Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 10 of 10 for “"Fossil preservation"”.
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Contributions to Exceptional Fossil Preservation
Exceptionally preserved fossils—or fossils preserved with remains of originally non-biomineralized (i.e. soft) tissues—constitute a key resource for investigating the history of the biosphere. In comparison to fossils of biomineralized skeletal elements, which represent the majority of the fossil …
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Taphonomic studies of fossil preservation in coarse-grained siliciclastic environments
… and silty sediments commonly preserve microbial fossils and textures as well as the fossils of soft-bodied organisms. The rarity of similar fossils and textures in coarse-grained siliciclastic strata of the later Phanerozoic suggests that a taphonomic window facilitated this mode of fossil …
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Fossil preservation and the effects of groundwater leaching on fossils in the Yorktown Formation (Upper Pliocene), Virginia
Patterns of fossil diagenesis caused by groundwater leaching provide insight into how shells are altered. This study analyzes fossils in unconsolidated terrigenous sediments from the Virginia Coastal Plain, unlike previous studies conducted mostly in carbonate terranes. The vertical and lateral …
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Functional Information in Individual Anterior Tarsal Bones of Anthropoids
… cuneiforms--are promising candidates for good fossil preservation because of their compact shape and density, but are frequently unassociated with the more commonly preserved teeth and mandibular fragments. To be of use in interpreting the evolutionary history of locomotor modes, an anterior …
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Experiments on biomarker preservation
Determining how fossils form, and the nature of organic matter that becomes fossilized and which persists through geologic time, are continuing challenges. This is because decay begins immediately after senescence and diagenetic transformations typically continue progressively over millions of …
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Quantitative approaches and applications to the sequence stratigraphy and biodiversity of Pleistocene – Holocene mollusk communities from the Po plain, Italy and San Salvador Island, the Bahamas
… past marine depositional settings and the preservation potential of various environments in the geological record. While the chapters in this dissertation vary in terms of study area, sedimentary systems (carbonate vs. siliciclastic), depositional environment, and organisms, all projects …
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Paleobiology, Biostratigraphy, and Taphonomy of Neoproterozoic Eukaryotes and Cambrian Animals with Carbonaceous Preservation
Carbonaceous fossil preservation is an important taphonomic window that provides critical perspectives on the evolutionary history of life. However, phylogenetic interpretation of carbonaceous fossils is not straightforward. This is largely because critical biological information is usually lost …
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Climate, Ecology, and Human Evolution during the Plio-Pleistocene
… correlates of isotopic variation in the fossil record, and living primates provide a useful model for understanding the ecological significance of isotopic variation in fossil hominin tissues. Isotope data from modern primate excreta and plants shows that isotopic variation primarily …
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The impact of global environmental changes on exceptional preservation, extinction, and recovery in the early Jurassic (late Pliensbachian-Toarcian)
… carbon dioxide and climate change, and the fossil record can provide critical information about how organisms withstood similar climate crises in the past. During the Early Jurassic there were significant perturbations in environmental conditions around the globe, such as thermal stress, low …
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Taphonomy of pigmentary colours in fossil insects
… displayed in their cuticles. Although fossil insects are abundant and the patternings in their cuticles highly resemble those found in extant insects, these are commonly monotonal, especially in those insects preserved across deep geological time. Colouration mechanisms in extant …