Results 131 to 140 of about 3,037 (183)
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1994
Abstract The Early-Middle Llandoverian was similar to the end of the Late Ordovician in the general features of palaeogeography and biotas. In the southern hemisphere, Gondwana was still integral, except for a number of small separate plates along its margins, and it was situated mostly in the middle and high latitudes south to 30°S ...
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Abstract The Early-Middle Llandoverian was similar to the end of the Late Ordovician in the general features of palaeogeography and biotas. In the southern hemisphere, Gondwana was still integral, except for a number of small separate plates along its margins, and it was situated mostly in the middle and high latitudes south to 30°S ...
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Quarterly Journal of the Geological Society of London, 1876
I n a paper read last session before the Society, I pointed out some of the most important features of the Hæmatite deposits that occur in the Carboniferous Limestone of Cumberland and Lancashire. Amongst other things I showed that the direction of the deposits was invariably parallel to that of the meridional ...
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I n a paper read last session before the Society, I pointed out some of the most important features of the Hæmatite deposits that occur in the Carboniferous Limestone of Cumberland and Lancashire. Amongst other things I showed that the direction of the deposits was invariably parallel to that of the meridional ...
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Geological Society, London, Special Publications, 1964
Summary Radiometric dates for the Silurian at present depend upon determinations on sediments. Available data suggest a time-span of up to about 50 m.y. for the Silurian period, with upper and lower limits of bout 390 m.y. and 440 m.y. Relations between graptolite zones and the time-scale imply a stratigraphical precision of about 1 m.y ...
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Summary Radiometric dates for the Silurian at present depend upon determinations on sediments. Available data suggest a time-span of up to about 50 m.y. for the Silurian period, with upper and lower limits of bout 390 m.y. and 440 m.y. Relations between graptolite zones and the time-scale imply a stratigraphical precision of about 1 m.y ...
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Journal of the Geological Society, 1990
A detailed stratigraphical study of the Silurian rocks of the Pyrenees and analysis of their graptolite and conodont faunas has allowed the construction of composite lithostratigraphical successions and accurate correlations between them. The lithostratigraphy reflects generally continuous deposition of pelitic and shale sediments across the whole of ...
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A detailed stratigraphical study of the Silurian rocks of the Pyrenees and analysis of their graptolite and conodont faunas has allowed the construction of composite lithostratigraphical successions and accurate correlations between them. The lithostratigraphy reflects generally continuous deposition of pelitic and shale sediments across the whole of ...
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1978
Abstract The newly agreed-upon Silurian-Devonian boundary is an excellent example of a modern high precision definition of a stratotype boundary, based on biostratigraphic evidence. The Ordo- vician-Silurian boundary is being studied by a working group under two subcommittees (Ordovician and Silurian).
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Abstract The newly agreed-upon Silurian-Devonian boundary is an excellent example of a modern high precision definition of a stratotype boundary, based on biostratigraphic evidence. The Ordo- vician-Silurian boundary is being studied by a working group under two subcommittees (Ordovician and Silurian).
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1993
Abstract Most Ordovician and Silurian rocks in western and northwestern Canada were deposited on the North American craton and its western continental margin. Strata of these ages have also been recognized in three allochthonous terranes in the Cordillera, described in the companion volume on the Cordilleran Orogen (Gabrielse and Yorath,
M.P. Cecile, B.S. Norford
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Abstract Most Ordovician and Silurian rocks in western and northwestern Canada were deposited on the North American craton and its western continental margin. Strata of these ages have also been recognized in three allochthonous terranes in the Cordillera, described in the companion volume on the Cordilleran Orogen (Gabrielse and Yorath,
M.P. Cecile, B.S. Norford
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