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Miocene to Pleistocene Calcareous Nannofossil Biostratigraphy from IODP Expedition 334 Hole U1381A and Expedition 352 Hole U1439AUnknown Date (has links)
IODP Expedition 334 drilled west of the Costa Rican coast just offshore of the Osa Peninsula with Hole U1381A being the focus for this study. The preservation of the calcareous
nannofossils at this hole ranges from moderate to good, while the total abundance ranges from very rare to very abundant. The nannofossil assemblages fall into two different zones, NN19 of
the Pleistocene and NN5 of the Miocene. There are about 12 million years missing between these two zones. This hiatus is believed to be the result of erosion based on reworked Pliocene
specimens in Pleistocene samples. A scheme by de Kaenel (1999) was used to further subdivide Zone NN19, and it was determined that Core 6H fell into de Kaenel's datum 18. An article by
Anthonissen and Ogg (2012) was used to define Zone NN5 and to determine the relative age. IODP Expedition 352 drilled west of the Izu-Bonin-Mariana system, just east of the fore-arc of the
subduction zone. Hole U1439A is the focus for this study. The preservation of the nannofossils from Cores 5H to 7H ranges from moderate to good while preservation in Cores 9H to 14X ranges
from moderate to poor. The latter is due to an increase in diagenesis below the lysocline where some nannofossils begin to dissolve or become overgrown. The total abundance for all of
these slides ranges from very rare to very abundant, similar to Expedition 334. These slides fall into seven different zones, CN12a, NN14, CN10b, NN11a, NN7, NN6, NN5, and NN3. Anthonissen
and Ogg (2012) was used to define the majority of these zones while Perch-Nielsen (1989) was used for the remainder. The 12 million year hiatus is not observed at this site; only small
intermittent gaps between zones were noted. / A Thesis submitted to the Department of Earth, Ocean, and Atmospheric Sciences in partial fulfillment of the Master of Science. / Fall Semester 2015. / November 9, 2015. / IODP 334, IODP 352, Miocene, nannofossil, Pleistocene / Includes bibliographical references. / Sherwood W. Wise, Jr., Professor Directing Thesis; William Parker, Committee Member; Leroy Odom, Committee Member.
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Calcareous Nannofossil Biostratigraphy of the Brazos River Area, Falls County, TexasUnknown Date (has links)
The Brazos River area is located at the entrance of the former Western Interior Seaway on the shallow northern Gulf of Mexico shelf. Marine sediments in the region were deposited in
a middle to outer shelf environment. Outcrops on the Brazos River in the Falls County area of Texas record nearly continuous and predominantly siliciclastic sedimentation during the Late
Cretaceous and early Paleogene. The Cretaceous-Paleogene (K-Pg) boundary there, as well as the Upper Cretaceous and Paleogene sediments around it, are clay-rich marls with excellent
preservation. The main goal of this study is to document the well-preserved Upper Cretaceous (Campanian-Maastrichtian) nannofossils with a low resolution look across the K-Pg boundary into
the lowest Paleocene sediments. In this study, seven outcrop sections from the Upper Cretaceous Marlbrook, Neylandville and Corsicana Formations and the lower part of the Danian Kincaid
Formation from the Brazos River area were examined for calcareous nannofossils. The nannofossil assemblages are abundant and diverse in the Campanian and Maastrichtian sections, and
abundant with low diversity in the lower Danian. The samples yielded 6 biozones defined by 7 nannofossil datums. Of these datums, five first occurrences (FO), one last occurrence (LO) and
one first occurrence acme were observed. Based on quantitative analysis 54 genera and 108 species were identified in this study. / A Thesis submitted to the Department of Earth, Ocean and Atmospheric Sciences in partial fulfillment of the Master of Science. / Fall Semester 2015. / November 13, 2015. / Biostratigraphy, Brazos River, Campanian, Maastrichtian, Nannofossils, Texas / Includes bibliographical references. / Sherwood W. Wise, Jr, Professor Directing Thesis; Yang Wang, Committee Member; William C. Parker, Committee Member; John V. Firth, Committee
Member.
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CALCAREOUS NANNOFOSSIL PALEOBIOGEOGRAPHY IN THE CRETACEOUS GREENHORN SEAUnknown Date (has links)
Two distinctive, laterally traceable bentonite beds were used to construct two isochronous time slices through the marine sediments of the Upper Cretaceous Greenhorn Cyclothem of the United States Western Interior Basin. Calcareous nannofossil assemblages from these time slices were examined from more than 40 outcrop localities. Nannofossil presence and assemblage diversity and composition were statistically analyzed to examine the paleooceanographic conditions within the basin. / The lower time-slice (X bentonite) is at the stratigraphic horizon which approximately corresponds to the time at which free communication between the basin and open oceanic systems first occurred. The most striking trend in the nannofossil distribution is delineated by the presence or absence of nannofossils. The presence of common to abundant nannofossils in the center of the basin (i.e., near the hingeline of the basin) and the absence of nannofossils from the eastern and western margins indicate that open oceanic conditions conducive to significant standing crops of calcareous nannoplankton existed only in a narrow, centrally located channel. Conditions at the basis margins were probably unsuitable for large populations due to salinity constraints. Multivariate analyses of this time-slice indicate the presence of two distinct biofacies: a northern biofacies determined by relatively high abundances of Biscutum ellipticum and Zygodiscus sp. 1, and a southern biofacies determined by high abundances of Watznaueria barnesae. / The upper time-slice (HL-3 bentonite) samples the nannofossil distribution at a point at or near the maximum transgression of the Greenhorn Sea. In this time-slice, nannofossils occur beyond the limits of the study area or, in Kansas, beyond the erosional limits of the Cretaceous. Diversities are significantly higher, with the highest values occurring in the northern and southern portions of the study area. Multivariate analyses of this time-slice indicate the presence of three distinct biofacies: a northern biofacies determined by relatively high abundances of Cretarhabdus crenulatus, a southern biofacies determined by high abundances of a diverse assemblages of species including Watznauerla supracretacea and Prediscosphaera columnata, and a western biofacies delineated by high abundances of Biscutum ellipticum. / Source: Dissertation Abstracts International, Volume: 45-09, Section: B, page: 2853. / Thesis (Ph.D.)--The Florida State University, 1984.
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LATE CAMPANIAN AND MAESTRICHTIAN CALCAREOUS NANNOPLANKTON BIOGEOGRAPHY AND HIGH-LATITUDE BIOSTRATIGRAPHYUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 40-09, Section: B, page: 4180. / Thesis (Ph.D.)--The Florida State University, 1979.
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Jurassic nannofossils from PortugalUnknown Date (has links)
Jurassic nannofossil research has progressed to the point where more detailed work is necessary. Existing biostratigraphic problems and initial paleogeographic inquiries cannot be addressed until taxonomic concepts have stabilized and stratigraphic distributions are better understood and correlated to a regional standard. / Most of what is known has come from study of the French and English Jurassic. This is a study of the taxonomy and stratigraphy of Portuguese Jurassic nannofossils. It is the most comprehensive and detailed investigation of its kind on this period to date and is intended to serve as a reference for comparison with other Jurassic localities. Portugal offers an excellent opportunity for such a study because several long, nearly continuous outcrops of Jurassic strata have been described, dated by ammonites and are largely represented by lithologies containing nannofossils. The nine sections studied provide stratigraphic coverage for each interval at two or more localities. Thus, a reproducible nannofossil zonation has been developed for the Portuguese Lower and Middle Jurassic (upper Sinemurian-middle Callovian) and correlated to the ammonite stratigraphy. Upper Jurassic nannofossils were recovered only from the uppermost Oxfordian-lowermost Kimmeridgian. This short interval contains the oldest known representatives of the genera Eiffellithus, Micrantholithus, Microstaurus, and Tubodiscus. Periods of dramatic assemblage turnover in the nannofossils have been identified in the Pliensbachian and Bajocian. / Considerable effort has been made to clarify taxonomic concepts. Synonymies and/or descriptions are accompanied by photomicrographs for all of the taxa recognized in the Portuguese Jurassic. One family, four genera, thirty-six species, one variety, and ten combinations are proposed as new. The following taxa are described: Axopodorhabdus adamanteus, Trapezapheles algarvensis, Pseliosphaera attenuata, Crepidolithus bajocianus, Cretarhabdus cathetus, Calcivascularis cassidyi, Luterilithus clathratus, Polypodorhabdus cordatus, Palaeopontosphaera cymbalum, Crucirhabdus decussatus, Crepidolithus dogger, Similiscutum gradsteinii, Ethmorhabdus grunii, Stephanolithion hexum var. stephanum, Pseliosphaera hillii, Similiscutum ibex, Eiffellithus inornatus, Calyculus katatonus, Incerniculum knuettelii, Vekshinella lumina, Crepidolithus lusitanicus, Stephanolithion mondegoensis, Discorhabdus noeliae, Triscutum patera, Luterilithus pavimentum, Incerniculum pectinatum, Hexapodorhabdus piperatus, Vekshinella rhombocentrum, Discorhabdus sagresensis, Triscutum skaphos, Crepidolithus sulcus, Triscutum sullivanii, Parhabdolithus tentopons, Incerniculum torquatum, Crucirhabdus trunculocavus, Tubodiscus ufo, Zeugrhabdotus vitreus, and Annulithus vulcanus. / Source: Dissertation Abstracts International, Volume: 49-03, Section: B, page: 0678. / Major Professor: Sherwood W. Wise. / Thesis (Ph.D.)--The Florida State University, 1987.
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Taphonomic Characteristics of Fossils on the Burgess-shale-type SpectrumBroce, Jesse S. 15 April 2019 (has links)
No description available.
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Phylogeny and Evolution of Locomotor Modes in Carnivoramorpha (Mammalia)Spaulding, Michelle January 2011 (has links)
Contained in this thesis are seven chapters, five each with a specific scientific focus relating to the study of basal carnivoramorphans or the evolution of locomotion. Presented here is the first detailed description of the only known postcranial skeletal elements of "Miacis" uintensis, found to differ markedly from previously described "miacids" (a paraphyletic assemblage of early fossil Carnivoramorphans), invalidating the notion that all "miacids" were very similar in their postcranial morphology and locomotor styles. The majority of the differences indicate an animal less well adapted to an arboreal lifestyle than has been inferred for other early "miacid" carnivoramorphans. A new genus and species of basal non-Viverravidae Carnivoramorpha, Dawsonicyon isami, is named and described. This new taxon is dentally compared to all known genera of nonviverravid basal carnivoramorphans, as well as with all known species of the problematic genus Miacis. Both "Miacis" uintensis and Dawsonicyon isami are incorporated into a phylogenetic analysis and preliminary functional interpretations of a scansorial locomotor mode are offered for both of these taxa. Following these two descriptive chapters, over 100 postcranial characters are added to the existing data set, which is dominated by cranio-dental characters. The addition of these new characters permits the inclusion of a large number of basal carnivoraforms known solely or predominantly from postcranial characters, that previously would have been `unplaceable' in a phylogenetic analysis. The resultant phylogeny recovers most of the same clades identified in previous studies, but resolves some relationships differently within the basal carnivoraforms. A novel (unnamed) monophyletic subclade of the Carnivoraformes is recovered, supported in part by characters from both the prior and new data sets. The inclusion of a substantial suite of postcranial characters expands the ability to assess the relationships of basal carnivoramorphan taxa, and permits the inclusion of many taxa represented only by incomplete material. Subsequent to the additional of post-cranial characters the matrix is enlarged again, creating the largest anatomical matrix to date for Carnivoramorpha, with 60 extant and fossil taxa and 243 morphological characters. Taxon sampling emphasizes basal carnivoramorphans, and this matrix includes almost every early species for which significant postcranial or non-dental cranial material is known. Resulting trees support the monophly of Carnivoramorpha, Carnivoraformes, and Carnivora as successively diverging clades, as has been found in previous studies, with excellent resolution of interrelationships of taxa within basal Carnivoraformes. Pangolins are found to be the sister clade of Carnivoramorpha to the exclusion of Creodonta. Basal carnivoramorphan taxa previously used to represent a putative basal condition for the group (e.g., species of Vulpavus) are instead found to be highly nested within a monophyletic subclade that is sister-group to most other carnivoramorphans. Nimravidae is strongly supported as a noncrown Carnivora lineage, in contrast to most prior studies. Finally, the evolution of prehensile tails is examined via the identification of phylogenetically independent osteological correlates of prehensility. These features are examined in all living taxa therian known to have independently evolved a prehensile tail, and a close relative that lacks a prehensile capability. This examination reveals that the distal caudal vertebrae are more reliable for the identification of prehensility in a taxon than the more anterior, though there are general trends observed in more proximal caudals. When these indicator features are examined in a complete fossil Cimolestidae from the Green River Formation they allow for the confident identification of prehensility in this specimen. This specimen represents the first known postcranial morphology for the clade Cimolestidae and is the oldest known Eutherian with a prehensile tail.
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Oviraptorosauria: Morphology, Phylogeny, and Endocranial EvolutionBalanoff, Amy January 2011 (has links)
Oviraptorosauria, an extinct lineage of coelurosaurian dinosaurs from the Cretaceous of Asia and North America, includes some of the most morphologically distinctive theropod taxa yet known. Their bizarre appearance and numerous skeletal similarities with extant birds instantly made oviraptorosaurs the subject of considerable interest when first discovered in the early 20th Century by the American Museum of Natural History Central Asiatic Expeditions. Subsequent discoveries have only increased the potential of the group for informing the origin of modern birds and characters that make birds distinctive among living vertebrates, including the origin of flight. The current list of shared similarities between oviraptorosaurs and modern birds includes such striking features as loss of teeth, extreme pneumatization and ornamentation of the skull, an unusual sliding jaw articulation, reduction of the tail vertebrae to form a pygostyle, feathers of modern aspect, and the behavior of brooding eggs in the same stereotypical posture. Despite such an extended period of research and popular interest, some fundamental questions regarding oviraptorosaurs remain. First, what is the phylogenetic position of Oviraptorosauria within Coelurosauria? Recent analyses produce contentious results that disagree on whether oviraptorosaurs represent a clade of bird-like, non-avian coelurosaurs or whether they actually are nested within Avialae. Obviously, these disparate topologies pose disparate models of character evolution. For example, if oviraptorsaurs are avialans they represent the first evolution of flightlessness within that clade. Second, what are the phylogenetic relationships of the taxa comprising Oviraptorosauria? And lastly, what insight would a resolved tree topology provide the study of morphological evolution, both within Oviraptorosauria specifically and more generally within Coelurosauria? I analyzed 384 morphological characters and recovered two most parsimonious trees that resolve both the position of Oviraptorosauria within Coelurosauria as well as the interrelationships of species within Oviraptorosauria. Oviraptorosauria is found to have a sister group relationship with Therizinosauria, and this entire clade is positioned as the sister taxon to the clade formed by (Paraves + Alvarezsauridae). These findings support oviraptorosaurs as non-avian coelurosaurs and thus not avialans. The implication of this topology is that many of the avian-like characteristics expressed in the group are the product of homoplastic evolution between oviraptorids (a more exclusive clade within Oviraptorosauria) and avialans. These phylogenetic hypotheses subsequently are used to elucidate the evolutionary history of endocranial morphology in Oviraptorosauria and more broadly within Coelurosauria near the origin of avian flight. Using the relatively newly employed technology of computed tomography (CT), this study provides descriptive morphology of five coelurosaur endocasts (which approximate the shape of the brain in these taxa that effectively filled the endocranial space) and evaluates shared discreet morphological characters with respect to the aforementioned phylogeny. Diagnostic morphologies are found for Oviraptorosauria and the more exclusive clades, Maniraptora, Paraves, and crown birds. This study also is the first to use CT technology to divide the endocranial casts into six neuroanatomical partitions that correspond closely to the olfactory bulbs, cerebrum, pituitary space, optic lobes, cerebellum, and brain stem. These partitions are then used to evaluate how these different regions of the "brain" are evolving. The division of the endocranial cast into partitions is a novel approach to studying endocranial morphology. Previous analyses have been limited to surveying total endocranial volume and have not been able to distinguish between regions of the brain. Those earlier analyses established that crown birds possess a much larger endocranial space with respect to body size than more distantly related groups and that there is a general transition along the coelurosaur lineage towards an increased endocranial volume. This analysis distinguishes the expansion of the cerebrum as the primary driver of volumetric change within the entire endocranium and identifies three possible expansions of the cerebrum within the maniraptoran lineage. Unique volumetric morphologies are found for both Oviraptorosauria and Paraves. Most interestingly, the volumetric proportions of Archaeopteryx lithographica illustrate that this taxon shares a plesiomorphic morphology with other paravians, suggesting that non-avialan paravians such as Microraptor zhaoianus also possessed what has previously been referred to as a "flight-ready" brain that likely supported some type of volant activity.
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THE PLEISTOCENE CALCAREOUS NANNOPLANKTON OF THE SUBANTARCTIC PACIFIC OCEANUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 31-05, Section: B, page: 2862. / Thesis (Ph.D.)--The Florida State University, 1970.
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Stratigraphy and paleoenvironments of Thetis, Kuper and adjacent Islands, British Columbia /Simmons, Michael Lee. January 1973 (has links)
Thesis (M.S.)--Oregon State University, 1973. / Typescript (photocopy). Some maps folded in pocket. Includes bibliographical references. Also available on the World Wide Web.
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