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A History Of Wright State University's Department Of Geological Science, Paul J. Wolfe Jan 2022

A History Of Wright State University's Department Of Geological Science, Paul J. Wolfe

Earth and Environmental Sciences Faculty Publications

A history of Wright State University's disbanded and reintegrated Department of Geological Sciences written by department faculty member Paul J. Wolfe. Wolfe describes the development of the program, the faculty throughout the years, and the programs offered through the department.


Removal Of The Northern Paleo-Teton Range Along The Yellowstone Hotspot Track, J. Ryan Thigpen, Summer J. Brown, Autumn L. Helfrich, Rachel Hoar, Michael M. Mcglue, Edward W. Woolery, William R. Guenthner, Meredith L. Swallom, Spencer Dixon, Sean Gallen Oct 2021

Removal Of The Northern Paleo-Teton Range Along The Yellowstone Hotspot Track, J. Ryan Thigpen, Summer J. Brown, Autumn L. Helfrich, Rachel Hoar, Michael M. Mcglue, Edward W. Woolery, William R. Guenthner, Meredith L. Swallom, Spencer Dixon, Sean Gallen

Earth and Environmental Sciences Faculty Publications

Classically held mechanisms for removing mountain topography (e.g., erosion and gravitational collapse) require 10-100 Myr or more to completely remove tectonically generated relief. Here, we propose that mountain ranges can be completely and rapidly (< 2 Myr) removed by a migrating hotspot. In western North America, multiple mountain ranges, including the Teton Range, terminate at the boundary with the relatively low relief track of the Yellowstone hotspot. This abrupt transition leads to a previously untested hypothesis that preexisting mountainous topography along the track has been erased. We integrate thermochronologic data collected from the footwall of the Teton fault with flexural-kinematic modeling and length-displacement scaling to show that the paleo-Teton fault and associated Teton Range was much longer (min. original length 190-210 km) than the present topographic expression of the range front (~65 km) and extended across the modern-day Yellowstone hotspot track. These analyses also indicate that the majority of fault displacement (min. 11.4-12.6 km) and the associated footwall mountain range growth had accumulated prior to Yellowstone encroachment at ~2 Ma, leading us to interpret that eastward migration of the Yellowstone hotspot relative to stable North America led to removal of the paleo-Teton mountain topography via posteruptive collapse of the range following multiple supercaldera (VEI 8) eruptions from 2.0 Ma to 600 ka and/or an isostatic collapse response, similar to ranges north of the Snake River plain. While this extremely rapid removal of mountain ranges and adjoining basins is probably relatively infrequent in the geologic record, it has important implications for continental physiography and topography over very short time spans.


Tectonic Transport Directions, Shear Senses And Deformation Temperatures Indicated By Quartz C-Axis Fabrics And Microstructures In A Nw-Se Transect Across The Moine And Sgurr Beag Thrust Sheets, Caledonian Orogen Of Northern Scotland, Richard D. Law, J. Ryan Thigpen, Sarah E. Mazza, Calvin A. Mako, Maarten Krabbendam, Brandon M. Spencer, Kyle T. Ashley, Robin A. Strachan, Ella F. Davis Sep 2021

Tectonic Transport Directions, Shear Senses And Deformation Temperatures Indicated By Quartz C-Axis Fabrics And Microstructures In A Nw-Se Transect Across The Moine And Sgurr Beag Thrust Sheets, Caledonian Orogen Of Northern Scotland, Richard D. Law, J. Ryan Thigpen, Sarah E. Mazza, Calvin A. Mako, Maarten Krabbendam, Brandon M. Spencer, Kyle T. Ashley, Robin A. Strachan, Ella F. Davis

Earth and Environmental Sciences Faculty Publications

Moine metasedimentary rocks of northern Scotland are characterized by arcuate map patterns of mineral lineations that swing progressively clockwise from orogen-perpendicular E-trending lineations in greenschist facies mylonites above the Moine thrust on the foreland edge of the Caledonian Orogen, to S-trending lineations at higher structural levels and metamorphic grades in the hinterland. Quartz c-axis fabrics measured on a west to east coast transect demonstrate that the lineations developed parallel to the maximum principal extension direction and therefore track the local tectonic transport direction. Microstructures and c-axis fabrics document a progressive change from top to the N shearing in the hinterland …


Climate, Vegetation, And Weathering Across Space And Time In Lake Tanganyika (Tropical Eastern Africa), Sarah J. Ivory, Michael M. Mcglue, Cara Peterman, Patrick Baldwin, Joseph Lucas, Andrew Cohen, James Russell, Justina Saroni, Emma Msaky, Ishmael Kimirei, Michael Soreghan Feb 2021

Climate, Vegetation, And Weathering Across Space And Time In Lake Tanganyika (Tropical Eastern Africa), Sarah J. Ivory, Michael M. Mcglue, Cara Peterman, Patrick Baldwin, Joseph Lucas, Andrew Cohen, James Russell, Justina Saroni, Emma Msaky, Ishmael Kimirei, Michael Soreghan

Earth and Environmental Sciences Faculty Publications

Climate and vegetation influence weathering rates and processes; however, evaluating the effects of each and feedbacks between systems, has yet to be accomplished for many types of landscapes. A detailed understanding of how these processes interact to shape landscapes is particularly crucial for reconciling future scenarios of changing climate, where profound alterations to both the biosphere and geosphere are anticipated. In the tropics, ecosystem services, such as soil and water quality, are linked to both vegetation and weathering processes that form a strong control on natural resources that are the foundation of many communities’ daily subsistence. This understanding is further …


Artisanal Ceramic Factories Using Wood Combustion: A Nanoparticles And Human Health Study, Kátia Martinello, James C. Hower, Diana Pinto, Carlos E. Schnorr, Guilherme L. Dotto, Marcos Leandro Silva Oliveira, Claudete Gindri Ramos Jan 2021

Artisanal Ceramic Factories Using Wood Combustion: A Nanoparticles And Human Health Study, Kátia Martinello, James C. Hower, Diana Pinto, Carlos E. Schnorr, Guilherme L. Dotto, Marcos Leandro Silva Oliveira, Claudete Gindri Ramos

Earth and Environmental Sciences Faculty Publications

The ceramics industry, resulting from developments of modern compounds, is a segment of great influence in worldwide sustainability. Artisanal ceramic factories based on wood combustion have significant risks for the creation and discharge of atmosphere nanoparticles (NPs) and ultra-fine particles (UFPs). At present, there is insufficient recognition on the influence of engineered-NPs on the atmosphere and health. Real improvements are indispensable to diminish contact with NPs. The present study demonstrates the main NPs and UFPS present in an area of intense artisanal wood-combustion ceramic manufacturing. Particulate matter was sampled for morphological, chemical, and geochemical studies by sophisticated electron microbeam microscopy, …


Deposition Of Nanoparticles On School Eyeglasses In Urban And Rural Areas: A Methodology For A More Real Assessment Of The Possible Impacts, Ḱtia Martinello, James C. Hower, Guilherme L. Dotto, Claudete Gindri Ramos, Carlos E. Schnorr, Diana Pinto Jan 2021

Deposition Of Nanoparticles On School Eyeglasses In Urban And Rural Areas: A Methodology For A More Real Assessment Of The Possible Impacts, Ḱtia Martinello, James C. Hower, Guilherme L. Dotto, Claudete Gindri Ramos, Carlos E. Schnorr, Diana Pinto

Earth and Environmental Sciences Faculty Publications

Because incomplete confirmation is available concerning the influential role of atmosphere contamination on conjunctivitis, myopia, asthma, and allergic rhinitis in Brazil, the focus of the present work is to explore the possible relations among atmosphere contamination and eye problems. Rather that a case study on eye diseases, by way of questionnaires supplemented by the investigation of nanoparticles (NPs) on eyeglasses, the study examines the mechanisms in which NPs and ultra-fine particles are deposited on the glasses of children up to 10 years of age in urban and rural area. The important connection between atmosphere contaminants and individual protection equipment justifies …


Solar Irradiance And Enso Affect Food Security In Lake Tanganyika, A Major African Inland Fishery, Michael M. Mcglue, S. J. Ivory, J. R. Stone, A. S. Cohen, T. M. Kamulali, J. C. Latimer, M. A. Brannon, I. A. Kimirei, M. J. Soreghan Oct 2020

Solar Irradiance And Enso Affect Food Security In Lake Tanganyika, A Major African Inland Fishery, Michael M. Mcglue, S. J. Ivory, J. R. Stone, A. S. Cohen, T. M. Kamulali, J. C. Latimer, M. A. Brannon, I. A. Kimirei, M. J. Soreghan

Earth and Environmental Sciences Faculty Publications

Food security in a warming world is a grave concern for rapidly growing impoverished populations. Low-latitude inland fisheries provide protein for millions of rural poor, yet the impacts of high-frequency climate oscillations on these aquatic ecosystems are unknown. Here, we present a sub-annual-to-annual resolution paleolimnological reconstruction of upwelling, productivity, and algal composition at Lake Tanganyika, one of Africa's largest landlocked fisheries. The data reveal increases in diatom production at centennial-scale solar irradiance maxima, and interannual variability in upwelling linked to La Niña. Our study shows that interactions between global climatic controls and El Niño-Southern Oscillation teleconnections exert profound influences on …


“Enriching Lives Within Sedimentary Geology”: Actionable Recommendations For Making Sepm A Diverse, Equitable And Inclusive Society For All Sedimentary Geologists, R.C. Mahon, A.M. Fernandes, A. Abeyta, R. Martindale, K.D Bergman, C. Jackson, Et Al Sep 2020

“Enriching Lives Within Sedimentary Geology”: Actionable Recommendations For Making Sepm A Diverse, Equitable And Inclusive Society For All Sedimentary Geologists, R.C. Mahon, A.M. Fernandes, A. Abeyta, R. Martindale, K.D Bergman, C. Jackson, Et Al

Earth and Environmental Sciences Faculty Publications

Innovative science benefits from diversity of thought and influence at all waypoints along the scientific journey, from early education to career-length contributions in research and mentorship. Scientific societies, like the Society for Sedimentary Geology (SEPM), steward their innovators and the direction of the science, thereby defining the societal impact and evolution of a discipline. They are uniquely positioned to promote the representation and success of all scientists, including those from minoritized populations, through proactive advocacy, and inclusive mentorship, awards, and leadership. We introspectively review available records of SEPM membership, leadership, awardees, and editorial boards to identify areas for growth and …


Probability Distributions Of Particle Hop Distance And Travel Time Over Equilibrium Mobile Bedforms, Robert C. Mahon, Ashley C. Thomas, Suleyman Naqshband, Kate C. P. Leary, Brandon Mcelroy Jul 2020

Probability Distributions Of Particle Hop Distance And Travel Time Over Equilibrium Mobile Bedforms, Robert C. Mahon, Ashley C. Thomas, Suleyman Naqshband, Kate C. P. Leary, Brandon Mcelroy

Earth and Environmental Sciences Faculty Publications

The joint probability distribution of streamwise particle hop distance, lateral particle hop distance, and travel time constrains the relationships between topographic change and sediment transport at the granular scale. Previous studies have investigated the ensemble characteristics of particle motions over plane bed topography; however, it is unclear whether reported distributions remain valid when bedforms are present. Here, we present measurements of particle motion over bedform topography obtained in a laboratory flume and compare these to particle motions over plane bed topography with otherwise similar conditions. We find substantial differences in particle motion in the presence of bedforms that …


Nanomineralogy Of Evaporative Precipitation Of Efflorescent Compounds From Coal Mine Drainage, Luis F. O. Silva, Diana Pinto, Guilherme L. Dotto, James C. Hower Jun 2020

Nanomineralogy Of Evaporative Precipitation Of Efflorescent Compounds From Coal Mine Drainage, Luis F. O. Silva, Diana Pinto, Guilherme L. Dotto, James C. Hower

Earth and Environmental Sciences Faculty Publications

Efflorescent nanophases (NPs) are found as a transitory accumulation of potentially hazardous elements (PHEs), particularly in tropical climates. The central objective of this study was to investigate the distribution of PHEs with NPs through the evaporative formation structures (EFS) of enormously PHEs-rich coal-mine drainages (CMD). The EFS were studied in natural coal mine drainage for five months in order to determine their geochemical and ecological structures and to assess their position in the reduction of PHEs in nature. The largest coal-fired power plant in South America, located in south Brazil, is used as an example of such a problem. In …


Direct Inversion Method Of Fault Slip Analysis To Determine The Orientation Of Principal Stresses And Relative Chronology For Tectonic Events In Southwestern White Mountain Region Of New Hampshire, Usa, Christopher C. Barton, Jacques Angelier Jan 2020

Direct Inversion Method Of Fault Slip Analysis To Determine The Orientation Of Principal Stresses And Relative Chronology For Tectonic Events In Southwestern White Mountain Region Of New Hampshire, Usa, Christopher C. Barton, Jacques Angelier

Earth and Environmental Sciences Faculty Publications

The orientation and relative magnitudes of paleo tectonic stresses in the western central region of the White Mountains of New Hampshire is reconstructed using the direct inversion method of fault slip analysis on 1–10-m long fractures exposed on a series of road cuts along Interstate 93, just east of the Hubbard Brook Experimental Forest in North Woodstock, NH, USA. The inversion yields nine stress regimes which identify five tectonic events that impacted the White Mountain region over the last 410 Ma. The inversion method has potential application in basin analysis


Increasing Expression Of Civic-Engagement Values By Students In A Service-Learning Chemistry Course, Audrey Mcgowin, Rebecca Teed Sep 2019

Increasing Expression Of Civic-Engagement Values By Students In A Service-Learning Chemistry Course, Audrey Mcgowin, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

A service-learning course at a midsized Midwestern research university was modified over a period of six years to integrate best-practice pedagogies that have been shown to increase civic engagement by students. Best-practice pedagogies included regular interaction with community partner(s), significant time spent on the service activity, and regular reflection (written and verbal) on the implications of the service activity. Besides water quality monitoring, students performed private well water analysis, wrote multiple formal reflection papers, and presented a public talk on the results of their project that included significant discussion time with community partners. Authentic expression of civic engagement values was …


Distributary Channel Networks As Moving Boundaries: Causes And Morphodynamic Effects, Robert C. Mahon, John B. Shaw, Wun-Tao Ke, Christopher A. Cathcart Jul 2019

Distributary Channel Networks As Moving Boundaries: Causes And Morphodynamic Effects, Robert C. Mahon, John B. Shaw, Wun-Tao Ke, Christopher A. Cathcart

Earth and Environmental Sciences Faculty Publications

We propose an exploratory model to describe the morphodynamics of distributary channel network growth on river deltas. The interface between deep channels and the shallow, unchannelized delta front deposits is modeled as a moving boundary. Steady flow over the unchannelized delta front is friction dominated and modeled by Laplace's equation. Shear stress along the network boundary produces nonlinear erosion rates at the interface, causing the boundary to move and network elements (channels and branches) to form. The model was run for boundary conditions resembling the Wax Lake Delta in coastal Louisiana, 20 parameterizations of sediment transport, and 3 …


A Historical Sedimentary Record Of Mercury In A Shallow Eutrophic Lake: Impacts Of Human Activities And Climate Change, Hanxiao Zhang, Shouliang Huo, Kevin M. Yeager, Beidou Xi, Jingtian Zhang, Fengchang Wu Apr 2019

A Historical Sedimentary Record Of Mercury In A Shallow Eutrophic Lake: Impacts Of Human Activities And Climate Change, Hanxiao Zhang, Shouliang Huo, Kevin M. Yeager, Beidou Xi, Jingtian Zhang, Fengchang Wu

Earth and Environmental Sciences Faculty Publications

Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding changes in pollution levels and thus trace anthropogenic or natural influences. This research investigates the 100-year history of mercury (Hg) deposition in sediments from Chao Lake, a shallow eutrophic lake in China. The results indicate that the Hg deposition history can be separated into three stages (pre-1960s, 1960s–1980s, and post-1980s) over the last 100 years. Before the 1960s, Hg concentrations in the sediment cores varied little and had no spatial difference. Since the …


Sh-Mode Seismic-Reflection Imaging Of Earthfill Dams, Edward W. Woolery Oct 2018

Sh-Mode Seismic-Reflection Imaging Of Earthfill Dams, Edward W. Woolery

Earth and Environmental Sciences Faculty Publications

Assessing subsurface characteristics and imaging geologic features (e.g., faults, cavities, low-velocity layers, etc.) are typical problems in near-surface geophysics. These questions often have adverse geotechnical engineering implications, and can be especially acute when associated with high-hazard structures such as large earthen flood-control dams. Dam-related issues are becoming more frequent in the United States, because a large part of this major infrastructure was designed and constructed in the early- to mid-twentieth century; these dams are thus passing into the latter stages of their design life, where minute flaws that were overlooked or thought to be insignificant in design/construction are now …


Lithologic Controls On Focused Erosion And Intraplate Earthquakes In The Eastern Tennessee Seismic Zone, Sean F. Gallen, J. Ryan Thigpen Sep 2018

Lithologic Controls On Focused Erosion And Intraplate Earthquakes In The Eastern Tennessee Seismic Zone, Sean F. Gallen, J. Ryan Thigpen

Earth and Environmental Sciences Faculty Publications

We present a new geomorphic model for the intraplate eastern Tennessee seismic zone (ETSZ). Previous studies document that the Upper Tennessee drainage basin is in a transient state of adjustment to ~150 m of base level fall that occurred in the Late Miocene. Using quantitative geomorphology, we demonstrate that base level fall resulted in the erosion of ~3,500 km3 of highly erodibility rock in an ~70 km wide by ~350‐km‐long corridor in the Paleozoic fold‐thrust belt above the ETSZ. Models of modern incision rates show a NE‐SW trending swath of elevated erosion ~30 km southeast of the center of …


Lake Regionalization And Diatom Metacommunity Structuring In Tropical South America, Xavier Benito, Sherilyn C. Fritz, Miriam Steinitz-Kannan, Maria I. Vélez, Michael M. Mcglue Aug 2018

Lake Regionalization And Diatom Metacommunity Structuring In Tropical South America, Xavier Benito, Sherilyn C. Fritz, Miriam Steinitz-Kannan, Maria I. Vélez, Michael M. Mcglue

Earth and Environmental Sciences Faculty Publications

Lakes and their topological distribution across Earth's surface impose ecological and evolutionary constraints on aquatic metacommunities. In this study, we group similar lake ecosystems as metacommunity units influencing diatom community structure. We assembled a database of 195 lakes from the tropical Andes and adjacent lowlands (8°N–30°S and 58–79°W) with associated environmental predictors to examine diatom metacommunity patterns at two different levels: taxon and functional (deconstructed species matrix by ecological guilds). We also derived spatial variables that inherently assessed the relative role of dispersal. Using complementary multivariate statistical techniques (principal component analysis, cluster analysis, nonmetric multidimensional scaling, Procrustes, variance partitioning), we …


Importance Considered Organic Versus Inorganic Source Of Carbon To Lakes For Calculating Net Effect On Landscape C Budgets, Weiqi Lu, Shilu Wang, Kevin M. Yeager, Fang Liu, Qiangsheng Huang, Yuxue Yang, Peng Xiang, Yingchun Lü, Chong-Qiang Liu Apr 2018

Importance Considered Organic Versus Inorganic Source Of Carbon To Lakes For Calculating Net Effect On Landscape C Budgets, Weiqi Lu, Shilu Wang, Kevin M. Yeager, Fang Liu, Qiangsheng Huang, Yuxue Yang, Peng Xiang, Yingchun Lü, Chong-Qiang Liu

Earth and Environmental Sciences Faculty Publications

Lakes and reservoirs transform, emit, and bury carbon that is exported from land and are thus significant components of terrestrial carbon budgets. Their significance is often assessed by integrating these water bodies into terrestrial primary production. However, the transfer of inorganic carbon (IC) is likely a sticking point for these integrations because IC is not part of net ecosystem production. Here we integrated carbon evasion and organic carbon (OC) burial in a lake in the context of inorganic and OC cycling in a karst catchment from a system perspective. The lake emitted carbon dioxide (CO2) and buried OC …


Zircon U-Pb Geochronology Of Two Basement Cores (Kentucky, Usa): Implications For Late Mesoproterozoic Sedimentation And Tectonics In The Eastern Midcontinent, David P. Moecher, J. Richard Bowersox, John B. Hickman Jan 2018

Zircon U-Pb Geochronology Of Two Basement Cores (Kentucky, Usa): Implications For Late Mesoproterozoic Sedimentation And Tectonics In The Eastern Midcontinent, David P. Moecher, J. Richard Bowersox, John B. Hickman

Earth and Environmental Sciences Faculty Publications

Basement cores from two wells drilled west and east of the Grenville front consist of feldspathic litharenite and granitic orthogneiss, respectively. Detrital zircon U-Pb ages for the litharenite define a broad dominant U-Pb age mode at ca. 1115 Ma. The dominant mode matches that for the type locality of the Middle Run Formation in the Ohio subsurface and is interpreted to consist of detrital zircons sourced from East Continent Rift volcanic sources (ca. 1100 Ma) and Grenville Shawinigan granites/gneisses (1120–1180 Ma). The youngest detrital zircon ages (ca. 1020 Ma) require a maximum depositional age that is at least 70 My …


Lcs-1: A High-Resolution Global Model Of The Lithospheric Magnetic Field Derived From Champ And Swarm Satellite Observations, Nils Olsen, Dhananjay Ravat, Christopher C. Finlay, Livia K. Kother Sep 2017

Lcs-1: A High-Resolution Global Model Of The Lithospheric Magnetic Field Derived From Champ And Swarm Satellite Observations, Nils Olsen, Dhananjay Ravat, Christopher C. Finlay, Livia K. Kother

Earth and Environmental Sciences Faculty Publications

We derive a new model, named LCS-1, of Earth’s lithospheric field based on four years (2006 September–2010 September) of magnetic observations taken by the CHAMP satellite at altitudes lower than 350 km, as well as almost three years (2014 April–2016 December) of measurements taken by the two lower Swarm satellites Alpha and Charlie. The model is determined entirely from magnetic ‘gradient’ data (approximated by finite differences): the north–south gradient is approximated by first differences of 15 s along-track data (for CHAMP and each of the two Swarm satellites), while the east–west gradient is approximated by the difference between observations taken …


East African Weathering Dynamics Controlled By Vegetation-Climate Feedbacks, Sarah J. Ivory, Michael M. Mcglue, Geoffrey S. Ellis, Adam Boehlke, Anne-Marie Lézine, Annie Vincens, Andrew S. Cohen Sep 2017

East African Weathering Dynamics Controlled By Vegetation-Climate Feedbacks, Sarah J. Ivory, Michael M. Mcglue, Geoffrey S. Ellis, Adam Boehlke, Anne-Marie Lézine, Annie Vincens, Andrew S. Cohen

Earth and Environmental Sciences Faculty Publications

Tropical weathering has important linkages to global biogeochemistry and landscape evolution in the East African rift. We disentangle the influences of climate and terrestrial vegetation on chemical weathering intensity and erosion at Lake Malawi using a long sediment record. Fossil pollen, microcharcoal, particle size, and mineralogy data affirm that the detrital clays accumulating in deep water within the lake are controlled by feedbacks between climate and hinterland forest composition. Particle-size patterns are also best explained by vegetation, through feedbacks with lake levels, wildfires, and erosion. We develop a new source-to-sink framework that links lacustrine sedimentation to hinterland vegetation in tropical …


Validating A Universal Model Of Particle Transport Lengths With Laboratory Measurements Of Suspended Grain Motions, Robert C. Mahon, Brandon Mcelroy, Suleyman Naqshband May 2017

Validating A Universal Model Of Particle Transport Lengths With Laboratory Measurements Of Suspended Grain Motions, Robert C. Mahon, Brandon Mcelroy, Suleyman Naqshband

Earth and Environmental Sciences Faculty Publications

t The mechanics of sediment transport are of fundamental importance for fluvio-deltaic morphodynamics. The present study focuses on quantifying particle motions and trajectories across a wide range of flow conditions. In particular, a continuous model is presented that predicts particle travel distances for saltation and suspension based on Rouse number and relative grain roughness. By utilizing a series of eight video cameras in a plexiglass flume direct measurements of the distributions of particle travel distances (excursion lengths) were obtained. To this end, experiments were carried out in dark under black lights with fluorescent painted plastic and quartz sand particles. For …


The Fate Of Carbon In Sediments Of The Xingu And Tapajós Clearwater Rivers, Eastern Amazon, Dailson J. Bertassoli Jr., André O. Sawakuchi, Henrique O. Sawakuchi, Fabiano N. Pupim, Gelvam A. Hartmann, Michael M. Mcglue, Cristiano M. Chiessi, Matthias Zabel, Enno Schefuß, Tatiana S. Pereira, Rudney A. Santos, Samantha B. Faustino, Paulo E. Oliveira, Denise C. Bicudo Feb 2017

The Fate Of Carbon In Sediments Of The Xingu And Tapajós Clearwater Rivers, Eastern Amazon, Dailson J. Bertassoli Jr., André O. Sawakuchi, Henrique O. Sawakuchi, Fabiano N. Pupim, Gelvam A. Hartmann, Michael M. Mcglue, Cristiano M. Chiessi, Matthias Zabel, Enno Schefuß, Tatiana S. Pereira, Rudney A. Santos, Samantha B. Faustino, Paulo E. Oliveira, Denise C. Bicudo

Earth and Environmental Sciences Faculty Publications

The Xingu and Tapajós rivers in the eastern Amazon are the largest clearwater systems of the Amazon basin. Both rivers have “fluvial rias” (i.e., lake-like channels) in their downstream reaches as they are naturally impounded by the Amazon mainstem. Fluvial rias are widespread in the Amazon landscape and most of the sedimentary load from the major clearwater and blackwater rivers is deposited in these channels. So far, little is known about the role of Amazon rias as a trap and reactor for organic sediments. In this study, we used organic and inorganic geochemistry, magnetic susceptibility, diatom, and pollen analyses in …


Hydroclimatic Contrasts Over Asian Monsoon Areas And Linkages To Tropical Pacific Ssts, Hai Xu, Jianghu Lan, Enguo Sheng, Bin Liu, Keke Yu, Yuanda Ye, Zhengguo Shi, Peng Cheng, Xulong Wang, Xinying Zhou, Kevin M. Yeager Sep 2016

Hydroclimatic Contrasts Over Asian Monsoon Areas And Linkages To Tropical Pacific Ssts, Hai Xu, Jianghu Lan, Enguo Sheng, Bin Liu, Keke Yu, Yuanda Ye, Zhengguo Shi, Peng Cheng, Xulong Wang, Xinying Zhou, Kevin M. Yeager

Earth and Environmental Sciences Faculty Publications

Knowledge of spatial and temporal hydroclimatic differences is critical in understanding climatic mechanisms. Here we show striking hydroclimatic contrasts between northern and southern parts of the eastern margin of the Tibetan Plateau (ETP), and those between East Asian summer monsoon (EASM) and Indian summer monsoon (ISM) areas during the past ~2,000 years. During the Medieval Period, and the last 100 to 200 years, the southern ETP (S-ETP) area was generally dry (on average), while the northern ETP (N-ETP) area was wet. During the Little Ice Age (LIA), hydroclimate over S-ETP areas was wet, while that over N-ETP area was dry …


The End-Permian Mass Extinction And A Possible Massive Impact, Rebecca Teed May 2016

The End-Permian Mass Extinction And A Possible Massive Impact, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This handout examines the evidence for the theory that a massive meteor impact caused the mass extinction at the end of the Permian Period. This is the worst mass extinction known to geologists, and 90% or more of all species on Earth were wiped out. It is part of a set of four articles on possible causes of the Permian and Cretaceous mass extinctions that can be used to organize classroom debates or to have students compare and contrast the events and their causes.


The End-Cretaceous Mass Extinction And The Deccan Traps Eruptions, Rebecca Teed May 2016

The End-Cretaceous Mass Extinction And The Deccan Traps Eruptions, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This handout focuses on the evidence for the theory that a series of flood-basalt eruptions in northern India caused the mass extinction at the end of the Cretaceous Period. The dinosaurs and about 75% of all marine invertebrate species and many other organisms died abruptly at this time. This is one of a set of four articles on possible causes of the Permian and Cretaceous mass extinctions that can be used to organize classroom debates or to have students compare and contrast the events and their causes.


The End-Cretaceous Mass Extinction And The Chicxulub Impact, Rebecca Teed May 2016

The End-Cretaceous Mass Extinction And The Chicxulub Impact, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This handout focuses on the evidence for the theory that a massive meteor impact off the coast of Mexico caused the mass extinction at the end of the Cretaceous Period. The dinosaurs and about 75% of all marine invertebrate species and many other organisms died abruptly at this time. It is part of a set of four articles on possible causes of the Permian and Cretaceous mass extinctions that can be used to organize classroom debates or to have students compare and contrast the events and their causes.


The End-Permian Mass Extinction And The Siberian Traps Eruptions, Rebecca Teed May 2016

The End-Permian Mass Extinction And The Siberian Traps Eruptions, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This handout focuses on the evidence for the theory that a series of flood-basalt eruptions in Siberia caused the mass extinction at the end of the Permian Period. This is the worst mass extinction known to geologists, and 90% or more of all species on Earth were wiped out. It is part of a set of four articles on possible causes of the Permian and Cretaceous mass extinctions that can be used to organize classroom debates or to have students compare and contrast the events and their causes.


Inverse Modelling Of The Reversely Magnetized, Shallow Plumbing System Hosting Oil Reservoirs Of The Auca Mahuida Volcano (Payeina Retroarc, Neuquén Basin, Argentina), John Paine, Riccardo De Ritis, Guido Ventura, Mariana Longo, Dhananjay Ravat, Fabio Speranza, Massimo Chiappini Dec 2015

Inverse Modelling Of The Reversely Magnetized, Shallow Plumbing System Hosting Oil Reservoirs Of The Auca Mahuida Volcano (Payeina Retroarc, Neuquén Basin, Argentina), John Paine, Riccardo De Ritis, Guido Ventura, Mariana Longo, Dhananjay Ravat, Fabio Speranza, Massimo Chiappini

Earth and Environmental Sciences Faculty Publications

The Auca Mahuida volcano (2.03–0.88 Ma) located east of the Andean thrust front in the Neuquén basin (Argentina) hosts an oil system of thermogenic origin and is affected by the NW–SE striking-faults. Intrusive bodies and the underlying Jurassic sediments constitute the reservoir rocks. Aeromagnetic data collected in the Auca Mahuida area detected multiple dipolar magnetic anomalies, many of which have reverse polarity. Palaeomagnetic measurements on rock samples collected in the field together with available age determinations indicate that the reversely magnetized sources were mainly emplaced during the Matuyama reverse polarity chron while the normal polarity sources were emplaced during the …


The Volta Grande Do Xingu: Reconstruction Of Past Environments And Forecasting Of Future Scenarios Of A Unique Amazonian Fluvial Landscape, A. O. Sawakuchi, G. A. Hartmann, H. O. Sawakuchi, F. N. Pupim, D. J. Bertassoli, M. Parra, J. L. Antinao, L. M. Sousa, M. H. Sabaj Pérez, P. E. Oliveira, R. A. Santos, J. F. Savian, C. H. Grohmann, V. B. Medeiros, Michael M. Mcglue, D. C. Bicudo, S. B. Faustino Dec 2015

The Volta Grande Do Xingu: Reconstruction Of Past Environments And Forecasting Of Future Scenarios Of A Unique Amazonian Fluvial Landscape, A. O. Sawakuchi, G. A. Hartmann, H. O. Sawakuchi, F. N. Pupim, D. J. Bertassoli, M. Parra, J. L. Antinao, L. M. Sousa, M. H. Sabaj Pérez, P. E. Oliveira, R. A. Santos, J. F. Savian, C. H. Grohmann, V. B. Medeiros, Michael M. Mcglue, D. C. Bicudo, S. B. Faustino

Earth and Environmental Sciences Faculty Publications

The Xingu River is a large clearwater river in eastern Amazonia and its downstream sector, known as the Volta Grande do Xingu (“Xingu Great Bend”), is a unique fluvial landscape that plays an important role in the biodiversity, biogeochemistry and prehistoric and historic peopling of Amazonia. The sedimentary dynamics of the Xingu River in the Volta Grande and its downstream sector will be shifted in the next few years due to the construction of dams associated with the Belo Monte hydropower project. Impacts on river biodiversity and carbon cycling are anticipated, especially due to likely changes in sedimentation and riverbed …