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A tetrapod fauna from within the Devonian Antarctic Circle
Science, 2018Out of Antarctica When we think of Devonian tetrapods, the ancestors of all modern vertebrates, we tend to picture amphibian-like creatures emerging from the water into a wet tropical forest or swamp.
R. Gess, P. Ahlberg
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Devonian magmatism in the accretionary complex of southern Chile
Journal of the Geological Society, 2016Supposed or potential Devonian igneous rocks in the accretionary complex of southern Chile were investigated using sensitive high-resolution ion microprobe U–Pb dating of zircon, with Hf- and O-isotope analyses of selected grains. Ages of 384 ± 3 and 382
F. Hervé +8 more
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Mudrocks of the Devonian [PDF]
Quarterly Journal of Engineering Geology, 1981 Introduction Around the close of the Silurian, but with associated igneous and volcanic events lasting well into the Devonian, occurred the major phase of the Caledonian Orogeny. The main mountain belt resulting from this, stretched from the joined area of Spitsbergen, E Greenland and Norway SE for some 4000 km, the belt being up to 600 km in
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Geological Society, London, Special Publications, 1964
Summary A review of the radiometric evidence suggests that the top of the Devonian should be dated at about 345 m.y. and the base of the system at about 395 m.y. Using cumulative thickness methods the age of the base of the Upper Devonian is estimated at 358 m.y. and that of the base of the Middle Devonian at 370 m.y.
Peter Furneaux Friend, Michael R. House
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Summary A review of the radiometric evidence suggests that the top of the Devonian should be dated at about 345 m.y. and the base of the system at about 395 m.y. Using cumulative thickness methods the age of the base of the Upper Devonian is estimated at 358 m.y. and that of the base of the Middle Devonian at 370 m.y.
Peter Furneaux Friend, Michael R. House
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Geological Magazine, 1924
My attention has recently been called to some very interesting comments on the problem of the delimitation of the Silurian and Devonian systems, which were made by Dr. Elles in her Presidential address to Section C of the British Association at Liverpool.
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My attention has recently been called to some very interesting comments on the problem of the delimitation of the Silurian and Devonian systems, which were made by Dr. Elles in her Presidential address to Section C of the British Association at Liverpool.
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Nature, 2003
Perhaps the most enduring of puzzles in palaeontology has been the identity of Palaeospondylus gunni Traquair, a tiny (5-60-mm) vertebrate fossil from the Middle Devonian period (approximately 385 Myr ago) of Scotland, first discovered in 1890 (refs 1-3). It is known principally from a single site (Achanarras Quarry, Caithness) where, paradoxically, it
Mark D. Sutton +2 more
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Perhaps the most enduring of puzzles in palaeontology has been the identity of Palaeospondylus gunni Traquair, a tiny (5-60-mm) vertebrate fossil from the Middle Devonian period (approximately 385 Myr ago) of Scotland, first discovered in 1890 (refs 1-3). It is known principally from a single site (Achanarras Quarry, Caithness) where, paradoxically, it
Mark D. Sutton +2 more
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Environmental Science and Technology, 2013
The exponential increase in fossil energy production from Devonian-age shale in the Northeastern United States has highlighted the management challenges for produced waters from hydraulically fractured wells.
E. Barbot +3 more
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The exponential increase in fossil energy production from Devonian-age shale in the Northeastern United States has highlighted the management challenges for produced waters from hydraulically fractured wells.
E. Barbot +3 more
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A Devonian Trilobite with an Eyeshade
Science, 2003Trilobites include the oldest species with preserved eyes for which detailed optical mechanisms have been suggested. They appear in the Cambrian, and in comparison to other species present then, trilobites already had unusually sophisticated eyes with lenses made out of the mineral calcite ( [1 ...
Brian Chatterton, Richard A. Fortey
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Middle Devonian liverwort herbivory and antiherbivore defence.
New Phytologist, 2014To test the extent of herbivory in early terrestrial ecosystems, we examined compression-impression specimens of the late Middle Devonian liverwort Metzgeriothallus sharonae, from the Catskill Delta deposit of eastern New York state.
C. Labandeira +3 more
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A Late Devonian Reef Tract on Northeastern Banks Island, N.W.T.
, 1971The Upper Devonian Weatherall Formation, outcropping on northeastern Banks Island, N.W.T., contains a 200-ft-thick limestone unit here termed the Mercy Bay Member. The member is Middle to Late Frasnian in age.
A. Embry, J. E. Klovan
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