The Kiln Furnitures Of The Faience Manufacture Granges-Le-Bourg (Haute Saône, France), Marino Maggetti, Denis Morin, Vincent Serneels, Christoph Neururer

Studia UBB Geologia

Thirty-nine samples of kiln furniture or technical ceramic (firing plate, saggars, spacers, props, wads) and six samples of building ceramics (bricks, tiles) from the manufacture of Granges-le-Bourg were studied by optical microscopy, X-ray fluorescence, X-ray diffraction and scanning electron microscopy. The kiln furniture is chemically inhomogeneous and belong to a CaO- + MgO-poor (firing plate, saggars) or a CaO- + MgO-rich (props, spacers, wads) group. Bricks and tiles pertain to the first group which was manufactured using decarbonatized top layers of local Triassic dolomitic marls. For the second group, the deeper layers were used. Plate and saggars are covered with …


Factors Influencing Perennial Pasture Adoption In The Medium Rainfall Zone Of The South West Natural Resource Management Region Of Western Australia, Ned Crossley, Stephen Tunbridge, Kathi Mcdonald Sep 2009

Factors Influencing Perennial Pasture Adoption In The Medium Rainfall Zone Of The South West Natural Resource Management Region Of Western Australia, Ned Crossley, Stephen Tunbridge, Kathi Mcdonald

Resource management technical reports

No abstract provided.


Improved Confidence In (U-Th)/He Thermochronology Using The Laser Microprobe: An Example From A Pleistocene Leucogranite, Nanga Parbat, Pakistan, J. W. Boyce, K. V. Hodges, D. King, James L. Crowley, M. Jercinovic, N. Chatterjee, S. A. Bowring, M. Searle Sep 2009

Improved Confidence In (U-Th)/He Thermochronology Using The Laser Microprobe: An Example From A Pleistocene Leucogranite, Nanga Parbat, Pakistan, J. W. Boyce, K. V. Hodges, D. King, James L. Crowley, M. Jercinovic, N. Chatterjee, S. A. Bowring, M. Searle

Geosciences Faculty Publications and Presentations

The newly developed laser microprobe (U-Th)/He thermochronometer permits, for the first time, the ability to generate precise (U-Th)/He cooling ages for even very young (Ma) samples with a spatial resolution on the order of tens of micrometers. This makes it possible to test the reproducibility of independent (U-Th)/He age determinations within individual crystals, further increasing the reliability of the method. As an example, we apply it here to a Pleistocene granite from Nanga Parbat, Pakistan, where previous constraints on the thermal history are consistent with rapid exhumation and cooling. Twenty-one (U-Th)/He dates determined on two monazite crystals from a single …


Multiproxy Lake Sediment Records At The Northern And Southern Boundaries Of The Aspen Parkland Region Of Manitoba, Canada, Rebecca Teed, Charles Umbanhower, Philip Camill Sep 2009

Multiproxy Lake Sediment Records At The Northern And Southern Boundaries Of The Aspen Parkland Region Of Manitoba, Canada, Rebecca Teed, Charles Umbanhower, Philip Camill

Earth and Environmental Sciences Faculty Publications

Aspen parkland in central Canada may change substantially with increased warming and aridity as prairies replace forests, fire return intervals decrease and lake levels decline. We examined the relationships among vegetation, climate, fire and lake-ecosystem properties using lake sediment cores from the current northern and southern boundaries of the aspen parkland in southwestern Manitoba. We analyzed pollen, charcoal, sediment magnetics, biogenic silica, phosphorus, grain size and LOI, and dated the cores using 210Pb and 14C (AMS, calibrated). The Jones Lake record, from the southern edge of the parkland, began considerably earlier (~11 000 cal. BP) than the Mallard …


Correlations Between Microbial Indicators, Pathogens, And Environmental Factors In A Subtropical Estuary, Cristina Ortega, Helena M. Solo-Gabriele, Amir Abdelzaher, Mary Wright, Yang Deng, Lillian M. Stark Sep 2009

Correlations Between Microbial Indicators, Pathogens, And Environmental Factors In A Subtropical Estuary, Cristina Ortega, Helena M. Solo-Gabriele, Amir Abdelzaher, Mary Wright, Yang Deng, Lillian M. Stark

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The objective of this study was to evaluate whether indicator microbes and physical-chemical parameters were correlated with pathogens within a tidally influenced Estuary. Measurements included the analysis of physical-chemical parameters (pH, salinity, temperature, and turbidity), measurements of bacterial indicators (enterococci, fecal coliform, Escherichia coli, and total coliform), viral indicators (somatic and MS2 coliphage), viral pathogens (enterovirus by culture), and protozoan pathogens (Cryptosporidium and Giardia). All pathogen results were negative with the exception of one sample which tested positive for culturable reovirus (8.5 MPN/100 L). Notable physical-chemical parameters for this sample included low salinity (< 1 ppt) and high water temperature (31 °C). Indicator bacteria and indicator virus levels for this sample were within average values typically measured within the study site and were low in comparison with levels observed in other freshwater environments. Overall results suggest that high levels of bacterial and viral indicators were associated with low salinity sites.


Understanding Paleoclimate And Human Evolution Through The Hominin Sites And Paleolakes Drilling Project, Andrew Cohen, Ramon Arrowsmith, Anna K. Behrensmeyer, Christopher Campisano, Craig Feibel, Shimeles Fisseha, Roy Johnson, Zelalem Bedaso, Charles Lockwood, Emma Mbua, Daniel Olago, Richard Potts, Kaye Reed, Robin Renaut, Jean-Jacques Tiercelin, Mohammed Umer Sep 2009

Understanding Paleoclimate And Human Evolution Through The Hominin Sites And Paleolakes Drilling Project, Andrew Cohen, Ramon Arrowsmith, Anna K. Behrensmeyer, Christopher Campisano, Craig Feibel, Shimeles Fisseha, Roy Johnson, Zelalem Bedaso, Charles Lockwood, Emma Mbua, Daniel Olago, Richard Potts, Kaye Reed, Robin Renaut, Jean-Jacques Tiercelin, Mohammed Umer

Department of Earth, Environment and Sustainability Faculty Publications

Understanding the evolution of humans and our close relatives is one of the enduring scientific issues of modern times. Since the time of Charles Darwin, scientists have speculated on how and when we evolved and what conditions drove this evolutionary story. The detective work required to address these questions is necessarily interdisciplinary, involving research in anthropology, archaeology, human genetics and genomics, and the earth sciences. In addition to the difficult tasks of finding, describing, and interpreting hominin fossils (the taxonomic tribe which includes Homo sapiens and our close fossil relatives from the last 6 Ma), much of modern geological research …


Quality Control Of Soil Water Data In Applied Climate, Jinshing You, Kenneth Hubbard, Rezaul Mamood, Venkataramana Sridhar, Dennis Todey Aug 2009

Quality Control Of Soil Water Data In Applied Climate, Jinshing You, Kenneth Hubbard, Rezaul Mamood, Venkataramana Sridhar, Dennis Todey

School of Natural Resources: Faculty Publications

Abstract: Soil moisture is a key state variable from both climate and hydrologic cycle assessment perspectives. Recently, automated measurements of soil moisture with sensors deployed at sites in a real-time monitoring network have provided valuable new data to monitor the soil water resource. However, to assure the quality of the data, quality control QC tools are needed. Earlier studies left little literature on the QC of soil water data as measurements were generally not part of a network that routinely collected measurements. This paper presents a systematic QC analysis and methodology to evaluate the performance of candidate QC techniques using …


A Phylogenetic Analysis Of Species Relationships In Hemlocks, The Genus Tsuga (Pinaceae)., Jordan David Baker Aug 2009

A Phylogenetic Analysis Of Species Relationships In Hemlocks, The Genus Tsuga (Pinaceae)., Jordan David Baker

Electronic Theses and Dissertations

The genus Tsuga is comprised of eight extant species found in North America and East Asia and four species represented by fossils from Europe and Japan. This study presents the first phylogenetic analysis based on structural, biochemical, and molecular sequence data. Characters obtained from published and unpublished literature were combined with new morphological characters from seeds, seedlings, and leaf cuticle material. Results from parsimony analyses of these characters differed from the published molecular based phylogeny. The non-molecular based phylogeny resolves two separate clades, a North American and an Asian, but did not group the western North American species, as in …


Root Production And Methane Dynamics: Impact Of Wetland Functional Group Diversity And Composition, Rachel Schultz, Virginie Bouchard, Serita D. Frey Aug 2009

Root Production And Methane Dynamics: Impact Of Wetland Functional Group Diversity And Composition, Rachel Schultz, Virginie Bouchard, Serita D. Frey

Faculty Publications

Background/Question/Methods: The loss of biodiversity worldwide has prompted a close investigation of the link between diversity and ecosystem functions. Most experimental studies have looked at the relationship between grassland plant diversity and aboveground productivity. Less is known about other ecosystems or how diversity affects belowground processes. Our objective was to investigate the link between plant community (diversity and composition) and key belowground processes such as root biomass production and CH4 dynamics in wetland ecosystems. We hypothesized that 1) root biomass would increase with functional group diversity due to complementarity and 2) the sediment pool of CH4 would decrease with diversity …


Proposed Enhanced Geothermal System Demonstration At The Nevada Test Site, Michael Voegele Aug 2009

Proposed Enhanced Geothermal System Demonstration At The Nevada Test Site, Michael Voegele

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.


Geometry Of The Trachyte Mesa Intrusion, Henry Mountains, Utah: Implications For The Emplacement Of Small Melt Volumes Into The Upper Crust, Paul H. Wetmore, Charles B. Connor, Sarah E. Kruse, Sean Callihan, Geoffrey Pignotta, Ciprian Stremtan, Andrea Burke Aug 2009

Geometry Of The Trachyte Mesa Intrusion, Henry Mountains, Utah: Implications For The Emplacement Of Small Melt Volumes Into The Upper Crust, Paul H. Wetmore, Charles B. Connor, Sarah E. Kruse, Sean Callihan, Geoffrey Pignotta, Ciprian Stremtan, Andrea Burke

Geology Faculty Publications

The Trachyte Mesa intrusion is one of several small satellite bodies to the larger intrusions of the Henry Mountains, Utah. Most previous studies have worked under the assumptions that Trachyte Mesa is blister shaped and intruded into flat and gently NW dipping strata. In this study we combine structural and geophysical data sets to constrain the structural geology of the host lithologies and the unmodified geometry of the intrusion. Trachyte Mesa intrudes a series of northeast trending upright and open folds formed within the Jurassic Entrada Formation. Truncation of these folds at the contact with the overlying Curtis/Summerville formations indicates …


Revised Crustal Architecture Of The Southeastern Carpathian Foreland From Active And Passive Seismic Data, Dana M. Enciu, Camelia C. Knapp, James H. Knapp Aug 2009

Revised Crustal Architecture Of The Southeastern Carpathian Foreland From Active And Passive Seismic Data, Dana M. Enciu, Camelia C. Knapp, James H. Knapp

Faculty Publications

Integration of active and passive source seismic data is employed in order to study the nature of the relationships between crustal seismicity and geologic structures in the southeastern (SE) Carpathian foreland of Romania and the possible connection with the Vrancea Seismogenic Zone (VSZ) of intermediatedepth seismicity, one of the most active earthquakeprone areas in Europe. Crustal epicenters and focal mechanisms are correlated with four deep industry seismic profiles, the reprocessed Danube and Carpathian Integrated Action on Process in the Lithosphere and Neotectonics (DACIA PLAN) profile and the Deep Reflection Acquisition Constraining Unusual Lithospheric Activity II and III (DRACULA) profiles in …


Researching Nitrite Oxidation At High Temperatures, Dolores A. Huang, Jeremy A. Dodsworth, Brian P. Hedlund Aug 2009

Researching Nitrite Oxidation At High Temperatures, Dolores A. Huang, Jeremy A. Dodsworth, Brian P. Hedlund

Undergraduate Research Opportunities Program (UROP)

15N-nitrate (NO3 -) pool dilution experiments show that ammonia (NH3) is oxidized to nitrate in geothermal springs up to at least 85C; however, nitrite (NO2 -)- oxidizing microorganisms are only known to grow up to 66°C. We hypothesize that thermophilic microorganisms oxidize nitrite to nitrate at high temperatures. Alternatively, it is possible that nitrite is oxidized abiotically. We propose to test these hypotheses by setting up microbial enrichments designed to grow thermophilic nitrite oxidizing bacteria by varying incubation temperature (50, 65, 80°C), oxygen concentration (20% and 5%), and cultivation media. A negative control consisting of filtered spring water (0.1 μm) …


Martian Life Detection With Xylose Enantiomers, Arturo White, Gaosun Zhang, Henry J. Sun Aug 2009

Martian Life Detection With Xylose Enantiomers, Arturo White, Gaosun Zhang, Henry J. Sun

Undergraduate Research Opportunities Program (UROP)

Ability of Martian soil to degrade carbohydrates, shown by the Viking mission, has two interpretations. One possibility is that the soil harbors living microorganisms. Alternatively, the soil is sterile but chemically oxidizing, i.e. it is laden with photochemical oxidants. It was shown by REU research last summer that these two possibilities can be distinguished by the use of glucose enantiomers. Life is selective: Earth organisms use D-glucose, but ignore Lglucose. This stereo selectivity is absent in chemical reactions. The goal of this project is to test if xylose, a five carbon sugar, is also suitable for chiral life detection. Mixed …


Martian Life Detection With Amino Acid Enantiomers, Ali Jamil, Gaosen Zhang, Henry J. Sun Aug 2009

Martian Life Detection With Amino Acid Enantiomers, Ali Jamil, Gaosen Zhang, Henry J. Sun

Undergraduate Research Opportunities Program (UROP)

The Viking mission showed that Martian soil can degrade a heterotrophic medium to carbon dioxide as if live microorganisms were present. The result is considered inconclusive, however, because abiotic oxidants, such as superoxides, may also exist on Mars and would explain the Viking result. One way to resolve this ambiguity is to repeat the Viking experiment with a isomerically pure medium. The consumption of one isomer, either D or L, would indicate biological activity. Indiscriminate destruction of both isomers would indicate abiotic redox processes. This idea was validated for glucose by REU research last summer (Sun et al. 2009). The …


Temperature Links To Compositional Variations At Mutnovsky Volcano, Kamchatka, Russia, Lindsey Clark, Adam Simon, Kelly L. Robertson, Sean Mulcahy Aug 2009

Temperature Links To Compositional Variations At Mutnovsky Volcano, Kamchatka, Russia, Lindsey Clark, Adam Simon, Kelly L. Robertson, Sean Mulcahy

Undergraduate Research Opportunities Program (UROP)

Full petrographic descriptions of fifty two rock samples collected from one hundred thousand year old Mutnovsky Volcano, Kamchatka, Russia are being studied to determine the magma compositions of the volcano through time. I expect that the composition will change with time owing to variation in input at the base of the volcano pluming system, above the subducting Pacific Ocean crust. This variation in composition, including the abundance of important atmospheric gases, water, and carbon dioxide, may play a key role in the abundance and type of greenhouse gases being emitted. The samples will also be analyzed by using electron probe …


Obtaining Parsimonious Hydraulic Conductivity Fields Using Head And Transport Observations: A Bayesian Geostatistical Parameter Estimation Approach, Michael Fienen, R. Hunt, D. Krabbenhoft, Tom Clemo Aug 2009

Obtaining Parsimonious Hydraulic Conductivity Fields Using Head And Transport Observations: A Bayesian Geostatistical Parameter Estimation Approach, Michael Fienen, R. Hunt, D. Krabbenhoft, Tom Clemo

CGISS Publications and Presentations

Flow path delineation is a valuable tool for interpreting the subsurface hydrogeochemical environment. Different types of data, such as groundwater flow and transport, inform different aspects of hydrogeologic parameter values (hydraulic conductivity in this case) which, in turn, determine flow paths. This work combines flow and transport information to estimate a unified set of hydrogeologic parameters using the Bayesian geostatistical inverse approach. Parameter flexibility is allowed by using a highly parameterized approach with the level of complexity informed by the data. Despite the effort to adhere to the ideal of minimal a priori structure imposed on the problem, extreme contrasts …


Complex Dielectric Permittivity Measurements From Ground-Penetrating Radar Data To Estimate Snow Liquid Water Content In The Pendular Regime, John H. Bradford, Joel T. Harper, Joel Brown Aug 2009

Complex Dielectric Permittivity Measurements From Ground-Penetrating Radar Data To Estimate Snow Liquid Water Content In The Pendular Regime, John H. Bradford, Joel T. Harper, Joel Brown

CGISS Publications and Presentations

Monitoring the snow water equivalent (SWE) is critical to effective management of water resources in many parts of the world that depend on the mountain snowpack for water storage. There are currently no methods to remotely sense SWE with accuracy over large lateral distances in the steep and often forested terrain of mountain basins. Previous studies have shown that measurements of ground-penetrating radar (GPR) velocity can provide accurate estimates of SWE in dry snow. Introduction of liquid water into the snowpack results in a three-phase system that cannot be accurately characterized with GPR velocity alone. We show that measuring the …


Complex Dielectric Permittivity Measurements From Ground-Penetrating Radar Data To Estimate Snow Liquid Water Content In The Pendular Regime, John H. Bradford, Joel T. Harper, Joel Brown Aug 2009

Complex Dielectric Permittivity Measurements From Ground-Penetrating Radar Data To Estimate Snow Liquid Water Content In The Pendular Regime, John H. Bradford, Joel T. Harper, Joel Brown

Geosciences Faculty Publications

Monitoring the snow water equivalent (SWE) is critical to effective management of water resources in many parts of the world that depend on the mountain snowpack for water storage. There are currently no methods to remotely sense SWE with accuracy over large lateral distances in the steep and often forested terrain of mountain basins. Previous studies have shown that measurements of ground-penetrating radar (GPR) velocity can provide accurate estimates of SWE in dry snow. Introduction of liquid water into the snowpack results in a three-phase system that cannot be accurately characterized with GPR velocity alone. We show that measuring the …