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2012

Geology

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Full-Text Articles in Physical Sciences and Mathematics

Using Marine Snails To Teach Biogeography And Macroevolution: The Role Of Larvae And Dispersal Ability In The Evolution And Persistence Of Species, Jonathan R. Hendricks Dec 2012

Using Marine Snails To Teach Biogeography And Macroevolution: The Role Of Larvae And Dispersal Ability In The Evolution And Persistence Of Species, Jonathan R. Hendricks

Faculty Publications

While some marine animals are capable of traveling great distances, many have limited mobility as adults and spend the majority of their lifetimes in a small geographical area or may even be cemented to a single place. While it might be expected that species with limited mobility would have small geographic distributions, some nevertheless occur over very large areas. This is the case for some marine snails (gastropods). A key factor that impacts the geographic distribution of marine snails is the type of larvae they have during the phase of their life history that follows hatching from an egg. Because …


Autumn Migration Of Mississippi Flyway Mallards As Determined By Satellite Telemetry, David George G. Krementz, Kwasi Asante, Luke W. Naylor Dec 2012

Autumn Migration Of Mississippi Flyway Mallards As Determined By Satellite Telemetry, David George G. Krementz, Kwasi Asante, Luke W. Naylor

United States Geological Survey: Staff Publications

We used satellite telemetry to study autumn migration timing, routes, stopover duration, and final destinations of mallards Anas platyrhynchos captured the previous spring in Arkansas from 2004 to 2007. Of those mallards that still had functioning transmitters on September 15 (n = 55), the average date when autumn migration began was October 23 (SE = 2.62 d; range = September 17–December 7). For those mallards that stopped for .1 d during migration, the average stopover length was 15.4 d (SE = 1.47 d). Ten mallards migrated nonstop to wintering sites. The eastern Dakotas were a heavily utilized stopover area. The …


Chemical Contaminants As Stratigraphic Markers For The Anthropocene, Michael A. Kruge Dec 2012

Chemical Contaminants As Stratigraphic Markers For The Anthropocene, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Thousands and even millions of years from now, widespread anthropogenic contaminants in sediments would likely persist, incorporated into the geological record. They would inadvertently preserve evidence of our present era (informally designated as the Anthropocene Epoch) characterized by large human populations engaged in intensive industrial and agricultural activities.

Hypothetical geologists in the distant future would likely find unusually high concentrations of a wide variety of contaminants at stratigraphic levels corresponding to our present time, analogous to the iridium anomaly marking the bolide impact event at the close of the Cretaceous Period. These would include both organic and inorganic substances, such …


Temporal And Crustal Effects On Differentiation Of Tholeiite To Calcalkaline And Ferro-Trachytic Suites, High Lava Plains, Oregon, Usa, Martin J. Streck, Anita L. Grunder Nov 2012

Temporal And Crustal Effects On Differentiation Of Tholeiite To Calcalkaline And Ferro-Trachytic Suites, High Lava Plains, Oregon, Usa, Martin J. Streck, Anita L. Grunder

Geology Faculty Publications and Presentations

Strongly bimodal, basalt-rhyolite volcanism of the High Lava Plains Province of Oregon followed the Middle Miocene flood basalts of the Pacific Northwest and extends to recent time. During the 8 m.y. of volcanism recorded in the central High Lava Plains, in western Harney Basin, three distinct mafic magmatic trends originate from primitive high-alumina olivine tholeiites (HAOT); they are tholeiitic, calcalkaline and ferro-trachytic. Tholeiitic basalts occur throughout the history and their compositions are derived by crystal fractionation while traversing the crust and mixing with evolved mafic magmas. Scavenging of apatite from crustal rocks and minor contamination with felsic melts accounts for …


Gps Constraints On Indo-Asian Convergence In The Bhutan Himalaya: Segmentation And Potential For A 8.2-8.8 Mw Earthquake, Dowchu Drukpa, Phuntsho Pelgay, Anjan Bhattacharya, Phillipe Vernant, Walter Szeliga, Roser Bilham Nov 2012

Gps Constraints On Indo-Asian Convergence In The Bhutan Himalaya: Segmentation And Potential For A 8.2-8.8 Mw Earthquake, Dowchu Drukpa, Phuntsho Pelgay, Anjan Bhattacharya, Phillipe Vernant, Walter Szeliga, Roser Bilham

Faculty Scholarship for the Cascadia Hazards Institute

The seismogenic setting of Bhutan is unusual due to its lower-than-average 20th century seismic moment release (Drukpa et al. 2006), its absence of a reliable historical record, and its unusual location near the Shillong plateau where a great earthquake in 1897 resulted in ≈10 m of N/S shortening of the Indian plate to its south (Gahalaut et al. 2011). Despite these indicators that lower than normal convergence velocities should currently prevail, the GPS velocity between Shillong and Lhasa suggests that convergence in Sikkim and Bhutan occurs at velocities exceeding 20 mm/yr. GPS points between the Greater Himalaya and the Shillong …


Injecting Large Volumes Of Preformed Particle Gel For Water Conformance Control, Baojun Bai, Mingzhen Wei, Yuzhang Liu Nov 2012

Injecting Large Volumes Of Preformed Particle Gel For Water Conformance Control, Baojun Bai, Mingzhen Wei, Yuzhang Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This paper describes Preformed Particle Gel (PPG) treatments for in-depth fluid diversion in four injection wells located in the northern section of the Lamadian reservoir, Daqing oilfield, China, which is a sandstone reservoir with thick heterogeneous pay zones. Forty-six producers were connected to the four treated injectors with an average water cut of 95.4% before PPG treatments. A large volume (more than 1 000 m3) of PPG suspension with concentrations of 1 900-2 500 mg/L and particle sizes of 0.06-3.0 mm was injected into each well, each injection spanning approximately four months. The injection PPG suspension volumes range …


Applicability And Estimation Of Error For Determination Of Hydraulic Conductivity Values Based Upon Traditional Aquifer Test Methods For 2-D Groundwater Modeling, Timothy W. Freed Sr. Oct 2012

Applicability And Estimation Of Error For Determination Of Hydraulic Conductivity Values Based Upon Traditional Aquifer Test Methods For 2-D Groundwater Modeling, Timothy W. Freed Sr.

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Theis method and its derivative Cooper-Jacob method are commonly used for determining hydraulic conductivity (K) for aquifer studies using two-dimensional (2-D) groundwater modeling. Theis and derivative equations assume isotropic, homogeneous aquifers and horizontal flow. In nature, saturated permeable layers of an aquifer are often separated by less permeable layers or lenses, which commonly have K's that are lower by several orders of magnitude. The presence of such geologic features induces vertical flow during aquifer tests violating assumptions for Theis based methods. This study assesses the appropriateness and error of using Theis based equations to determine K for use in …


Geologic Observations Along The Steamboat Trace Trail, Markers 16-20, In The Vicinity Of Peru, Nemaha County, Nebraska (Including On The Indian Cave Sandstone), Robert F. Diffendal Jr. Oct 2012

Geologic Observations Along The Steamboat Trace Trail, Markers 16-20, In The Vicinity Of Peru, Nemaha County, Nebraska (Including On The Indian Cave Sandstone), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

This section of the Steamboat Trace Trail from markers 16 through 20 (Figure 1) offers especially good examples of geologic features in this part of Nebraska (Figure 2). These include: The Missouri River, its valley, river cuts into the valley side, tributaries to the river, and flood control structures; Sites of active and potential landslides; Wind-deposited silts (called loess by geologists and soil scientists); Glacial deposits; Bedrock exposures of ancient sandstone, shale, conglomerate, and limestone; Fossils of ocean- and land-dwelling plants and animals; Coal deposits.


Tectonics And Sedimentary Facies Interpretation Of The Mesozoic Giron Group, Colombia, Hernando Martinez-Sacristan, Ricardo Mier-Umana, Nazrul I. Khandaker, Stanley Schleifer, Diana Lucia Leon-Martinez Oct 2012

Tectonics And Sedimentary Facies Interpretation Of The Mesozoic Giron Group, Colombia, Hernando Martinez-Sacristan, Ricardo Mier-Umana, Nazrul I. Khandaker, Stanley Schleifer, Diana Lucia Leon-Martinez

Publications and Research

Preliminary field investigations involving exposed Giron Group sediments in Colombia provided some interesting geologic information in terms of provenance, depositional environments, and development of the Mesozoic synrift sedimentary basins in Colombia. Overall, the synrift Triassic-Jurassic rift-related volcanic rocks, redbeds, and evaporites are prominent in Colombia, and a thick basin sequence of Cretaceous sandstones and shales dominates the central part of the Cordillera Oriental. These were mostly deposited in dominantly north-trending grabens. Identified sedimentary rock types were arkose, clast-and-matrix-supported conglomerate, red mudstone, variegated sandstone, siltstone and breccia. Extensive kaolinitization was noticeable in several sandstone samples. Among the notable sedimentary structures were …


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 Oct 2012

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 …


Geogram 2012, David J. Keeling, Wku Department Of Geography And Geology Oct 2012

Geogram 2012, David J. Keeling, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Catching Air - Those Magnificent Jumping Suwannee Sturgeons, Ken Sulak Oct 2012

Catching Air - Those Magnificent Jumping Suwannee Sturgeons, Ken Sulak

United States Geological Survey: Staff Publications

It starts deep at the bottom of the dark silent river, three to four powerful tail beats and three sharp acoustic clicks. Then, a sudden upturn of the body and the fish explodes upward, 100 pounds going vertical, catching air, lots of air. A good jump can power a big fish, six to nine feet into the air. You have to be quick to get a photo, hang time is only about a second, but an accomplished jump by a big old Suwannee River Gulf Sturgeon is impressive; a magnificent display of power. The exit is almost vertical. The tail …


Tsunamis: Desprevenidos Por La Realidad De La Geología Un Estudio De La Posibilidad Y Precauciones Por Un Tsunami En Puerto López, Manabí, Ecuador, Abigail Eurich Oct 2012

Tsunamis: Desprevenidos Por La Realidad De La Geología Un Estudio De La Posibilidad Y Precauciones Por Un Tsunami En Puerto López, Manabí, Ecuador, Abigail Eurich

Independent Study Project (ISP) Collection

Tsunamis occur in the Pacific Ocean about once every 1.5 years (Berninghausen, 1962). Forty-nine Tsunamis are recorded to have hit the western coast of South America since 1562, though only 3 hit the coast of Ecuador specifically (Berninghausen, 1962). However, it is still important to recognize the possibility of having a tsunami in Ecuador and plan accordingly. On a very complex junction of the Nazca and South American plate, with the Nazca and Carnegie Ridges as well as the Galapagos hotspot, this part of the world is apt to many earthquakes, submarine landslides, and volcanic activity which all have the …


The Geologic Records Of Dust In The Quaternary, Daniel R. Muhs Sep 2012

The Geologic Records Of Dust In The Quaternary, Daniel R. Muhs

United States Geological Survey: Staff Publications

Study of geologic records of dust composition, sources and deposition rates is important for understanding the role of dust in the overall planetary radiation balance, fertilization of organisms in the world’s oceans, nutrient additions to the terrestrial biosphere and soils, and for paleoclimatic reconstructions. Both glacial and non-glacial processes produce fine-grained particles that can be transported by the wind. Geologic records of dust flux occur in a number of depositional archives for sediments: (1) loess deposits; (2) lake sediments; (3) soils; (4) deep-ocean basins; and (5) ice sheets and smaller glaciers. These archives have several characteristics that make them highly …


Whose Islands Are These Anyway?, David J. Keeling Sep 2012

Whose Islands Are These Anyway?, David J. Keeling

Earth, Environmental, and Atmospheric Sciences Faculty Publications

This opinion piece addresses Argentina's growing political rhetoric about its claims to the Malvians/Falkland Islands in the South Atlantic.


Bioactive Trace Metal Distributions And Biogeochemical Controls In The Southern Ocean, Christopher Measures, Mariko Hatta, Maxime Grand Sep 2012

Bioactive Trace Metal Distributions And Biogeochemical Controls In The Southern Ocean, Christopher Measures, Mariko Hatta, Maxime Grand

Faculty Publications

Extensive sampling in many regions of the Southern Ocean has demonstrated that surface water concentrations of dissolved Fe are low enough to limit phytoplankton growth. In contrast, there is currently no evidence that other bioactive elements (e.g., Mn, Zn, Co) are similarly limiting. Although atmospheric input of dissolved Fe to Southern Ocean surface waters appears to be low, resuspension of sediments from shallow regions around islands and the Antarctic coastline can inject significant amounts of Fe into the surrounding waters, stimulating primary production and providing a natural laboratory for studying the response of biological systems to natural Fe fertilization processes. …


Cascadia Fore Arc Seismic Survey: Open-Access Data Available, W. Steven Holbrook, Graham Kent, Katie Keranan, H. Paul Johnson, Anne Trehu, Harold Tobin, Jacqueline Caplan-Auerbach, Jeff Beeson Sep 2012

Cascadia Fore Arc Seismic Survey: Open-Access Data Available, W. Steven Holbrook, Graham Kent, Katie Keranan, H. Paul Johnson, Anne Trehu, Harold Tobin, Jacqueline Caplan-Auerbach, Jeff Beeson

Geology Faculty Publications

The Cascadia subduction zone (CSZ), where the Juan de Fuca and Gorda plates subduct obliquely beneath North America at a rate of about 35 millimeters per year, poses major geological hazards to population centers of the northwestern United States. Despite the importance of the subducting slab in these hazards, the plate boundary is poorly mapped and understood, especially offshore.


A New Model For The Spectral Induced Polarization Signature Of Bacterial Growth In Porous Media, Andre Revil, Estella A. Atekwana, C. Zhang, Abderrahim Jardani, Schaun M. Smith Sep 2012

A New Model For The Spectral Induced Polarization Signature Of Bacterial Growth In Porous Media, Andre Revil, Estella A. Atekwana, C. Zhang, Abderrahim Jardani, Schaun M. Smith

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The complex conductivity of porous materials and colloidal suspensions comprises two components: an in-phase conductivity associated with electromigration of the charge carriers and a quadrature conductivity associated with the reversible storage of the charges at some polarization length scales. We developed a quantitative model to investigate the frequency domain induced polarization response of suspensions of bacteria and bacteria growth in porous media. Induced polarization of bacteria (α polarization) is related to the properties of the electrical double layer of the bacteria. Surface conductivity and α polarization are due to the Stern layer of counterions occurring in a brush of polymers …


Nebraska's Wetlands: Their Wildlife And Ecology, Paul A. Johnsgard Sep 2012

Nebraska's Wetlands: Their Wildlife And Ecology, Paul A. Johnsgard

Conservation and Survey Division

1 An Overview of Nebraska's Wetlands

2 The Missouri Valley • Natural History Profiles of Some Missouri Valley Wetland Species • The Missouri Valley Wetlands

3 The Niobrara Valley Region • Natural History Profiles of Some Niobrara Valley Wetland Species • The Niobrara Valley Wetlands

4 The Platte Valley Region • Natural History Profiles of Some Platte Valley Wetland Species • The Central Platte Valley Wetlands • The North Platte Valley Wetlands

5 Other River Valley Wetlands • Natural History Profiles of Some Typical Riverine Species • The Elkhorn Valley Wetlands • The Loup Valley Wetlands • The Republican Valley …


Interseismic Strain Accumulation Along The Western Boundary Of The Indian Subcontinent, Walter Szeliga, Roger Bilham, Din Mohammad Kakar, Sarosh H. Lodi Aug 2012

Interseismic Strain Accumulation Along The Western Boundary Of The Indian Subcontinent, Walter Szeliga, Roger Bilham, Din Mohammad Kakar, Sarosh H. Lodi

All Faculty Scholarship for the College of the Sciences

Despite an overall sinistral slip rate of ≈3 cm/yr, few major earthquakes have occurred in the past 200 years along the Chaman fault system, the western boundary of the India Plate with the Eurasia Plate. GPS and InSAR data reported here indicate sinistral shear velocities of 8–17 mm/yr across the westernmost branches of the fault system, suggesting that a significant fraction of the plate boundary slip is distributed in the fold and fault belt to the east. At its southernmost on‐land segment (≈26°N), near the triple junction between the Arabia, Eurasia, and India Plates, we find the velocity across the …


Raman Mapping Of Mars Relevant Minerals Using Multiple Excitation Wavelenghts, Victoria Campbell, William Abbey Aug 2012

Raman Mapping Of Mars Relevant Minerals Using Multiple Excitation Wavelenghts, Victoria Campbell, William Abbey

STAR Program Research Presentations

The purpose of this project is to map Mars relevant minerals using the Raman instrument Horiba LabRam Raman. The Raman spectrometer is a non-invasive sampling technique used to identify mineral composition of various compositions by measuring the “Raman Shift” of each mineral. This was accomplished by using a green (532nm) laser which acted as a monochromatic light source. This source was absorbed by the sample and reemitted. The frequency of the reemitted photons are then shifted up or down in comparison with original frequency, which is referred to as the ‘Raman Effect’. The samples with shorter wavelengths produced a stronger …


Chronostratigraphic Framework For The Iodp Expedition 318 Cores From The Wilkes Land Margin: Constraints For Paleoceanographic Reconstruction, Lisa Tauxe, Catherine E. Stickley, Saiko Sugisaki, Peter K. Bijl, Steven M. Bohaty, Henk Brinkhuis, Carlota Escutia, J. A. Flores, A. J. P. Houben, M. Iwai, Francisco J. Jiménez‐Espejo, Robert Mckay, Sandra Passchier, Jörg Pross, Christina Riesselman, Ursula Röhl, Francesca Sangiorgi, Kevin Welsh, Adam Klaus, Annick Fehr, James Bendle, Robert B. Dunbar, J. Gonzàlez, T. Hayden, K. Katsuki, M. P. Olney, Stephen Pekar, P. K. Shrivastava, Tina Van De Flierdt, Trevor Williams, M. Yamane Jun 2012

Chronostratigraphic Framework For The Iodp Expedition 318 Cores From The Wilkes Land Margin: Constraints For Paleoceanographic Reconstruction, Lisa Tauxe, Catherine E. Stickley, Saiko Sugisaki, Peter K. Bijl, Steven M. Bohaty, Henk Brinkhuis, Carlota Escutia, J. A. Flores, A. J. P. Houben, M. Iwai, Francisco J. Jiménez‐Espejo, Robert Mckay, Sandra Passchier, Jörg Pross, Christina Riesselman, Ursula Röhl, Francesca Sangiorgi, Kevin Welsh, Adam Klaus, Annick Fehr, James Bendle, Robert B. Dunbar, J. Gonzàlez, T. Hayden, K. Katsuki, M. P. Olney, Stephen Pekar, P. K. Shrivastava, Tina Van De Flierdt, Trevor Williams, M. Yamane

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

[1] The Integrated Ocean Drilling Program Expedition 318 to the Wilkes Land margin of Antarctica recovered a sedimentary succession ranging in age from lower Eocene to the Holocene. Excellent stratigraphic control is key to understanding the timing of paleoceanographic events through critical climate intervals. Drill sites recovered the lower and middle Eocene, nearly the entire Oligocene, the Miocene from about 17 Ma, the entire Pliocene and much of the Pleistocene. The paleomagnetic properties are generally suitable for magnetostratigraphic interpretation, with well‐behaved demagnetization diagrams, uniform distribution of declinations, and a clear separation into two inclination modes. Although the sequences were discontinuously …


North Central Region Soil Survey Conference Field Tour Jun 2012

North Central Region Soil Survey Conference Field Tour

Conservation and Survey Division

No abstract provided.


Seismic Site Classifications For The St. Louis Urban Area, Jaewon Chung, J. David Rogers Jun 2012

Seismic Site Classifications For The St. Louis Urban Area, Jaewon Chung, J. David Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Regional National Earthquake Hazards Reduction Program (NEHRP) soil class maps have become important input parameters for seismic site characterization and hazard studies. The broad range of shallow shear-wave velocity (VS30, the average shear-wave velocity in the upper 30 m) measurements in the St. Louis area results in significant uncertainties between the actual spot values and the averaged values used to assign NEHRP soil classes for regional seismic hazard studies. In the preparation of an NEHRP site classification map of the St. Louis urban area, we analyzed 92 shear-wave velocity (VS) measurements, supplemented by 1400+ standard penetration …


4th International Union Of Soil Sciences Soil Classification Conference Field Tour Guidebook Jun 2012

4th International Union Of Soil Sciences Soil Classification Conference Field Tour Guidebook

Conservation and Survey Division

No abstract provided.


Map Of The Late Quaternary Active Kern Canyon And Breckenridge Faults, Southern Sierra Nevada, California, C. C. Brossy, K. I. Kelson, Colin B. Amos, J. N. Baldwin, B. Kozlowicz, D. Simpson, M. G. Ticci, A. T. Lutz, O. Kozaci, A. Streig, R. Turner, R. Rose Jun 2012

Map Of The Late Quaternary Active Kern Canyon And Breckenridge Faults, Southern Sierra Nevada, California, C. C. Brossy, K. I. Kelson, Colin B. Amos, J. N. Baldwin, B. Kozlowicz, D. Simpson, M. G. Ticci, A. T. Lutz, O. Kozaci, A. Streig, R. Turner, R. Rose

Geology Faculty Publications

Surface traces of the Quaternary active Kern Canyon and Breckenridge faults were mapped via aerial reconnaissance, analysis of light detection and ranging (LiDAR) elevation data, review and interpretation of aerial photography, field reconnaissance, and detailed field mapping. This effort specifically targeted evidence of late Quaternary surface deformation and, combined with separate paleoseismic investigations, identified and characterized the North Kern Canyon, South Kern Canyon, and Lake Isabella sections of the Kern Canyon fault and the Breckenridge fault. The mapping presented here provides definitive evidence for previously unrecognized Holocene and late Pleistocene east-down displacement along the Kern Canyon and Breckenridge faults. Our …


Monitoring Glacier Surface Seismicity In Time And Space Using Rayleigh Waves, T. D. Mikesell, K. Van Wijk, M. M. Haney, J. H, Bradford, H. P. Marshall, Joel T. Harper May 2012

Monitoring Glacier Surface Seismicity In Time And Space Using Rayleigh Waves, T. D. Mikesell, K. Van Wijk, M. M. Haney, J. H, Bradford, H. P. Marshall, Joel T. Harper

Geosciences Faculty Publications

Sliding glaciers and brittle ice failure generate seismic body and surface wave energy characteristic to the source mechanism. Here we analyze continuous seismic recordings from an array of nine short-period passive seismometers located on Bench Glacier, Alaska (USA) (61.033N, 145.687W). We focus on the arrival-time and amplitude information of the dominant Rayleigh wave phase. Over a 46-hour period we detect thousands of events using a cross-correlation based event identification method. Travel-time inversion of a subset of events (7% of the total) defines an active crevasse, propagating more than 200 meters in three hours. From the Rayleigh wave amplitudes, we estimate …


Atmospheric Circulation Change In The Central Himalayas Indicated By A High-Resolution Ice Core Deuterium Excess Record, Hongxi Pang, Shugui Hou, Susan Kaspari, Paul Mayewski, Douglas Introne, Valérie Masson-Delmotte, Jean Jouzel, Zhenchao Li, Yuanqing He, Sungmin Hong, Dahe Qin May 2012

Atmospheric Circulation Change In The Central Himalayas Indicated By A High-Resolution Ice Core Deuterium Excess Record, Hongxi Pang, Shugui Hou, Susan Kaspari, Paul Mayewski, Douglas Introne, Valérie Masson-Delmotte, Jean Jouzel, Zhenchao Li, Yuanqing He, Sungmin Hong, Dahe Qin

All Faculty Scholarship for the College of the Sciences

Continuous measurements of both δD and δ18O were performed along a 108.8 m ice core recovered from the East Rongbuk Glacier on the northeast saddle of Mt. Qomolangma (Everest) (28.03° N, 86.96° E, 6518 m above sea level) in September 2002. They provide the first high-resolution historical record of deuterium excess (d) in the central Himalayas. In this paper, we focus on d variability from 1951 to 2001 and its relationship with large scale atmospheric circulation. The d record exhibits significant seasonal variations, with low values in summer and high values in winter, reflecting the atmospheric circulation shift between winter …


High-Resolution Correlation Of The Upper Cretaceous Stratigraphy Between The Book Cliffs And The Western Henry Mountains Syncline, Utah, U.S.A., Drew L. Seymour May 2012

High-Resolution Correlation Of The Upper Cretaceous Stratigraphy Between The Book Cliffs And The Western Henry Mountains Syncline, Utah, U.S.A., Drew L. Seymour

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

This study presents high-resolution correlations of the Upper Cretaceous stratigraphy between the Book Cliffs and the western Henry Mountains Syncline in Utah. The objective of this study is to understand changes in patterns of regional sediment dispersal during the Late Cretaceous on the western margin of the Cretaceous Western Interior Seaway. The intensely studied Book Cliffs consist of formations deposited in terrestrial, marginal-marine, and open-marine environments. A composite section was logged at Coal Canyon near Green River, UT. The western Henry Mountains Syncline is located in south-central Utah ~135 km S-SW of Coal Canyon. A composite section was logged at …


Road Dust Lead (Pb) In Two Neighborhoods Of Urban Atlanta, (Ga, Usa), Daniel Deocampo Ph.D, Phillip Jack Reed, Alexander P. Kalenuik May 2012

Road Dust Lead (Pb) In Two Neighborhoods Of Urban Atlanta, (Ga, Usa), Daniel Deocampo Ph.D, Phillip Jack Reed, Alexander P. Kalenuik

Geosciences Faculty Publications

Road dust continues to be a major potential reservoir of Pb in the urban environment, and an important potential component of child Pb exposure. This study presents ICP-AES analyses of metals in 72 samples of road dust (<250 μm) collected in the urban core of Atlanta, Georgia. In the Downtown area, median Pb concentrations are ~63 mg/kg Pb, with high values of 278 mg/kg. For comparison, median Pb values in a nearby residential neighborhood (also in the urban core) were ~93 mg/kg, with a high of 972 mg/kg. Geospatial variability is high, with significant variation observed over tens to hundreds of meters. Spearman Rank Correlation tests suggest that Pb and other metals (Cu, Ni, V, Zn) are associated with iron and manganese oxide phases in the residential area, as reported in other cities. However, Pb in the Downtown area is not correlated with the others, suggesting a difference in source or transport history. Given these complexities and the expected differences between road dust and soil Pb, future efforts to assess exposure risk should therefore be based on spatially distributed sampling at very high spatial resolution.