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- Depositional fluxes of 7Be and 210Pb (5)
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- Deposition velocity (3)
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Articles 31 - 60 of 73
Full-Text Articles in Geology
Temporal Variations Of Atmospheric Depositional Fluxes Of 7be And 210pb Over 8 Years (2006–2013) At Shanghai, China, And Synthesis Of Global Fallout Data, Juan Du, Jinzhou Du, Mark Baskaran, Qianqian Bi, Dekun Huang, Yifei Jiang
Temporal Variations Of Atmospheric Depositional Fluxes Of 7be And 210pb Over 8 Years (2006–2013) At Shanghai, China, And Synthesis Of Global Fallout Data, Juan Du, Jinzhou Du, Mark Baskaran, Qianqian Bi, Dekun Huang, Yifei Jiang
Environmental Science and Geology Faculty Research Publications
7Be and 210Pb, two atmospherically delivered radionuclides, have been broadly applied to study the processes including air mass transport, soil erosion, and particle cycling in aqueous systems. These studies require temporal variations of their depositional fluxes. In the present work, monthly atmospheric bulk depositional fluxes of 7Be and 210Pb were measured over 8 years (December 2005 to December 2013) at Shanghai, China. The bulk depositional fluxes of 7Be and 210Pb varied from 17.9 to 421 Bq m−2 month−1 and 6.8 to 82.1 Bq m−2 month−1, respectively. The volume‐weighted activities ranged from 0.20 to 8.06 Bq L−1 for 7Be and 0.05 …
Effects Of Anthropogenic Particles On The Chemical And Geophysical Properties Of Urban Soils, Detroit, Michigan, Katharine Orlicki
Effects Of Anthropogenic Particles On The Chemical And Geophysical Properties Of Urban Soils, Detroit, Michigan, Katharine Orlicki
Wayne State University Theses
There is a great need in many cities for a better quality of urban soil maps. This is due to the increasing interest in repurposing vacant land for urban redevelopment, agriculture, and green infrastructure. Mapping vacant urban land in Detroit can be very difficult because anthropogenic soils were often highly variable and frequently contained demolition debris (such as brick), this makes it difficult to use a hand auger. This study was undertaken in Detroit, MI to create a more efficient way to map urban soils based on their geophysical and chemical properties. This will make the mapping process faster, less …
Inference Of Hydrogeological Conditions And Source History Of Groundwater Contaminants Using 3-D Modeling And Human Health Risk Assessment, Mary Rosanna Carnagie
Inference Of Hydrogeological Conditions And Source History Of Groundwater Contaminants Using 3-D Modeling And Human Health Risk Assessment, Mary Rosanna Carnagie
Wayne State University Theses
This study was completed using data interpolation and human health risk modules in Spatial Analysis and Decision Assistance (SADA) software to model a 3-D time-series of 1,4-dioxane and vinyl chloride plumes and their associated health risks to infer hydrogeological conditions at the Ann Arbor Landfill site. Ordinary kriging estimates of contaminant distribution and human health risk distribution provide insight to groundwater flow direction, hydraulic conductivity distribution, and source history of contaminants at sites with groundwater contamination in a glacial aquifer system. More studies with larger datasets in glacial aquifer systems are necessary to prove these correlations, but this thesis illustrates …
Impacts Of Anthropogenic Watershed Activity On The Sedimentary Record Of Dams From The Midwestern United States: A Case Study From Michigan And Indiana, Jenna Hage-Hassan
Impacts Of Anthropogenic Watershed Activity On The Sedimentary Record Of Dams From The Midwestern United States: A Case Study From Michigan And Indiana, Jenna Hage-Hassan
Wayne State University Theses
Large-scale watershed land use changes, including urbanization, have resulted in accelerated soil erosion and sediment accumulation rates, which in turn have posed a threat to the longevity and productivity of a majority of the aging dams in the mid-western United States. In this study, we collected and analyzed 3 sediment cores each from two dams from the Mid-western United States: Webber Dam in Michigan and Goshen Pond Dam in Indiana. Cores were analyzed for 137Cs and 210Pb to establish chronology, as well as concentrations and isotopic composition of organic carbon and nitrogen to investigate the land use changes as preserved …
Evaluation Of Hygroscopic Soil Amendments And Natural Freeze-Thaw Cycling To Accelerate The Mechanical Breakdown Of Artifacts In Demolition Site Soils, Phillip Joseph Backers
Evaluation Of Hygroscopic Soil Amendments And Natural Freeze-Thaw Cycling To Accelerate The Mechanical Breakdown Of Artifacts In Demolition Site Soils, Phillip Joseph Backers
Wayne State University Theses
Many cities worldwide have areas of vacant land produced by building demolition. This open space has attracted great interest as a potential resource for green infrastructure, urban agriculture, and other purposes related to urban renewal. Unfortunately, rock-like artifacts (e.g. brick, mortar, concrete) are often present in great abundance in demolition site soils. These artifacts make the soil difficult to till, create obstacles for root penetration, and limit the soil’s water-holding capacity, infiltration and aeration. As an alternative to physical removal, this study was carried out to test the feasibility of using hygroscopic compounds as soil amendments to accelerate the mechanical …
Analysis, Toxicity, Occurrence And Biodegradation Of Nonylphenol Isomers: A Review, Zhijiang Lu, Jay Gan
Analysis, Toxicity, Occurrence And Biodegradation Of Nonylphenol Isomers: A Review, Zhijiang Lu, Jay Gan
Environmental Science and Geology Faculty Research Publications
Over the last two decades, nonylphenols (NPs) have become to be known as a priority hazardous substance due primarily to its estrogenicity and ubiquitous occurrence in the environment. Nonylphenols are commonly treated as a single compound in the evaluation of their environmental occurrence, fate and transport, treatment or toxicity. However, technical nonylphenols (tNPs) are in fact a mixture of more than 100 isomers and congeners. Recent studies showed that some of these isomers behaved significantly differently in occurrence, estrogenicity and biodegradability. The most estrogenic isomer was about 2 to 4 times more active than tNP. Moreover, the half lives of …
Influence Of Introgression And Geological Processes On Phylogenetic Relationships Of Western North American Mountain Suckers (Pantosteus, Catostomidae), Peter J. Unmack, Thomas E. Dowling, Nina J. Laitinen, Carol L. Secor, Richard L. Mayden, Dennis K. Shiozawa, Gerald R. Smith
Influence Of Introgression And Geological Processes On Phylogenetic Relationships Of Western North American Mountain Suckers (Pantosteus, Catostomidae), Peter J. Unmack, Thomas E. Dowling, Nina J. Laitinen, Carol L. Secor, Richard L. Mayden, Dennis K. Shiozawa, Gerald R. Smith
Biological Sciences Faculty Research Publications
Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus is one of several clades centered in this tectonically active region. The eight recognized Pantosteus species are widespread and common across southwestern Canada, western USA and into northern Mexico. They are typically found in medium gradient, middle-elevation reaches of rivers over rocky substrates. This study (1) compares molecular data …
The Role Of Conservation Partnerships Between Scientists And Nonprofit Agencies In Freshwater Science And Management, Robert S. Stelzer, Donna R. Kashian
The Role Of Conservation Partnerships Between Scientists And Nonprofit Agencies In Freshwater Science And Management, Robert S. Stelzer, Donna R. Kashian
Environmental Science and Geology Faculty Research Publications
Funding agencies and scientific researchers are finding increasingly often that partnerships with nonprofit organizations and local communities are necessary to obtain sustainable outcomes. Scientists, nonprofit organizations, community members, and managers can extract ideas from these examples to guide development of successful new partnerships. Professional scientists and the community at large, including non-profit organizations, benefit from increased engagement and power sharing.
Capacity Building In Stakeholders Around Detroit Riverfish Consumption Advisory Issues, Donna R. Kashian, Ann E. Krause, Larissa Sano, Branda Nowell, Ken G. Drouillard
Capacity Building In Stakeholders Around Detroit Riverfish Consumption Advisory Issues, Donna R. Kashian, Ann E. Krause, Larissa Sano, Branda Nowell, Ken G. Drouillard
Environmental Science and Geology Faculty Research Publications
The Detroit River is an international water body that has several fish consumption advisories for contaminants that affect human health and economic revenue for the USA and Canada. Despite the importance of these advisories, little progress has been made in developing effective management strategies or coordinating monitoring, research, and policy efforts between the 2 nations. We engaged 44 stakeholder organizations to in- crease community capacity on these issues for the Detroit River. We assessed capacity with key informant interviews and a network survey. Our analysis identified weak ties in information sharing and collaboration between countries. We used this information to …
Radon Loss From Zircon: Effects Of Microstructure On Radon Emanation And Diffusion, Marty Eakin
Radon Loss From Zircon: Effects Of Microstructure On Radon Emanation And Diffusion, Marty Eakin
Wayne State University Theses
Radon emanation from rocks and minerals is ubiquitous, but the mechanisms of radon loss are not well understood. Quantification of radon emanation rates from zircon has potential bearing on the reliability of U-Pb ages of zircon bearing rocks. The 238U decay chain includes 222Rn, a noble gas, which has a half-life of 3.82 days and can escape from the crystal structure of zircon if sufficient pathways exist, or by recoil if the parent 238U was very near the outer edge of the crystal. Loss of 222Rn ultimately leads to a deficiency of 206Pb, resulting in discordance between 238U-206Pb, 235U-207Pb, and …
Evaluating Spatial Outliers And Integrating Temporal Data In Air Pollution Models For The Detroit-Windsor Airshed, Brendan Francis O'Leary
Evaluating Spatial Outliers And Integrating Temporal Data In Air Pollution Models For The Detroit-Windsor Airshed, Brendan Francis O'Leary
Wayne State University Theses
The heterogeneous nature of urban air complicates human exposure estimates and creates a need for accurate, highly detailed spatiotemporal air contaminant models. The study expands on previous investigations by the Geospatial Determinants of Health Outcomes Consortium that examined relationships between air pollutant distributions and asthma exacerbations. Two approaches, the removal of spatial data outliers and the integration of spatial and temporal data, were used to refine air quality models in the Detroit and Windsor international airshed. The evaluation of associations between the resulting air quality models and asthma exacerbations in Detroit and Windsor revealed weaker correlations with spatial outliers removed …
Investigating The Anisotropy Of Magnetic Susceptibility And Other Rock Magnetic Properties Of The Beaver River Diabase In Northeastern Minnesota, Samer H. Hariri
Investigating The Anisotropy Of Magnetic Susceptibility And Other Rock Magnetic Properties Of The Beaver River Diabase In Northeastern Minnesota, Samer H. Hariri
Wayne State University Theses
The Beaver River Diabase (BRD) is a series of mafic dikes and sills within the Beaver Bay Complex (BBC) of northern Minnesota, which formed during the development of the ~1.1 Ga Midcontinent Rift (MCR). The BRD is one of the youngest and most extensive intrusive phases of the BBC. The BRD dikes and sills were emplaced into the medial levels of the 6-10 kilometer-thick North Shore Volcanic Group and occur over an arcuate area extending 120 by 20 kilometers. The BRD is composed of fine- to medium-grained ophitic olivine gabbro and does not display obvious foliation or lineation features and …
Reverse-Time Migration-Based Reflection Tomography Using Teleseismic Free Surface Multiples, S. Burdick, M. V. De Hoop, R. D. Van Der Hilst
Reverse-Time Migration-Based Reflection Tomography Using Teleseismic Free Surface Multiples, S. Burdick, M. V. De Hoop, R. D. Van Der Hilst
Environmental Science and Geology Faculty Research Publications
Converted and multiply reflected phases from teleseismic events are routinely used to create structural images of the crust–mantle boundary (Moho) and the elasticity contrasts within the crust and upper mantle. The accuracy of these images is to a large extent determined by the background velocity model used to propagate these phases to depth. In order to improve estimates of 3-D velocity variations and, hence, improve imaging, we develop a method of reverse-time migration-based reflection tomography for use with wavefields from teleseismic earthquakes recorded at broad-band seismograph arrays. Reflection tomography makes use of data redundancy—that is, the ability to generate numerous …
Scavenging, Cycling And Removal Fluxes Of 210Po And 210Pb At The Bermuda Time-Series Study Site, G. H. Hong, M. Baskaran, T. M. Church, M. Conte
Scavenging, Cycling And Removal Fluxes Of 210Po And 210Pb At The Bermuda Time-Series Study Site, G. H. Hong, M. Baskaran, T. M. Church, M. Conte
Environmental Science and Geology Faculty Research Publications
Quantifying relative affinities of Po and Pb in different populations of marine particulate matter is of great importance in utilizing 210Po as a tracer for carbon cycling. We collected and analyzed water samples for the concentrations of dissolved and total 210Po and 210Pb from the upper 600 m of the water column at Bermuda Time-series Study site (September 1999 to September 2000) to investigate their seasonality of concentrations and their ac-tivity ratio (210Po/210Pb activity ratio, AR). Sinking particles collected in sediment traps at depths of 500 m, 1500 m, and 3200 m from …
Microstructures And Quartz Lattice-Preferred Orientations In The Eclogite-Bearing Migmatitic Gneisses Of The D’Entrecasteaux Islands, Papua New Guinea, T. A. Little, B. R. Hacker, S. J. Brownlee, G. Seward
Microstructures And Quartz Lattice-Preferred Orientations In The Eclogite-Bearing Migmatitic Gneisses Of The D’Entrecasteaux Islands, Papua New Guinea, T. A. Little, B. R. Hacker, S. J. Brownlee, G. Seward
Environmental Science and Geology Faculty Research Publications
Lattice preferred orientations (LPO) of quartz in gneiss domes of the D’Entrecasteaux Islands, Woodlark Rift shed insight into exhumation of the world’s youngest (~5–7Ma) eclogite-bearing terrane at cm/yr rates. We focus on deformation that affected the terrane as it transited between lower crustal depths and the surface, including: (1) grain-scale deformation mechanisms; and (2) style of flow and mode of emplacement of the domes. Electron-backscatter diffraction was used to analyze microstructure and LPOs of 37 quartzofeldspathic gneiss samples that enclose meter-scale mafic blocks preserving original eclogite-facies assemblages. During exhumation of the ultrahigh-pressure (UHP) terrane, gneisses were retrogressed in the amphibolite …
A Combined Radio- And Stable-Isotopic Study Of A California Coastal Aquifer System, Peter W. Swarzenski, Mark Baskaran, Robert J. Rosenbauer, Brian D. Edwards, Michael Land
A Combined Radio- And Stable-Isotopic Study Of A California Coastal Aquifer System, Peter W. Swarzenski, Mark Baskaran, Robert J. Rosenbauer, Brian D. Edwards, Michael Land
Environmental Science and Geology Faculty Research Publications
Stable and radioactive tracers were utilized in concert to characterize geochemical processes in a complex coastal groundwater system and to provide constraints on the kinetics of rock/water interactions. Groundwater samples from wells within the Dominguez Gap region of Los Angeles County, California were analyzed for a suite of major cations (Na+, K+, Mg2+, Ca2+) and anions (Cl−, SO42−), silica, alkalinity, select trace elements (Ba, B, Sr), dissolved oxygen, stable isotopes of hydrogen (δD), oxygen (δ18O), dissolved inorganic carbon (δ13CDIC), and radioactive …
Effects Of Flow Rates And Composition Of The Filter, And Decay/Ingrowth Correction Factors Involved With The Determination Of In Situ Particulate 210Po And 210Pb In Seawater, Mark Baskaran, Thomas Church, Gi Hong, Anupam Kumar, Ma Qiang, Hui Choi, Sylvain Rigaud, Kanchan Maiti
Effects Of Flow Rates And Composition Of The Filter, And Decay/Ingrowth Correction Factors Involved With The Determination Of In Situ Particulate 210Po And 210Pb In Seawater, Mark Baskaran, Thomas Church, Gi Hong, Anupam Kumar, Ma Qiang, Hui Choi, Sylvain Rigaud, Kanchan Maiti
Environmental Science and Geology Faculty Research Publications
Accurate measurements of particulate 210Po (210Pop) and 210Pb (210Pbp) are required in the investigation of (i) partitioning of Po and Pb between particulate and dissolved phases and (ii) export estimates of carbon and other key trace metals from the euphotic zone via sinking particulate matter. Based on the intercomparison of different composition of the filter material (QMA, Supor, Millipore, and Pall GN6) and flow rates (2 to 8 L min), we show how these factors affect the measured concentrations of 210Pop and 210Pbp and their activity …
Lithogeochemical And Stable Isotope Characteristics Of Bristol And Northern Thorneloe Townships And Its Correlation With Gold Mineralization, Zachary Grant Stevison
Lithogeochemical And Stable Isotope Characteristics Of Bristol And Northern Thorneloe Townships And Its Correlation With Gold Mineralization, Zachary Grant Stevison
Wayne State University Theses
The Porcupine Mining Camp located in the southwestend of the Abitibi Greenstone Belt has been mined extensively for its prolific precious and base metal enrichment. This study targeted Bristol and Northern Thorneloe, fifteen kilometers southwest of Timmins, ON, an area that is of economic interest for its gold mineralization. Rock samples were collected (drill- core and outcrop) throughout both townships and analyzed for their major and trace element composition, These were used to determine hydrothermal alteration signatures as well as specific elemental enrichment that relate to gold mineralization in Bristol-Thorneloe Township. Quartz-carbonate and quartz-carbonate-tourmaline vein samples were also collected near …
Intercalibration Studies Of 210Po And 210Pb In Dissolved And Particulate Seawater Samples, Thomas Church, Sylvain Rigaud, Mark Baskaran, Anupam Kumar, Jana Friedrich, Pere Masque, Viena Puigcorbé, Guebuem Kim, Olivier Radakovitch, Gi Hong, Hui Choi, Gillian Stewart
Intercalibration Studies Of 210Po And 210Pb In Dissolved And Particulate Seawater Samples, Thomas Church, Sylvain Rigaud, Mark Baskaran, Anupam Kumar, Jana Friedrich, Pere Masque, Viena Puigcorbé, Guebuem Kim, Olivier Radakovitch, Gi Hong, Hui Choi, Gillian Stewart
Environmental Science and Geology Faculty Research Publications
Documented is an intercalibration (IC) exercise for both 210Po and 210Pb in seawater aliquots distributed between up to eight international laboratories that followed individual protocols. Dissolved and particulate samples were provided by GEOTRACES during two IC cruises at baseline stations in the North Atlantic and North Pacific oceans. Included were surface and/or deep dissolved and particulate samples at each site, plus complete profiles analyzed by the laboratory of the lead author. An unspecified solid phase standard was also distributed with 210Po and 210Pb in secular equilibrium to confirm spike calibrations. The 210Po activities reported n …
Depositional Fluxes And Concentrations Of 7Be And 210Pb In Bulk Precipitation And Aerosols At The Interface Of Atlantic And Mediterranean Coasts In Spain, R. L. Lozano, E. G. San Miguel, J. P. Bolívar, M. Baskaran
Depositional Fluxes And Concentrations Of 7Be And 210Pb In Bulk Precipitation And Aerosols At The Interface Of Atlantic And Mediterranean Coasts In Spain, R. L. Lozano, E. G. San Miguel, J. P. Bolívar, M. Baskaran
Environmental Science and Geology Faculty Research Publications
Bulk depositional fluxes of 7Be and 210Pb in precipitation measured over a period of 16 months (April 2009–July 2010) in Huelva, Spain varied between 5.6 and 186 Bq m−2 month−1 (annual mean: 834 Bq m−2 year−1) and 0.8 and 8.1 Bq m−2 month−1 (annual mean: 59 Bq m−2 year−1), respectively, with the lowest depositional fluxes occurring during dry summer months. Quantitative evaluation of the precipitation-normalized seasonal depositional fluxes of 7Be and 210Pb indicates that the enrichment factor in winter is < 1.0 while in 2010 spring, it is significantly higher than 1, possibly indicating input of air from the stratosphere-troposphere exchange (for 7Be). The specific activities of …
Magnetic Properties Of Ilmenite‐Hematite Single Crystals From The Ecstall Pluton Near Prince Rupert, British Columbia, Sarah J. Brownlee, Joshua M. Feinberg, Takeshi Kasama, Richard J. Harrison, Gary R. Scott, Paul R. Renne
Magnetic Properties Of Ilmenite‐Hematite Single Crystals From The Ecstall Pluton Near Prince Rupert, British Columbia, Sarah J. Brownlee, Joshua M. Feinberg, Takeshi Kasama, Richard J. Harrison, Gary R. Scott, Paul R. Renne
Environmental Science and Geology Faculty Research Publications
Paleomagnetic studies of the 91 Ma Ecstall pluton and other Cretaceous plutons of British Columbia imply large northward tectonic movements (>2000 km) may have occurred during the tectonic evolution of western North America. However, more recent studies have shown that the eastern edge of the Ecstall pluton experienced considerable mineralogical changes as younger Eocene plutons, such as the ∼58 Ma Quottoon Pluton, were emplaced along its margins. We investigated changes in the rock magnetic properties associated with this reheating event by examining isolated grains of intergrown ilmenite and hematite, the primary paleomagnetic recorder in the Ecstall pluton. Measurements of …
Predicted Velocity And Density Structure Of The Exhuming Papua New Guinea Ultrahigh‐Pressure Terrane, Sarah J. Brownlee, Bradley R. Hacker, Matthew Salisbury, Gareth Seward, Timothy A. Little, Suzanne A. Baldwin, Geoffrey A. Abers
Predicted Velocity And Density Structure Of The Exhuming Papua New Guinea Ultrahigh‐Pressure Terrane, Sarah J. Brownlee, Bradley R. Hacker, Matthew Salisbury, Gareth Seward, Timothy A. Little, Suzanne A. Baldwin, Geoffrey A. Abers
Environmental Science and Geology Faculty Research Publications
New electron backscatter diffraction measurements show that the Papua New Guinea (PNG) ultrahigh‐pressure (UHP) terrane is dominated by rocks with weakly oriented quartz and feldspar and less abundant strongly oriented hornblende, clinopyroxene, and mica. Velocities measured at high pressures (600 MPa) show that VP is 5.8–6.3 km/s for gneiss samples, 6.5–7.7 km/s for amphibolite, and 7.7–8.2 km/s for eclogite and VS is 3.4–3.9 km/s for gneiss, 4.0–4.4 km/s for amphibolite, and 4.5–4.6 km/s for eclogite. Velocities and anisotropies calculated from mineral crystal preferred orientations (CPOs) are equivalent to within 5% of the measured values. The highest seismic anisotropy …
Reproduction And Genetic Detection Of Veligers In Changing Dreissena Populations In The Great Lakes, Jeffrey L. Ram, Aos S. Karim, Payel Acharya, Pranav Jagtap, Sonal Purohit, Donna R. Kashian
Reproduction And Genetic Detection Of Veligers In Changing Dreissena Populations In The Great Lakes, Jeffrey L. Ram, Aos S. Karim, Payel Acharya, Pranav Jagtap, Sonal Purohit, Donna R. Kashian
Environmental Science and Geology Faculty Research Publications
Dreissenid bivalves, Dreissena polymorpha (zebra mussel) and Dreissena bugensis (quagga mussel) are biofouling species that invaded the Great Lakes region of North America from source populations in Europe in the 1980s. Initially, D. polymorpha spread faster and farther; however, D. bugensis have recently displaced D. polymorpha in many areas of the Great Lakes and was the first to be found west of the Continental Divide. Early detection of dreissenids is important in anticipating and preventing potentially high economic impacts. To study population dynamics and to enhance detection methods, we assessed “spawnability” using a serotonin bioassay and developed a new, sensitive, …
Thermal History Of The Ecstall Pluton From 40Ar/39Ar Geochronology And Thermal Modeling, Sarah J. Brownlee, Paul R. Renne
Thermal History Of The Ecstall Pluton From 40Ar/39Ar Geochronology And Thermal Modeling, Sarah J. Brownlee, Paul R. Renne
Environmental Science and Geology Faculty Research Publications
New 40Ar/39Ar thermochronology results and thermal modeling support the hypothesis of Hollister et al. (2004), that reheating of the mid-Cretaceous Ecstall pluton by intrusion of the Coast Mountains Batholith (CMB) was responsible for spatially variable remagnetization of the Ecstall pluton. 40Ar/39Ar ages from hornblende and biotite from 12 locations along the Skeena River across the northern part of the Ecstall pluton decrease with proximity to the Quottoon plutonic complex, the nearest member of the CMB to the Ecstall pluton. The oldest 40Ar/39Ar ages are found farthest from the Quottoon plutonic …
What Are The Causes, Consequences And Correctives Of Fish Contamination In The Detroit River Aoc That Cause Health Consumption Advisories? (Final Report, Michigan Sea Grant Michu-T-10-001), Donna R. Kashian, Ken G. Drouillard, D. Haffner, Ann E. Krause, Z Liu, Larissa Sano
What Are The Causes, Consequences And Correctives Of Fish Contamination In The Detroit River Aoc That Cause Health Consumption Advisories? (Final Report, Michigan Sea Grant Michu-T-10-001), Donna R. Kashian, Ken G. Drouillard, D. Haffner, Ann E. Krause, Z Liu, Larissa Sano
Environmental Science and Geology Faculty Research Publications
Using an Integrated Assessment (IA) framework, we consolidated and utilized existing data from the Detroit River to develop models that both identify possible drivers of elevated fish contaminant body burdens, and to facilitate a more risk-based approach of tissue trigger-levels for consumption advisories. This integrated assessment approach was particularly useful for consumption advisories as it provided the ability to integrate and organize complex data in a manner that can help inform management decisions. In addition, the IA framework explicitly fosters collaboration and participation of multiple interested groups. We have capitalized on this component of IAs, by seeking the active participation …
Constraints On The Utility Of Mno2 Cartridge Method For The Extraction Of Radionuclides: A Case Study Using 234Th, M. Baskaran, P. W. Swarzenski, B. A. Biddanda
Constraints On The Utility Of Mno2 Cartridge Method For The Extraction Of Radionuclides: A Case Study Using 234Th, M. Baskaran, P. W. Swarzenski, B. A. Biddanda
Environmental Science and Geology Faculty Research Publications
Large volume (102–103 L) seawater samples are routinely processed to investigate the partitioning of particle reactive radionuclides and Ra between solution and size-fractionated suspended particulate matter. One of the most frequently used methods to preconcentrate these nuclides from such large volumes involves extraction onto three filter cartridges (a prefilter for particulate species and two MnO2-coated filters for dissolved species) connected in series. This method assumes that the extraction efficiency is uniform for both MnO2-coated cartridges, that no dissolved species are removed by the prefilter, and that any adsorbed radionuclides are not desorbed from …
A New Global Model For P Wave Speed Variations In Earth's Mantle, Chang Li, Robert D. Van Der Hilst, E. Robert Engdahl, Scott Burdick
A New Global Model For P Wave Speed Variations In Earth's Mantle, Chang Li, Robert D. Van Der Hilst, E. Robert Engdahl, Scott Burdick
Environmental Science and Geology Faculty Research Publications
We document our tomographic method and present a new global model of three-dimensional (3-D) variations in mantle P wave velocity. The model is parameterized by means of rectangular cells in latitude, longitude, and radius, the size of which adapts to sampling density by short-period (1 Hz) data. The largest single data source is ISC/NEIC data reprocessed by Engdahl and coworkers, from which we use routinely picked, short-period P, Pg, Pn, pP, and pwP data (for earthquakes during the period 1964∼2007). To improve the resolution in the lowermost and uppermost mantle, we use differential times of core phases (PKPAB − PKPDF, …
The Influence Of Metal Exposure History And Ultraviolet-B Radiation On Benthic Communities In Colorado Rocky Mountain Streams, Robert E. Zuellig, Donna R. Kashian, Marjorie L. Brooks, Peter M. Kiffney, William H. Clements
The Influence Of Metal Exposure History And Ultraviolet-B Radiation On Benthic Communities In Colorado Rocky Mountain Streams, Robert E. Zuellig, Donna R. Kashian, Marjorie L. Brooks, Peter M. Kiffney, William H. Clements
Environmental Science and Geology Faculty Research Publications
Interest in understanding the influence of ultraviolet-B (UVB; 280–320 nm) radiation in aquatic ecosystems has increased since the early 1990s. Pollution from historic mining operations coupled with physicochemical characteristics of Rocky Mountain streams that increase exposure of benthic communities to UVB provided an opportunity to examine how UVB interacted with heavy metal contamination to structure stream communities. We integrated a series of UVB addition experiments done in stream microcosms with a large-scale UVB shading experiment to test the hypothesis that effects of UVB were greater on benthic communities from metal-polluted streams than from reference streams. Microcosm experiments involved short-term exposure …
Residence Times And Temporal Variations Of 210Po In Aerosols And Precipitation From Southeastern Michigan, United States, Daphne Mcneary, Mark Baskaran
Residence Times And Temporal Variations Of 210Po In Aerosols And Precipitation From Southeastern Michigan, United States, Daphne Mcneary, Mark Baskaran
Environmental Science and Geology Faculty Research Publications
Daughter products of 222Rn (such as 210Pb, half-life = 22.1 years, and 210Po, half-life = 138 days) have been widely used as tracers to determine the removal rates of aerosols as well to obtain analog information on the behavior of other chemical species in the lower atmosphere. To establish the first data set on the depositional fluxes of 210Po in bulk precipitation and concentrations in air samples from the midwestern United States, we measured the depositional fluxes of 210Pb and 210Po in the bulk (wet plus dry) and dry fallout by deploying a rain …
The Quartzite Problem Revisited, Jeffrey L. Howard
The Quartzite Problem Revisited, Jeffrey L. Howard
Environmental Science and Geology Faculty Research Publications
A review of past terminology and previous petrological studies suggests that quartzite should be classified descriptively as both a sedimentary and a metamorphic rock. Quartzite is identified in the field as a quartz‐rich rock (exclusive of chert and vein quartz) that is exceptionally hard and, when broken by a rock hammer, fractures irregularly through both grains and cement (where present) to form an irregular or conchoidal fracture surface. Quartzite is differentiated from quartzose sandstone (arenite), which is softer and fractures around individual grains, and from chert and vein quartz by a bright vitreous luster. Quartzite is classified further on the …