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Showing 1 to 13 of 13 for “"Late Silurian"”.
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Late Silurian and Early Devonian fossil plants of Bathurst Island, arctic Canada
… or rarely pyrite permineralizations in rocks of Late Silurian and Early Devonian age. Specimens of some taxa are numerous and, sometimes, almost complete, allowing analysis of intraspecific variability, developmental patterns and reconstruction of the whole plant. The majority of plant fossils …
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Stratigraphy and conodont paleontology of late Silurian-early Devonian strata of western Virginia
Biostratigraphic study of the Late Silurian-Early Devonian strata of western Virginia reveals the presence of at least three potentially useful multielement conodont apparatuses. Two multielement species of the genus Ozarkodina may prove to be useful in determining the boundary between the Silurian …
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Geo- and biodynamic evolution at the northern margin of Gondwana during Late Silurian to Early Devonian time (Hazro Area, SE Turkey)
… literature survey of 24 worldwide occurring Silurian/Devonian boundary sites and a subsequent organic geochemical evaluation of eight of these locations from Turkey, Morocco, Ukraine, Poland as well as from the stratotype section in the Czech Republic revealed that the organic matter of …
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Orbital-scale fluctuations in continental weathering flux and continental ice-volume during greenhouse and icehouse climate intervals : evidence from oxygen and neodymium isotopes
… during two global greenhouse intervals: the Late Silurian and Late Devonian. The first study (Chapter 1) explores whether glacio-eustasy was the driver for orbital-scale shallowing-upward cycles developed in Late Silurian and early Late Devonian tropical and subtropical greenhouse climates. …
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Architecture of the Silurian sedimentary cover sequence in the Cadia porphyry Au-Cu district, NSW, Australia : implications for post-mineral deformation
… of the Cadia district are associated with Late-Ordovician monzonite intrusions, which were emplaced during the final phase of Macquarie Arc magmatism at the end of the Benambran Orogeny. N-striking faults, including the curviplanar, northerly striking, moderately west-dipping basement …
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Sedimentology, petrology, and structure of the Moffet Creek Formation, Eastern Klamath Mountains, Northern California
The stratigraphy and tectonic significance of the Late Silurian-Early Devonian(?) Moffett Creek Formation are poorly understood because of structural complexity and the dearth of fossils. Elsewhere, the Moffett Creek Formation has been interpreted as melange, because abundant sandstone phacoids are …
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Fluid inclusions: evidence for a counterclockwise P-T trajectory in the Central Maine terrane of South-Central Massachusetts
Acadian (Late Silurian-Early Devonian) metamorphism in the Central Maine Terrane (CMT) in central Massachusetts is characterized by an early low-P, high-T (Buchan-type) metamorphism followed by compression and nearly isobaric cooling to 100-200°C below peak recorded temperatures before eventual …
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Bedrock geology of the seacoast region of New Hampshire, United States
… suggest that deformation of the crystals is related to folding that affected the host rock and not to the emplacement of a nearby Mesozoic dike.</p><p>Fieldwork, microstructural analysis, and digital elevation models, provide refinement of the traces of the Calef, Nannie Island, Portsmouth, and …
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Aspects of Deformation and Strain in the Appalachian Fold -Thrust Belt (New York) and the Shear Zones of the Sveconorwegian Orogen (Norway)
… the structural architecture of the Alleghanian (Late Paleozoic) northern Appalachian foreland fold-thrust belt, near the town of Rosendale in southeastern New York State. Results suggest that along-strike thinning (from south to north) of rigid units within the Silurian-Devonian stratigraphic …
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Stratigraphy, sedimentology, and diagenetic history of the Siluro- Devonian Helderberg Group, central Appalachians
The Late Silurian-Early Devonian Helderberg Group, Central Appalachians, is a sequence of mixed siliciclastic-carbonate sediments that was deposited during relative tectonic quiescence on a ramp that built out from low-relief tectonic highlands bordering the eastern side of the Appalachian Basin. …
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Structural and Petrologic Evolution of Acadian Dome Structures in Southern Vermont
… of several different models for Acadian (Late Silurian to Middle Devonian) dome evolution in southern Vermont. Previous models considered diapiric uprise and composite nappe-stage crustal thickening and subsequent diapirism as likely causes of dome formation. Both of these previous models …
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Geology of the Big Walker Mountain-Crockett Cove Area, Bland, Pulaski, and Wythe counties, Virginia
… of the sea floor during Middle Ordovician-Late Silurian time. The synclinal trough was the site of maximum subsidence and the anticlinal axis was the site of minimum subsidence. The date of inception of these two folds must correspond to the beginning of pronounced vertical movement of the …
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Causes and Mechanisms of Remagnetisation in Palaeozoic Sedimentary Rocks - a Multidisciplinary Approach
… and Holy Cross Mountains), where the causes of Late Palaeozoic remagnetisations are yet unclear. The results yield important implications for the processes and mechanisms responsible for the remagnetisations in the areas studied. NE Rhenish Massif: A Late Carboniferous remagnetisation (component …