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Neoichnology and Sedimentology of the Fluvial-Tidal Transition Zone of the Columbia River Delta, northwest U.S.A.Dicks, Robynn M Unknown Date
No description available.
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Dual-Mode Georadar Imaging of Biogenic Structures in Sand-Dominated SubstratesThacker, Hayden Andrew January 2022 (has links)
Recognition of large biogenic sedimentary structures (burrows, nests), their differentiation from physical structures (small storm-surge channels, synsedimentary deformation, buried objects), as well as imaging bioturbation in real time remain key challenges in sedimentology and ichnology. To address these issues, this study focused on laboratory and field ground-penetrating radar (GPR) experiments using both traditional time-lapse mode (TLM) and a time-triggered mode (TTM). In three sets of laboratory experiments, substrate consisted of dry, well-mixed, moderately sorted, medium sand common for upper beach (berm/foredune) and aeolian settings. Targets simulating burrowing organisms were placed on a basal layer (L1) buried by ~20-cm-thick cover horizon (L2), both with near identical mean grain size (1.69 and 1.65 ϕ, respectively). Improvements were made to the experimental design, including an experiment with a saline balloon (vertical pull) and a ground-coupled antenna, at varied moisture levels (0%, 3.7%, and 29.5%). High-frequency (2300 MHz) surveys were captured in TTM while manually extracting the target (variable deformation rate; total time window: 20 seconds). Velocities of simulated deformation calculated from time-triggered radargrams have the potential to be used in the field and laboratory to quantify rates of subsurface bioturbation not available by direct observation. Sediment disruption was quantified using standard ImageJ-aided grayscale analysis to detect truncations (breaks in reflection continuity), with an increase of 10-28% relative to undeformed substrate. Similarly, area-based mean grayscale values increased between 8-16% for damp and saturated TLM surveys, respectively. Complementing the laboratory experiments, this research produced one of the first GPR databases of post-emergence sea turtle nests, ichnologically understudied and relatively complex biogenic structures. A simulated structure (Deauville Beach, DE) and two in situ post-emergence sea turtle nests (Sandbridge Beach, VA) were imaged with an 800 MHz antenna, complemented with sediment texture and magnetic susceptibility analyses. The Delaware experiment provided a reference dataset for a full ethological sequence of nesting and emergence, for comparison with few available studies. At Sandbridge, a clear anomaly was identified at the recent Kemp’s Ridley (Lepidochelys kempii) nesting site, including a V-shaped truncation (width: 0.3-0.5 m; depth: ~0.75-0.9 m). At another location, an older (2020) loggerhead (Caretta caretta) nest was imaged and characterized in a similar aeolian ramp setting, which is characterized by a unique combination of upper berm and aeolian granulometric statistics. Numerous ghost crab burrows, with some imaged during surveys, place sea turtle nests into the Psilonichnus ichnofacies, with overprinting representing a contemporary ichnocoenosis rather than a facies shift. This research has wide-ranging implications for: 1) nest recognition in ancient sequences through identification of diagnostic aeolian ramp packages with diagnostic deformation structures; 2) distinguishing nests from morphologically similar paleo-channels based on overall metrics (tiered components) and fill structure, and 3) conservation of endangered species, with novel applications for nest characterization and potential hatchling emergence monitoring. / Geology
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Neoichnology of Two Scincoid Lizards and Pennsylvanian Paleosols: Improving Interpretations of Continental Tracemakers and Soil EnvironmentsCatena, Angeline M. 20 July 2012 (has links)
No description available.
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The Neoichnology of Two Ambystomatid Salamanders, Pennsylvanian Paleosols, and Their Use in Paleoenvironmental, Paleoecological, and Paleoclimatic InterpretationsDzenowski, Nicole D. 25 July 2012 (has links)
No description available.
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Neoicnologia como ferramenta para interpretação de traços fósseis da Icnofauna de aracnídeos da formação Botucatu (cretáceo inferior, bacia do Paraná)Sampaio, Ravi Martins de Almeida 12 May 2016 (has links)
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Previous issue date: 2016-05-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Ichnofossils are abundant in the sandstones of the Botucatu Formation,
Paraná Basin, of Neocomian age. This formation covers much of the Midwest,
Southeast and South of Brazil, and other countries in South America. Several
sandstone samples containing trace fossils were collected and deposited in the
paleontological collection of the Departmento de Ecologia e Biologia Evolutiva
(DEBE) of the Universidade Federal de São Carlos (UFSCar). In this work,
trace fossils attributed to arachnids, i.e. ichnogenera Paleohelcura Gilmore,
1926 and Octopodichnus Gilmore, 1927, were studied and their presence is
recorded for the first time in Brazil. The aim of this study was to infer how
different environmental conditions such as moisture, texture, substrate
inclination and even behavioral aspects of the organisms can affect the
structure of the traces left by different arthropods. To do this, several
neoichnological experiments were made, with six arachnids (two Tityus
serrulatus, one Lycosa sp., one Loxosceles sp., and two individuals of the
family Gonyleptidae) and five individuals of other invertebrate classes (three
insects, one isopod and one diplopod). The experiments consisted on making
the animals walk on a tray with sand of different grain sizes, different
inclinations and different moisture levels. The results of these experiments,
which showed different trace morphologies, according to each imposed
condition, proved the influence of these conditions on the morphology of the
footprints and on the behavior of the studied animals. In addition, these results
showed how, in some situations, for example, in an uphill movement in a slope
of 30° of inclination, it’s possible that animals with highly different track’s shapes
leave very similar tracks, thus making much more difficult the identification of
the track’s producer animal through the analysis of the ichnofossils. It was also
possible to prove how the moisture level and the substrate inclination are
important for the tracks’ preservation. / Icnofósseis são abundantes nos arenitos da Formação Botucatu, Bacia
do Paraná, de idade Neocomiana. Esta formação abrange grande parte do
Centro-oeste, Sudeste e Sul do Brasil, além de outros países da América do
Sul. Várias amostras de arenito contendo icnofósseis foram coletadas e
depositadas na coleção paleontológica do Departamento de Ecologia e Biologia
Evolutiva (DEBE) da UFSCar. Neste trabalho foram estudados os icnofósseis
atribuídos a aracnídeos, ou seja, os icnogêneros Paleohelcura Gilmore, 1926 e
Octopodichnus Gilmore, 1927, registrados pela primeira vez no Brasil. O
principal objetivo deste estudo foi identificar como diferentes condições do
ambiente, como umidade, textura, inclinação do substrato e até mesmo
aspectos comportamentais podem afetar a estrutura dos rastros deixados por
diferentes artrópodes. Para isso foram realizados diversos experimentos
neoicnológicos com seis aracnídeos (dois Tityus serrulatus, uma Lycosa sp.,
uma Loxosceles sp., e dois indivíduos da família Gonyleptidae) e cinco
indivíduos de outras classes de invertebrados (três insetos, um isópode e um
diplópode). Os experimentos consistiram em fazer os animais caminharem
sobre uma bandeja com diferentes granulometrias de areia em diferentes
inclinações e com diferentes níveis de umidade. Os resultados desses
experimentos, que mostraram diferentes formatos dos rastros de acordo com
cada condição imposta, comprovaram a influência dessas condições na
morfologia das pegadas e no comportamento dos animais estudados. Além
disso, esses resultados mostraram como em algumas situações, por exemplo,
em um movimento de subida em relevos de 30° de inclinação, é possível que
animais com morfologias acentuadamente diferentes deixem rastros muito
semelhantes, o que dificulta a identificação do animal produtor por meio da
análise de icnofósseis. Também foi possível comprovar como a umidade e a
inclinação do substrato são importantes na conservação dos rastros.
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The Neoichnology of Juliform Millipedes and Upper Monongahela to Lower DunkardGroup Paleosols: A Multi-Proxy Approach to Paleolandscape VariabilityBowen, Jared J. January 2013 (has links)
No description available.
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Neoichnology of Tropical and Arid Burrowing Scorpions: Environmental Impacts on Burrow Construction and FormHouser, Skyler K. 05 June 2023 (has links)
No description available.
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Burrowing Techniques, Behaviors, and Trace Morphologies of Extant Larval to Adult BeetlesWislocki, Joseph 03 June 2021 (has links)
No description available.
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Neoichnology of the Burrowing Spiders <i>Gorgyrella inermis</i> (Araneae: Mygalomorphae) and <i>Hogna lenta</i> (Araneae: Araneomorphae)Hils, John M. 24 September 2014 (has links)
No description available.
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Using Ichnology and Sedimentology to Determine Paleoenvironmental and Paleoecological Conditions of a Shallow-Water, Marine Depositional Environment: Case Studies from the Pennsylvanian Ames Limestone and Modern HolothuriansSmilek, Krista R. 21 September 2009 (has links)
No description available.
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