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The Geologic Times, Vol. 1, Sara Mana 2019 Salem State University

The Geologic Times, Vol. 1, Sara Mana

Earth Science Association

The debut issue of the Earth Science Association's newsletter, The Geologic Times.

Contents:

The Evolution of Theropod Hands as seen in a Newly Described Italian Dinosaur by Marcello Toscanini

Plate Tectonics Crossword Puzzle

Is the Great Salt Lake dying? by Alyssa B. Cassias

Structural Geology @SSU - The Story of Rafes Chasm in Magnolia, MA by Eleanor Roccio

Mineral of the Month: Tourmaline! by Klementina Mato

ESA News


Age And Pattern Of The Southern High-Latitude Continental End-Permian Extinction Constrained By Multiproxy Analysis, Christopher R. Fielding, Tracy D. Frank, Stephen McLoughlin, Vivi Vajda, Chris Mays, Allen P. Tevyaw, Arne Winguth, Cornelia Winguth, Robert S. Nicoll, Malcom Bocking, James L. Crowley 2019 University of Nebraska-Lincoln

Age And Pattern Of The Southern High-Latitude Continental End-Permian Extinction Constrained By Multiproxy Analysis, Christopher R. Fielding, Tracy D. Frank, Stephen Mcloughlin, Vivi Vajda, Chris Mays, Allen P. Tevyaw, Arne Winguth, Cornelia Winguth, Robert S. Nicoll, Malcom Bocking, James L. Crowley

Papers in the Earth and Atmospheric Sciences

Past studies of the end-Permian extinction (EPE), the largest biotic crisis of the Phanerozoic, have not resolved the timing of events in southern high-latitudes. Here we use palynology coupled with high-precision CA-ID-TIMS dating of euhedral zircons from continental sequences of the Sydney Basin, Australia, to show that the collapse of the austral Permian Glossopteris flora occurred prior to 252.3 Ma (~370 kyrs before the main marine extinction). Weathering proxies indicate that floristic changes occurred during a brief climate perturbation in a regional alluvial landscape that otherwise experienced insubstantial change in fluvial style, insignificant reorganization of the depositional surface, and ...


Age And Pattern Of The Southern High-Latitude Continental End-Permian Extinction Constrained By Multiproxy Analysis, Christopher R. Fielding, Tracy D. Frank, Stephen McLoughlin, Vivi Vajda, Chris Mays, Allen P. Tevyaw, Arne Winguth, Cornelia Winguth, Robert S. Nicoll, Malcolm Bocking, James L. Crowley 2019 University of Nebraska-Lincoln

Age And Pattern Of The Southern High-Latitude Continental End-Permian Extinction Constrained By Multiproxy Analysis, Christopher R. Fielding, Tracy D. Frank, Stephen Mcloughlin, Vivi Vajda, Chris Mays, Allen P. Tevyaw, Arne Winguth, Cornelia Winguth, Robert S. Nicoll, Malcolm Bocking, James L. Crowley

Papers in the Earth and Atmospheric Sciences

Past studies of the end-Permian extinction (EPE), the largest biotic crisis of the Phanerozoic, have not resolved the timing of events in southern high-latitudes. Here we use palynology coupled with high-precision CA-ID-TIMS dating of euhedral zircons from continental sequences of the Sydney Basin, Australia, to show that the collapse of the austral Permian Glossopteris flora occurred prior to 252.3 Ma (~370 kyrs before the main marine extinction). Weathering proxies indicate that floristic changes occurred during a brief climate perturbation in a regional alluvial landscape that otherwise experienced insubstantial change in fluvial style, insignificant reorganization of the depositional surface, and ...


Probability Of Streamflow Permanence Model (Prosper): A Spatially Continuous Model Of Annual Streamflow Permanence Throughout The Pacific Northwest, K. E. Kaiser 2019 Boise State University

Probability Of Streamflow Permanence Model (Prosper): A Spatially Continuous Model Of Annual Streamflow Permanence Throughout The Pacific Northwest, K. E. Kaiser

Geosciences Faculty Publications and Presentations

The U.S. Geological Survey (USGS) has developed the PRObability of Streamflow PERmanence (PROSPER) model, a GIS raster-based empirical model that provides streamflow permanence probabilities (probabilistic predictions) of a stream channel having year-round flow for any unregulated and minimallyimpaired stream channel in the Pacific Northwest region, U.S. The model provides annual predictions for 2004–2016 at a 30-m spatial resolution based on monthly or annually updated values of climatic conditions and static physiographic variables associated with the upstream basin. Predictions correspond to any pixel on the channel network consistent with the medium resolution National Hydrography Dataset channel network stream ...


Hydrological Drivers Of Carbon Dioxide Cycling From Headwaters To The Coastal Ocean On A Tropical Island, Paul A. Macklin 2019 Southern Cross University

Hydrological Drivers Of Carbon Dioxide Cycling From Headwaters To The Coastal Ocean On A Tropical Island, Paul A. Macklin

Theses

This thesis investigates the hydrological drivers of carbon dioxide cycling from mountain headwaters to the coastal ocean in modified and unmodified systems on a tropical island (Bali, Indonesia). The central hypothesis is that a combination of rainfall and groundwater seepage drive aquatic CO2 fluxes. Chapter 1 provides a general review of the topic. Chapter 2 examines atmospheric CO2 fluxes in a reservoir and a tropical volcanic lake. The highest pCO2 occurred in the wet season in both systems. In the natural lake, the metabolism of surface water was an important driver of CO2 dynamics, while ...


Mycorrhizal Colonization And Its Relationship With Plant Performance Differs Between Exotic And Native Grassland Plant Species, Aleksandra Checinska Sielaff, H. Wayne Polley, Andres Fuentes-Ramirez, Kirsten Hofmockel, Brian J. Wilsey 2019 Iowa State University

Mycorrhizal Colonization And Its Relationship With Plant Performance Differs Between Exotic And Native Grassland Plant Species, Aleksandra Checinska Sielaff, H. Wayne Polley, Andres Fuentes-Ramirez, Kirsten Hofmockel, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

Many grasslands have been transformed by exotic species with potentially novel ecological interactions. We hypothesized that exotic and native plant species differ, on average, in their percentage mycorrhizal colonization, and that mycorrhizal colonization is positively related to plant performance in the field. We compared colonization by arbuscular mycorrhizae (AM) fungi in perennial native and exotic species that were paired phylogenetically and by functional groups and grown under a common environment in field plots in Central Texas, USA. Roots were collected from plants in monoculture plots, stained, and percent colonization was assessed with a microscope. Aboveground biomass and dominance in mixture ...


Chaco Canyon, New Mexico: A Caretaker City And A Pilgrimage Destination, Larry Benson, Deanna N. Grimstead, John R. Stein, David A. Roth, Terry I. Plowman 2019 University of Colorado at Boulder

Chaco Canyon, New Mexico: A Caretaker City And A Pilgrimage Destination, Larry Benson, Deanna N. Grimstead, John R. Stein, David A. Roth, Terry I. Plowman

USGS Staff -- Published Research

Some Southwestern archaeologists continue to ascribe to the hypothesis that Chaco was agriculturally productive to the point that it could support at least a few thousand full-time residents. This paper suggests an alternative hypothesis; i.e., Chaco was marginally productive and could only support a few hundred permanent residents. Isotopic analysis of mammal teeth found in trenches cut through platform mounds fronting Pueblo Bonito indicate the possibility that much of the meat consumed by Chacoan residents and visitors came from higher elevation sites bordering the San Juan Basin. We suggest that resident population estimates based on great house room numbers ...


Leaf Nutrients, Not Specific Leaf Area, Are Consistent Indicators Of Elevated Nutrient Inputs, Jennifer Firn, Kimberly J. La Pierre, Lori Biederman, et al. 2019 Queensland University of Technology

Leaf Nutrients, Not Specific Leaf Area, Are Consistent Indicators Of Elevated Nutrient Inputs, Jennifer Firn, Kimberly J. La Pierre, Lori Biederman, Et Al.

Ecology, Evolution and Organismal Biology Publications

Leaf traits are frequently measured in ecology to provide a ‘common currency’ for predicting how anthropogenic pressures impact ecosystem function. Here, we test whether leaf traits consistently respond to experimental treatments across 27 globally distributed grassland sites across 4 continents. We find that specific leaf area (leaf area per unit mass)—a commonly measured morphological trait inferring shifts between plant growth strategies—did not respond to up to four years of soil nutrient additions. Leaf nitrogen, phosphorus and potassium concentrations increased in response to the addition of each respective soil nutrient. We found few significant changes in leaf traits when ...


Modeling The Effects Of Climate Variability On Hydrology And Stream Temperatures In The North Fork Of The Stillaguamish River, Kyra Freeman 2019 Western Washington University

Modeling The Effects Of Climate Variability On Hydrology And Stream Temperatures In The North Fork Of The Stillaguamish River, Kyra Freeman

WWU Graduate School Collection

The Stillaguamish River in northwest Washington State, USA, provides water resources to local agriculture, industry and First Nations Tribes, and provides crucial habitat for several endangered species of salmonids. The watershed experiences a mild maritime climate and high relief, with rain and snowmelt dominating the streamflow. In anticipation of shifts in snowpack, streamflow, and stream temperature, I use projected global climate scenarios and numerical models to examine future climatic variability on streamflow and stream temperatures in the snow-melt dominated North Fork of the Stillaguamish River. I calibrated the physically based Distributed Hydrology Soil Vegetation Model (DHSVM) and River Basin Model ...


A Geological History Of Clark County, Arkansas, Joe Jeffers 2019 Ouachita Baptist University

A Geological History Of Clark County, Arkansas, Joe Jeffers

Articles

The geological history of Clark County is described ranging from 500 million years ago to the present. One-third of present-day Clark County is in the Ouachita Mountains, two-thirds is in the Coastal Plain. The formation of the Ouachita Mountains is described, as is the cretaceous formations that led to biological fossils. Historic mining of minerals is also discussed. For the more technically inclined, a detailed description of the geological formations of the county is included near the end.


Insar Simulations For Swot And Dual Frequency Processing For Topographic Measurements, Gerard Masalias Huguet 2019 University of Massachusetts Amherst

Insar Simulations For Swot And Dual Frequency Processing For Topographic Measurements, Gerard Masalias Huguet

Masters Theses

In Earth remote sensing precise characterization of the backscatter coefficient is important to extract valuable information about the observed target. A system that eliminates platform motion during near-nadir airborne observations is presented in this thesis, showing an improvement on the accuracy of measurements for a Ka- band scatterometer previously developed at Microwave Remote Sensing Laboratory (MIRSL). These very same results are used to simulate the reflectivity of such targets as seen from a spaceborne radar and estimate height errors based on mission-specific geometry. Finally, data collected from a dual-frequency airborne interferometer com- prised by the Ka-band system and an S-band ...


Florida Science: The Science That Makes Florida Different, Terence W. Cavanaugh 2019 University of North Florida

Florida Science: The Science That Makes Florida Different, Terence W. Cavanaugh

Secondary Level Resources

This book was created to assist students with their understanding of how science occurs in Florida. When teaching science or any subject it’s important to remember to begin with the concrete and then move to the abstract. I have found that it has helped my students when I begin by teaching science concepts in a concrete manner and expand from there. For example, when I taught about topographic maps, the students were much more successful in their learning when I started with local topographic maps that included the school and the surrounding area than with places that had mountains ...


Process Units River Evaluation (Pure) Method For River Corridor Delineation, John D. Gartner, Christine E. Hatch 2019 University of Massachusetts Amherst

Process Units River Evaluation (Pure) Method For River Corridor Delineation, John D. Gartner, Christine E. Hatch

Water Reports

River corridors are defined as areas adjacent to rivers that are likely to affect and be affected by river and floodplain processes. Geomorphic and hydrologic models can be used to delineate river corridors to address fundamental questions, such as which parts of the fluvial landscape are most likely to respond to climate and land-use change. Land managers are also increasingly using river corridors for applied purposes such as hazard avoidance, ecological conservation, and water quality protection. Currently, the most-used river corridor delineation methods rely on historic maps, field surveys, and/or calibrated empirical models which may be time-intensive, subjective, or ...


Biogeochemical And Hydrological Impacts Of A Low-Severity Wildfire In The Wetland-Dominated Zone Of Discontinuous Permafrost, Caren J. Ackley 2019 Wilfrid Laurier University

Biogeochemical And Hydrological Impacts Of A Low-Severity Wildfire In The Wetland-Dominated Zone Of Discontinuous Permafrost, Caren J. Ackley

Theses and Dissertations (Comprehensive)

Northern regions are experiencing rapid climate warming. As these regions warm, the occurrences of naturally ignited wildfires are increasing in frequency, severity and area burned, calling for a more thorough understanding of post-fire eco-hydrological impacts. Changes in runoff chemistry, and soil moisture and thermal regimes, have been attributed to the significant loss of organic matter (OM) and exposure of deeper soils, leading to enhanced permafrost degradation, ground surface subsidence and the conversion of peat landscapes from long-term C sinks to sources. However, low-severity wildfires often result in minor OM loss. Due to the significant and immediate threats posed to the ...


High Resolution Spatial Variability In Spring Snowmelt For An Arctic Shrub-Tundra Watershed, Branden J. Walker, Philip Marsh Dr 2019 Wilfrid Laurier University

High Resolution Spatial Variability In Spring Snowmelt For An Arctic Shrub-Tundra Watershed, Branden J. Walker, Philip Marsh Dr

Theses and Dissertations (Comprehensive)

Arctic tundra environments are characterized by spatially heterogeneous end-of-winter snow cover because of high winds that erode, transport and deposit snow over the winter. This spatially variable end-of-winter snow cover subsequently influences the spatial and temporal variability of snowmelt and results in a patchy snowcover over the melt period. Documenting changes in both snow cover area (SCA) and snow water equivalent (SWE) during the spring melt is essential for understanding hydrological systems, but the lack of high-resolution SCA and SWE datasets that accurately capture micro-scale changes are not commonly available, and do not exist for the Canadian Arctic. This study ...


Using Paleolimnology To Establish Baseline Conditions For Metal Contaminants In Advance Of Proposed Mining To Inform A Northern Community-Led Aquatic Monitoring Program, Tłı̨Chǫ Lands, Northwest Territories, Canada., James Telford 2019 Wilfrid Laurier University

Using Paleolimnology To Establish Baseline Conditions For Metal Contaminants In Advance Of Proposed Mining To Inform A Northern Community-Led Aquatic Monitoring Program, Tłı̨Chǫ Lands, Northwest Territories, Canada., James Telford

Theses and Dissertations (Comprehensive)

The Marian Watershed Stewardship Program (MWSP), a community-driven aquatic ecosystem monitoring program, was developed by the Tłı̨chǫ Government to address concerns regarding the cumulative impacts of multiple potential stressors. In particular, the MWSP aims to develop methods that will be effective for detecting potential pollution from the proposed cobalt-gold-copper-bismuth NICO mine within Tłı̨chǫ Lands. In collaboration with the MWSP, paleolimnological methods and geochemical normalization are used to establish pre-mine baselines of lake sediment metals concentrations in the Marian River watershed prior to mine development. This baseline framework can be used to assess for pollution from surficial sediment once ...


Refining The Onset Timing And Slip History Along The Northern Part Of The Teton Fault, Rachel Montague Hoar 2019 University of Kentucky

Refining The Onset Timing And Slip History Along The Northern Part Of The Teton Fault, Rachel Montague Hoar

Theses and Dissertations--Earth and Environmental Sciences

A new apatite (U-Th)/He (AHe) dataset from subvertical transects collected in the Teton and Gallatin Ranges in the Teton-Yellowstone region provides insight for the slip history and length of the Teton fault. Along the northernmost segment of the Teton fault, inverse thermal history modeling of AHe data from Eagles Rest Peak yield a ~9 Ma age for onset of fault slip. This age supports previous interpretations that Mount Moran may be the true center of the Teton fault. This refined interpretation coupled with lengthdisplacement fault scaling analysis and previous estimates of total fault displacement (~6 km) indicates that the ...


Fault Evolution In The Northwest Little San Bernardino Mountains, Southern California: A Reflection Of Tectonic Linkage Between The San Andreas Fault And The Eastern California Shear Zone, Ann Hislop 2019 University of Kentucky

Fault Evolution In The Northwest Little San Bernardino Mountains, Southern California: A Reflection Of Tectonic Linkage Between The San Andreas Fault And The Eastern California Shear Zone, Ann Hislop

Theses and Dissertations--Earth and Environmental Sciences

The Little San Bernardino Mountains (LSBM) Fault Set are N-S dextral faults, east of the restraining bend of the San Andreas Fault (SAF) in southern California, that may form a tectonic linkage between the SAF and the Eastern California Shear Zone. The NW LSBM are a complexly deformed structural domain characterized by the young N-S dextral faults and older NW-oriented Dillon Shear Zone faults. Before the 1992 Joshua Tree (Mw 6.1) and Landers (Mw 7.3) earthquakes, the rugged NW LSBM was the subject of few geologic studies. This bedrock mapping study has further delineated the geometry ...


Phosgene In The Upper Troposphere And Lower Stratosphere: A Marker For Product Gas Injection Due To Chlorine-Containing Very Short Lived Substances, Jeremy J. Harrison, Martyn P. Chipperfield, Ryan Hossaini, Christopher D. Boone, Sandip Dhomse, Wuhu Feng, Peter F. Bernath 2019 Old Dominion University

Phosgene In The Upper Troposphere And Lower Stratosphere: A Marker For Product Gas Injection Due To Chlorine-Containing Very Short Lived Substances, Jeremy J. Harrison, Martyn P. Chipperfield, Ryan Hossaini, Christopher D. Boone, Sandip Dhomse, Wuhu Feng, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Abstract: Phosgene in the atmosphere is produced via the degradation of carbon tetrachloride, methyl chloroform, and a number of chlorine‐containing very short lived substances (VSLS). These VSLS are not regulated by the Montreal Protocol even though they contribute to stratospheric ozone depletion. While observations of VSLS can quantify direct stratospheric source gas injection, observations of phosgene in the upper troposphere/lower stratosphere can be used as a marker of product gas injection of chlorine‐containing VSLS. In this work we report upper troposphere/lower stratosphere measurements of phosgene made by the ACE‐FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer ...


Umsl Faculty Expertise, 2018 Selected Works

Umsl Faculty Expertise

Michael Fix

Research Specializations:
Dinosaurs
General Geology
Paleontology
Volcanoes


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