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A Four-Legged Megalosaurus And Swimming Brontosaurs, Jordan C. Oldham 2018 Cedarville University

A Four-Legged Megalosaurus And Swimming Brontosaurs, Jordan C. Oldham

Channels: Where Disciplines Meet

Thomas Kuhn in his famous work The Structure of Scientific Revolutions laid out the framework for his theory of how science changes. At the advent of dinosaur paleontology fossil hunters like Gideon Mantell discovered some of the first dinosaurs like Iguanodon and Megalosaurus. Through new disciples like Georges Cuvier’s comparative anatomy lead early dinosaur paleontologist to reconstruct them like giant reptiles of absurd proportions. This lead to the formation of a new paradigm that prehistoric animals like dinosaurs existed and eventually went extinct. The first reconstructions of dinosaur made them to look like giant counterparts of their modern cousins ...


Devonian Stromatoporoid Interactions At The Falls Of The Ohio State Park, Clarksville, Indiana, Morgan Sierra Hall 2018 Bellarmine University

Devonian Stromatoporoid Interactions At The Falls Of The Ohio State Park, Clarksville, Indiana, Morgan Sierra Hall

Undergraduate Theses

Stromatoporoids are calcitic sponges that occurred in the fossil record from the Early Ordovician to Late Devonian period. These sponges interacted with other organisms, especially rugose and tabulate corals. Some corals appear to benefit from the rigidity of stromatoporoids in response to turbulent waters. Stromatoporoids and many corals went extinct during the Frasnian-Famennian crisis when paleoenvironmental parameters were shifting. Studying the relationships between these taxa may provide insight to their vulnerability during the extinction.

This research was performed at the Falls of the Ohio in Clarksville, Indiana. Organisms in the Coral Zone were studied using transect sampling. Each fossil along ...


An Investigation Of Hydrothermal Veins Along The Foy Offset Dyke, Sudbury Impact Structure, Ontario, Sarah Ann CoDyre 2018 The University of Western Ontario

An Investigation Of Hydrothermal Veins Along The Foy Offset Dyke, Sudbury Impact Structure, Ontario, Sarah Ann Codyre

Electronic Thesis and Dissertation Repository

A multi-stage hydrothermal system is related to the 1.85 Ga Sudbury impact structure. This system began in the Sudbury Igneous Complex (SIC) and radiated outward along the offset dykes. Through the combination of orientation measurements of veins in the field, petrography and geochemistry of these veins, this study has determined that there are four types of hydrothermal epidote-quartz veins categorized by their orientation, petrography and geochemistry. This study discovered that there are general trends with increasing distance from the SIC along the Foy Offset Dyke. From this it can be concluded that this is in fact SIC-driven hydrothermal event ...


Predicting Stratigraphic Outcrops Using A Lidar Digital Elevation Model In A Karst Landscape, Fort Hood Military Installation, Texas, Keely Armstrong 2018 Stephen F Austin State University

Predicting Stratigraphic Outcrops Using A Lidar Digital Elevation Model In A Karst Landscape, Fort Hood Military Installation, Texas, Keely Armstrong

Undergraduate Research Conference

The Fort Hood Military Installation is a karst landscape characterized by Cretaceous-age limestone plateaus and canyons in Bell and Coryell counties, Texas. The area is located in the Lampasas Cut Plain region of the Edwards Plateau and is stratigraphically defined by exposures of the Fredericksburg Group, namely the Comanche Peak and Edwards carbonates. The topography is dominated by plateaued draining divides capped by the resistant Edwards limestone and bordered by steep scarps exposing alternating layers of the Comanche Peak and Edwards units. This interfingering relationship has created a variable slope along the edges of the plateaus, defined by lithology.

The ...


Polarimetric Sar As A Tool For Remote Sensing Salt Diapirs, Axel Heiberg Island, Nunavut, Elise M. Harrington 2018 The University of Western Ontario

Polarimetric Sar As A Tool For Remote Sensing Salt Diapirs, Axel Heiberg Island, Nunavut, Elise M. Harrington

Electronic Thesis and Dissertation Repository

The costs and hazards associated with traditional geological mapping have driven rapid advancement of remote predictive mapping techniques using satellite data. However, few studies have implemented synthetic aperture radar for geology. This study uses quad-polarimetric RADARSAT-2 and PALSAR-1 data to produce circular polarization ratio images over Axel Heiberg Island, Nunavut, Canada. These images are used to characterize the radar properties of gypsum and anhydrite diapirs and secondary salt deposits that have been mapped using visible and near infrared, short wave infrared, and thermal infrared spectroscopy. Diapiric salt outcrops appear rough in radar at the C-Band and L-Band (cm-dm) scales, whereas ...


Unusual Internal Structure Of Cm-Sized Coldwater Calcite: Weichselian Spars In Former Pools Of The Zinnbergschacht Cave (Franconian Alb/Se Germany), Detlev K. Richter, Rolf D. Neuser, Martin Harder, Hardy Schabdach, Denis Scholz 2018 Ruhr-Universität Bochum

Unusual Internal Structure Of Cm-Sized Coldwater Calcite: Weichselian Spars In Former Pools Of The Zinnbergschacht Cave (Franconian Alb/Se Germany), Detlev K. Richter, Rolf D. Neuser, Martin Harder, Hardy Schabdach, Denis Scholz

International Journal of Speleology

The investigation of the internal structure of calcite crystals is a new focus in speleothem science, especially in the range of crystallization temperatures close to 0°C. Recently found calcite spars from Zinnbergschacht Cave of the Franconian Alb (SE Germany) are ideal for multi-method investigation. The elongated calcites (up to 6 cm in length) with three to six lateral faces and basal triangular faces at the ends are observed in collapse-zones in the cave. 230Th/U-ages of 38.9 ka suggest formation during the periglacial Weichselian, between the Scandinavian and Alpine Glaciations. The δ18O and δ13 ...


A Hydrologic And Hydraulic Analysis Of Massie’S Creek Gorge, Greene County, Oh, Using Hec-Ras, Joshua W. Perez 2018 Cedarville University

A Hydrologic And Hydraulic Analysis Of Massie’S Creek Gorge, Greene County, Oh, Using Hec-Ras, Joshua W. Perez

The Research and Scholarship Symposium

Massie’s Creek is a small tributary of the Little Miami River, located in southwest Ohio near the village of Cedarville. For approximately 1.5 miles (2.4 km) it flows westward through the Indian Mound Reserve Park, an area which occasionally undergoes flooding. In the first ½ mile (0.8 km) of the park, the stream is confined by a deep gorge, 40 feet (12 m) or more tall, and quickly flattens to a meandering stream through the rest of the park. The present study describes the application of HEC-RAS with the integration of ArcGIS for steady flow analyses ...


Grain Size Analysis Of Massie’S Creek Near Flax Pond And Community Park, Andrew R. Rivera 2018 Cedarville University

Grain Size Analysis Of Massie’S Creek Near Flax Pond And Community Park, Andrew R. Rivera

The Research and Scholarship Symposium

The goal of this research is to better understand the stream bed conditions at the confluence of North Fork and South Fork Massie’s Creek next to Community Park in downtown Cedarville, OH. Stream depth as well as sediment type where determined as a result of field work done for this project. The depth data was then used to create a contour map of the pool behind the low-head dam that defines the lower boundary of the confluence area. Sediment distribution is represented on this map based on laboratory particle size analysis and gross piratical size analysis done in the ...


Replication And Reinsertion Of Stalagmites Sampled For Paleoclimatic Purposes, Eleuterio Baeza, Rafael P. Lozano, Carlos Rossi 2018 Instituto Geológico y Minero de España

Replication And Reinsertion Of Stalagmites Sampled For Paleoclimatic Purposes, Eleuterio Baeza, Rafael P. Lozano, Carlos Rossi

International Journal of Speleology

Sampling stalagmites for paleoclimatic study can enter into conflict with preserving the beauty and integrity of caves. To minimize this impact, a variety of sampling strategies have been used by researches aware of cave-conservation issues. Based on our experience in two caves (El Soplao and La Buenita, Cantabria, N Spain), we propose to apply molding and casting laboratory techniques to create replicas of stalagmites, placing the replicas back in the original cave locations so that the impact of sampling to the cave is severely reduced. We provide detailed descriptions of the molding and casting methods, which vary depending on stalagmite ...


Regional Stress Regime Study Of East Texas Based On Orientation Of Fractures In The Weches Formation, Cory D. Ellison 2018 Stephen F Austin State University

Regional Stress Regime Study Of East Texas Based On Orientation Of Fractures In The Weches Formation, Cory D. Ellison

Electronic Theses and Dissertations

Fractures in the Weches Formation in a roughly 50 mile radius around Nacogdoches, Texas were documented and analyzed using data obtained at various outcrops. This data was used to infer information about the regional stress regime based on the direction of maximum/minimum horizontal stresses (SHmax / SHmin) that formed the fractures. This is based on the principle that systematic, steeply dipping, mode I joints propagate in the direction of SHmax and normal to the direction of SHmin. Joints in the Weches Formation are typically iron filled and are predominantly opening mode, indicated by crack-seal formation, steep dip (700 – 900) and ...


Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal 2018 University of Nebraska - Lincoln

Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal

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Updated April 2018


Conflicting Theories: Impact And Volcanism, Dimitrik Johnson 2018 Germanna Community College

Conflicting Theories: Impact And Volcanism, Dimitrik Johnson

Student Writing

The K-Pg extinction (or K-T extinction), more commonly referred to as the extinction of the dinosaurs, is the most recent mass extinction event in Earth’s history. The causes of the event have been widely debated, with the two main theories being a large asteroid impact or volcanism. While some scientists disagree, the most popular and agreed upon theory is that a large asteroid impacted Earth 65 million years ago, creating a toxic dust cloud that filled the atmosphere, and resulted in the eventual extinction of most of the dinosaurs. This theory was first brought to life by Luis Alvarez ...


Mapping And Interpreting The Glacial Geology Of Pictured Rocks National Lakeshore, Michigan, Sarah M. VanderMeer 2018 Western Michigan University

Mapping And Interpreting The Glacial Geology Of Pictured Rocks National Lakeshore, Michigan, Sarah M. Vandermeer

Dissertations

Pictured Rocks National Lakeshore is among the most popular parks in Michigan, yet prior to this study, it was the only National Park that lacked a detailed surficial geology map characterizing the distribution of sediments and landforms. Additionally, much of the landscape remained unexplored. These factors prevented thorough interpretations of landscape development and evolution. This research aims to map and further explore the relationship of glacial sediments and landforms throughout Pictured Rocks to refine and expand the current understanding of glacial events that shaped this landscape.

A new, detailed (1:24,000-scale) surficial geology map of the ten 7.5-minute ...


A Geomorphological Study Of Yardangs In China, The Altiplano/Puna Of Argentina, And Iran As Analogs For Yardangs On Titan, Dustin Shawn Northrup 2018 Brigham Young University

A Geomorphological Study Of Yardangs In China, The Altiplano/Puna Of Argentina, And Iran As Analogs For Yardangs On Titan, Dustin Shawn Northrup

All Theses and Dissertations

Collections of straight, RADAR-bright, linear features, or BLFs, on Saturn's moon Titan are revealed in Cassini SAR (Synthetic Aperture RADAR) images. Most are widely distributed across the northern midlatitudes SAR on SAR swaths T18, T23, T30, T64, and T83 and in swath T56 in the southern midlatitudes. To understand the origin of these features, we compare them with terrestrial yardangs in Dunhuang, China, the Altiplano/Puna of Argentina, and the Lut Desert of Iran and with a similar morphological landform, linear dunes in the Namib Sand Sea, Namibia and on Titan. We apply a statistical classification model developed through ...


A Geophysical And Geological Analysis Of A Regressive-Phase Lake Bonneville Deposit, Pilot Valley, Nv, Katelynn Marie Smith 2018 Brigham Young University

A Geophysical And Geological Analysis Of A Regressive-Phase Lake Bonneville Deposit, Pilot Valley, Nv, Katelynn Marie Smith

All Theses and Dissertations

Pilot Valley, located in the eastern Basin and Range, north of Wendover, UT, contains numerous shorelines and depositional remnants of late Pleistocene Lake Bonneville. These remnants present classic ground penetrating radar (GPR) targets due to their coherent stratification, low clay, low salinity, and low moisture content. Three-dimensional (3D) GPR imaging can resolve fine-scale stratigraphy of these deposits down to a few centimeters. While lake levels fluctuated due to flooding events, climatic changes were the dominant factor in controlling lake levels. In Pilot Valley, the paleowind entered from the northwest, with storms coming from the south, and circulated clockwise around the ...


Vertical Sediment Accretion In Jamaica Bay Wetlands, New York, Ryan Christopher Clarke 2018 Louisiana State University and Agricultural and Mechanical College

Vertical Sediment Accretion In Jamaica Bay Wetlands, New York, Ryan Christopher Clarke

LSU Master's Theses

Over the last century, ~60% of the saltmarsh wetlands in Jamaica Bay (in the Gateway National Recreation Area of the Greater New York City region) have been converted to intertidal or subtidal unvegetated mudflats and projections suggest that all of Jamaica Bay’s saltmarsh wetlands may disappear within the next two decades. After landfall of Hurricane Sandy in 2012 and to better understand environmental controls on the maintenance of the remaining Jamaica Bay wetlands, cores were collected from twelve saltmarsh locations in the bay to study the chronology of wetland vertical accretion and mineral sediment accumulation. In association with the ...


Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna 2018 Wesleyan University

Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna

Melissa Luna

No abstract provided.


Study On The Surface Features Of Preg-Robbing Carbonaceous Matter During Oxidation Treatment, Mana Pourdasht 2018 The University of Western Ontario

Study On The Surface Features Of Preg-Robbing Carbonaceous Matter During Oxidation Treatment, Mana Pourdasht

Electronic Thesis and Dissertation Repository

Carbonaceous gold ores have the ability to adsorb gold (I) cyanide from leach solutions during processing. This phenomenon, known as preg-robbing, is responsible for poor recoveries as the carbonaceous materials of the ore compete with activated carbon used during the leaching and adsorption phase of processing. Chemical oxidation of carbonaceous materials by different reagents has been utilized to investigate and compare the mechanism of Au (CN)2 adsorption onto carbonaceous materials prior to and following the treatment.

The procedure for characterization of the carbonaceous materials (plain and modified) in the sample combines the use of several analytical techniques and test ...


Humans Thrived In South Africa Through The Toba Eruption About 74,000 Years Ago, Eugene I. Smith, Zenobia Jacobs, Racheal Johnsen, Minghua Ren, Erich C. Fisher, Simen Oestmo, Jayne Wilkins, Jacob A. Harris, Panagiotis Karkanas, Shelby Fitch, Amber Ciravolo, Deborah Keenan, Naomi Cleghorn, Christine S. Lane, Thalassa Matthews, Curtis W. Marean 2018 University of Nevada, Las Vegas

Humans Thrived In South Africa Through The Toba Eruption About 74,000 Years Ago, Eugene I. Smith, Zenobia Jacobs, Racheal Johnsen, Minghua Ren, Erich C. Fisher, Simen Oestmo, Jayne Wilkins, Jacob A. Harris, Panagiotis Karkanas, Shelby Fitch, Amber Ciravolo, Deborah Keenan, Naomi Cleghorn, Christine S. Lane, Thalassa Matthews, Curtis W. Marean

Geoscience Faculty Publications

Approximately 74 thousand years ago (ka), the Toba caldera erupted in Sumatra. Since the magnitude of this eruption was first established, its effects on climate, environment and humans have been debated1. Here we describe the discovery of microscopic glass shards characteristic of the Youngest Toba Tuff—ashfall from the Toba eruption—in two archaeological sites on the south coast of South Africa, a region in which there is evidence for early human behavioural complexity. An independently derived dating model supports a date of approximately 74 ka for the sediments containing the Youngest Toba Tuff glass shards. By defining the input ...


Fire-Induced Mineralogical Changes In Midwest Tallgrass Prairie Soils, Lacey LeGrand 2018 University of Nebraska at Omaha

Fire-Induced Mineralogical Changes In Midwest Tallgrass Prairie Soils, Lacey Legrand

Student Research and Creative Activity Fair

Tallgrass prairies are productive ecosystems that historically covered a large part of the Midwest and in the past were subjected to frequent, natural fire regimes. Today prairie remnants are often managed by ecological burns. Glacier Creek Preserve is a restored prairie in Omaha, Nebraska that includes randomized research plots established in 1978 to study the effects of burning on vegetation and provides a controlled field environment to investigate the effects of fire on soils. The purpose of this study is to compare soil mineralogy in long-term burned and unburned plots to answer the question: “Does prescribed burning induce mineralogical changes ...


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