Academy of Natural Sciences of Philadelphia
Wesleyan University
University of Colorado, Boulder
Biological Sciences
University of Tennessee - Knoxville
First Major Appearance Of Brachiopod-Dominated Benthic Shelly Communities In The Reef Ecosystem During The Early Silurian,
2016
The University of Western Ontario
First Major Appearance Of Brachiopod-Dominated Benthic Shelly Communities In The Reef Ecosystem During The Early Silurian, Cale A.C. Gushulak
Electronic Thesis and Dissertation Repository
The early Silurian reefs of the Attawapiskat Formation in the Hudson Bay Basin preserved the oldest record of major invasion of the coral-stromatoporoid skeletal reefs by brachiopods and other marine shelly benthos, providing an excellent opportunity for studying the early evolution, functional morphology, and community organization of the rich and diverse reef-dwelling brachiopods. Biometric and multivariate analysis demonstrate that the reef-dwelling Pentameroides septentrionalis evolved from the level-bottom-dwelling Pentameroides subrectus to develop a larger and more globular shell. The reef-dwelling brachiopods in the paleoequatorial Hudson Bay Basin were more diverse than contemporaneous higher latitude reef-dwelling brachiopod faunas, with ten distinct community ...
Santonian—Campanian Calcareous Nannofossil Paleobiogeography,
2016
University of Nebraska - Lincoln
Santonian—Campanian Calcareous Nannofossil Paleobiogeography, Brandi R. Moore
Dissertations & Theses in Earth and Atmospheric Sciences
Calcareous nannofossil abundance data from 11 DSDP/ODP sites were analyzed by multivariate methods to assess the paleoceanographic change that is associated with the Santonian-Campanian boundary transition. Data were divided into Santonian or Campanian age groups based on the presence or absence of the lower Campanian nannofossil species, Aspidolithus parcus parcus. All assemblages are dominated by Watznaueria barnesiae, Micula decussata, and Prediscosphaera intercisa. Analyses determined that the relative abundance of M. decussata generally reflects a change in temperature, with a preference for cool water. Prediscosphaera intercisa appears to have had an inverse abundance relationship with M. decussata, suggesting that P ...
Reconstructing The Paleoecology And Biogeography Of Rhinoceroses (Mammalia: Rhinocerotidae) In The Great Plains Of North America, Leading Up To Their Extinction In The Early Pliocene,
2016
University of Nebraska-Lincoln
Reconstructing The Paleoecology And Biogeography Of Rhinoceroses (Mammalia: Rhinocerotidae) In The Great Plains Of North America, Leading Up To Their Extinction In The Early Pliocene, Bian Wang
Dissertations & Theses in Earth and Atmospheric Sciences
Members of the family Rhinocerotidae first appeared in the middle Eocene and were one of most successful mammal groups of the Oligocene and Miocene in North America. Their extinction in the early Pliocene has been attributed to several causes, including cooling climate, an expansion of C4 grasslands, and faunal turnover favoring high-crowned, open habitat-adapted mammalian taxa. This study tests whether the extinction of North American rhinoceroses in the Great Plains was abrupt or gradual by examining changes in their paleogeographic distribution in a series of time-slices through the Barstovian, Clarendonian, and Hemphillian North American land-mammal ages. It further examines ...
Shell Bluff – A Fossiliferous Ridge, The Site Of The Extinct Oyster Crassostrea Gigantissima And History Of Its Identification,
2016
Bartram Trail Conference
Shell Bluff – A Fossiliferous Ridge, The Site Of The Extinct Oyster Crassostrea Gigantissima And History Of Its Identification, Elliott O. Edwards Jr.
Georgia Journal of Science
Shell Bluff is described by geologists as stratigraphically one of the most important exposures in the Georgia Coastal Plain because the bluff is home to the large oyster, Crassostrea gigantissima, now extinct. Native Americans inhabited this area prior to Hernando DeSoto and his men who visited the area in 1540. They were probably the first Europeans to visit Shell Bluff. John and son William Bartram visited the bluff in 1764 and John described the bluff in his journal and the existence of large oysters. The British naturalist, John Finch, described a fossil oyster taken from the site in 1824 as ...
Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma,
2016
Stephen F Austin State University
Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres
Electronic Theses and Dissertations
Cone in cone concretions found in the Stanley Group of Southeastern Oklahoma have a variety of external and internal attributes which allow diagenetic and theoretical models of formation to be hypothesized. Stanley Group carbonate cone in cone concretions are initially formed in sulfur reducing horizons at shallow burial depths in a poorly circulated possibly deep trough containing siliceous sediments and organic matter. Collected concretions near the town of Smithville, Oklahoma displayed four different external morphologies and four variations of mineral constituents. All concretions contained microscopic cones which initiated diffusion and/or fluid patterns and is an early cementation process that ...
The Stratigraphic Position Of Fossil Vertebrates From The Pojoaque Member Of The Tesuque Formation (Middle Miocene, Late Barstovian) Near Española, New Mexico,
2016
Stephen F. Austin State University
The Stratigraphic Position Of Fossil Vertebrates From The Pojoaque Member Of The Tesuque Formation (Middle Miocene, Late Barstovian) Near Española, New Mexico, Garrett R. Williamson
Electronic Theses and Dissertations
The stratigraphy of the Pojoaque Member of the Tesuque Formation near Española, NM is not well understood. This region, during the Middle Miocene, represented a dynamic alluvial fan-fluvial-lacustrine environment within the Española Basin while the Rio Grande Rift was active. Cavazza (1986) identified two paleodrainage systems (lithosome A, basin-margin facies and B, basin-floor facies) by means of sandstone and conglomerate petrology, paleocurrent, and sedimentary facies analyses. After x-ray diffraction analyses of claystones within lithosome B, mordenite was discovered, which is a zeolite mineral commonly found within volcanic rocks. This is significant because the presence of mordenite confirms Cavazza’s (1986 ...
The End-Cretaceous Mass Extinction And The Chicxulub Impact,
2016
Wright State University - Main Campus
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-Cretaceous Mass Extinction And The Deccan Traps Eruptions,
2016
Wright State University - Main Campus
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-Permian Mass Extinction And A Possible Massive Impact,
2016
Wright State University - Main Campus
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-Permian Mass Extinction And The Siberian Traps Eruptions,
2016
Wright State University - Main Campus
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.
Constraining Neogene Temperature And Precipitation Histories In The Central Great Plains Using The Fossil Record Of Alligator,
2016
University of Nebraska-Lincoln
Constraining Neogene Temperature And Precipitation Histories In The Central Great Plains Using The Fossil Record Of Alligator, Evan Whiting
Dissertations & Theses in Earth and Atmospheric Sciences
Most amphibians and reptiles (excluding birds) are poikilothermic; their internal body temperature varies with that of their external environment. This makes them useful as climate proxies, especially when linked to geographic distributions of ambient climate. I evaluate the utility of the extant crocodylian genus Alligator as a paleoclimate proxy for the Central Great Plains (CGP) using species distribution modeling. Alligator is a readily identifiable taxon with a good CGP fossil record during the Neogene (~23–2.6 Ma). Alligator first appeared in the CGP in the late Eocene (~37 Ma), was absent during most of the Oligocene, reappeared in the ...
Microstructures Produced By Hadrosaur Bones From Alaska And Wyoming,
2016
Cedarville University
Microstructures Produced By Hadrosaur Bones From Alaska And Wyoming, Mark P. Guilliams, Samantha J. Lefaive, Michael D. Sprague
The Research and Scholarship Symposium
Since 2005 when Dr. Mary Schweitzer made the first discovery, microstructures with the appearance of “osteocytes” and “blood vessels” have been recovered from fossils of various localities, dating back as far as the Triassic. The majority of these finds have come from dense, cortical bone but recently have been discovered in cancellous bone. Since her initial discovery, Schweitzer has done a lot of work to verify that these microstructures are not biofilms, but instead are original organic tissue. This project was looking to get similar results to Schweitzer’s research and to find a simple test method for the initial ...
On The Aquatic Habits Of Sauropods – An Antiquated Theory In Need Of Revival?,
2016
Cedarville University
On The Aquatic Habits Of Sauropods – An Antiquated Theory In Need Of Revival?, Michael D. Sprague
The Research and Scholarship Symposium
When sauropods were first discovered, they were thought to have been restricted to life in the water due to their immense size. This image of sauropods was dismissed in the 1950’s when it was determined that the lungs would have been placed under massive amounts of pressure at these depths, rendering breathing nearly impossible (Kermack, 1951). However, these experiments failed to consider pneumaticity of sauropod vertebrae and were later dismissed. Sauropods possessed pneumatic features in all their presacral vertebrae, originally identified as weight-saving structures. These features kept the strength and integrity of the bone while dramatically reducing its weight ...
Iron Concretions In The Cretaceous Dakota Formation,
2016
University of Nebraska-Lincoln
Iron Concretions In The Cretaceous Dakota Formation, Anthony Kohtz, Richard Kettler, David Loope
UCARE Research Products
The Cretaceous Dakota Formation contains abundant iron oxide concretions. The precursors to the iron concretions are siderite (FeCO3) nodules that formed in a reducing floodplain environment. A variety of concretion morphologies formed when the precursor siderite nodules were dissolved by oxidizing groundwater in a paleoaquifer. Iron-oxidizing bacteria are able to oxidize aqueous Fe(II) to Fe(III) oxy-hydroxide at microaerophilic and neutrophilic conditions. This study investigated these concretions to determine if there was a microbial element in their formation and to characterize the concretion morphologies present in the Dakota. This is important for complete paleoenvironment interpretations and astrobiology pursuits.
Neogene Changes In Caribbean Paleoproductivity And The Diversity And Paleobiogeography Of Deep-Sea Benthic Foraminifera,
2016
Florida International University
Neogene Changes In Caribbean Paleoproductivity And The Diversity And Paleobiogeography Of Deep-Sea Benthic Foraminifera, Crystal Pletka
FIU Electronic Theses and Dissertations
The Neogene history of Caribbean deep-sea benthic foraminifera was investigated by calculating changes in paleoproductivity, diversity and paleobiogeography ~26 to 2 Ma, which includes the progressive closure of the Central American Seaway. Three hypotheses were tested: (1) Paleoproductivity values prior to closure of the Central American Seaway are similar in both the Caribbean and equatorial Pacific and then diverge by the time of early shoaling events; (2) Diversity values of benthic foraminifera prior to the closure of the Central American Seaway were similar in the Caribbean and EEP, and had changed by the time of early shoaling; and (3) during ...
Surface Scan Of The Squamosal Of Cpc 274,
2016
University of Pennsylvania
Surface Scan Of The Squamosal Of Cpc 274, Brandon P. Hedrick
VP3D Scans
CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).
Surface Scan Of The Dentary Of Cpc 274,
2016
University of Pennsylvania
Surface Scan Of The Dentary Of Cpc 274, Brandon P. Hedrick
VP3D Scans
CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).
Surface Scan Of The Parietal Fragment 1 Of Cpc 274,
2016
University of Pennsylvania
Surface Scan Of The Parietal Fragment 1 Of Cpc 274, Brandon P. Hedrick
VP3D Scans
CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).
Surface Scan Of The Parietal Fragment 2 Of Cpc 274,
2016
University of Pennsylvania
Surface Scan Of The Parietal Fragment 2 Of Cpc 274, Brandon P. Hedrick
VP3D Scans
CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).
Surface Scan Of The Premaxilla Of Cpc 274,
2016
University of Pennsylvania
Surface Scan Of The Premaxilla Of Cpc 274, Brandon P. Hedrick
VP3D Scans
CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).
