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Marine paleoecology of the Eads Mill Member, Hinton Formation, Upper Mississippian, West Virginia and VirginiaVance, Timothy January 2007 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains x, 80 p. : ill. (some col.), maps (part col.). Includes abstract. Includes bibliographical references (p. 71-75).
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First fossil record of Staphylea L. (Staphyleaceae) from North America, and its biogeographic implicationsHuang, Yong Jiang, Liu, Yu Sheng, Wen, Jun, Quan, Cheng 01 November 2015 (has links)
The occurrences of Staphylea L. (Staphyleaceae) fossils have been abundantly documented from the Cenozoic of Eurasia, but none has been confirmed from North America to date. In this study, we describe Staphylealevisemia sp. nov. on the basis of seed remains from the latest Miocene to earliest Pliocene of northeastern Tennessee, southeastern USA. The seeds are characterized by a smoothly inflated body, a large hilar scar perforated by several vascular traces and bordered by a distinctive lip-like rim, a cuticle coating the seed coat interior, and seed coat section containing weakly developed tiny lumina. According to the paleogeographic distribution of the genus, it is hypothesized that Staphylea originated from western Eurasia no later than the late Oligocene, and arrived in eastern North America no later than the late Neogene, most possibly through the North Atlantic land bridges like many other seed plants.
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Pliocene Wood from the Gray Fossil SiteMadsen, Owen Fredric, Widga, Chris 06 April 2022 (has links)
The Gray Fossil Site in northeastern Tennessee preserves materials from a 5-million-year-old ecosystem, including wood from nearby trees. Trees provide a unique perspective into ecosystems as they are immobile during their lifetime. As such, tree rings convey information about precipitation and temperature for a given location. As southern Appalachia is one of North America’s most biodiverse regions, and modern climates are warming, understanding the warmer past climate of the Gray Fossil Site can help predict the region’s future. This study consists of three parts: conservation of wood remains, identification of taxonomic groups represented by the fossil wood, and the measured organic content of fossil wood from the Gray Fossil Site. When excavated, the wood is saturated due to a modern local high water table. A variety of drying methods from paleontology, archaeology, and dendrology were compared on saturated samples, from string wrapping to refrigeration, alcohol replacement to microwaving. The method least likely to cause warping and cracking is to wrap specimens in cotton string to slow drying. Microscopic examination of the wood reveals tree rings that have identifying features. Utilizing identification keys for tree rings, each specimen with visible rings can be identified. Taxa represented by fossil wood specimens are like those present in pre-modern forests. Finally, loss on ignition tests reveal that the Gray Fossil Site wood lacks extensive permineralization or mineral replacement. As the wood is 80-90% organic, alpha-cellulose can be extracted. The presence of alpha-cellulose, albeit stained with iron oxides, indicates that future stable isotope analyses are possible.
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Genesis of Carbonate Concretions in the Upper Ludlowville, Middle Devonian of Erie County, New YorkJordan, Frank W. 10 1900 (has links)
<p> Concretions in a zone about 4 m. below the Tichenor Limestone formed just below the sediment water interface. Their growth was initiated about an
organic-rich fossil cluster and was probably completed before
they were more than 5 to 8 m below the sediment surface. Chemical
products of organic decay, notably bicarbonate ions and
ammonia, diffused outward, raising the pH and precipitating
calcite from connate waters already nearly saturated with
respect to calcium carbonate.
These conclusions derive from the shape of the concretions,
from their relation to the enclosing shales, and from their
overall structure , particularly the position of pyritic fossil
clusters. The relative volumes of soluble material (calcite)
in the concretions are consistent with relative pore volumes
through the upper 5 m. of recent, fine-grained, clayey sediments.
The postulated genetic sequence agrees with recent work
on carbonate diagenesis. Restriction of the concretions to
discrete layers was most probably due to a widespread comnbination
of high rates of organic productivity, high rates ·of sedimentation, and low rates of water circulation, that
lasted a short period of time and resulted in the rapid
burial.of much undecomposed organic material. </p> / Thesis / Master of Science (MSc)
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Some Ordovician lingulid brachiopods from Ontario and Quebec.Sinclair, G. Winston (George Winston) January 1945 (has links)
No description available.
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The influence of differential production and dissolution on the stable isotope composition of planktonic foraminiferaErez, Jonathan January 1979 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1979. / Microfiche copy available in Archives and Science. / Bibliography: p. 110-119. / by Jonathan Erez. / Ph.D.
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Studies in Mesozoic reptiles : a revision of the GeosauridaePhizackerley, P. H. January 1954 (has links)
No description available.
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Effects of some physical and chemical variants on aspects of morphology and physiology in certain dominant diatoms of the Clyde EstuaryArthur, A. January 1988 (has links)
No description available.
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Morpholgy and relationships of the earliest archosaursGower, David John January 1994 (has links)
No description available.
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The fate of nitrogen-containing biomolecules in modern and ancient integumentsFlannery, Matthew Brett January 2000 (has links)
No description available.
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