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Palaeomagnetic properties of the Middle-Upper Devonian Volcanics of the Orkney Islands
Earth and Planetary Science Letters, 1972Abstract Thermal demagnetization and ore microscopy combined with the magnetic colloid technique and measurements of the temperature dependence of saturation magnetization have been carried out on the Middle-Upper Devonian Volcanics of the Orkney Islands.
K.M. Storetvedt, N. Petersen
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Misener Sandstone (Middle-Upper Devonian), North-Central Oklahoma
AAPG Bulletin, 1972ABSTRACT The Misener Sandstone of north-central Oklahoma comprises a somewhat discontinuous sandstone-carbonate rock sequence which is commonly less than 20 ft. thick. It covers a large northwest-southeast-trending belt and produces some oil and gas. The Misener is overlain by, and grades upward into, the Woodford Shale and appears to
Thomas W. Amsden, Gilbert Klapper
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About the problem of the Middle-Upper Devonian boundary in the East European Platform
Vestnik of geosciences, 2023A brief overview of the history of the identification of the Frasnian Stage (Upper Devonian) and the determination of its lower boundary in the stratotype region is presented. The characteristics of the Givetian-Frasnian boundary deposits in the East European platform and the stratigraphic significance of the regional event levels are considered ...
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Spores and the middle-upper Devonian boundary
Review of Palaeobotany and Palynology, 1981The stratigraphic levels most favoured for the Middle-Upper Devonian boundary fall approximately within the range of the ammonoid Pharciceras lunulicosta Zone, i.e. from the Middle varcus Subzone to the base of the Lower asymmetricus Zone of the conodont scale.
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Palaeomagnetism of the middle-upper Devonian Esha Ness ignimbrite, W. Shetland
Physics of the Earth and Planetary Interiors, 1985Abstract The ignimbrite division of the Esha Ness volcanics of W. Shetland has been studied palaeomagnetically. The major blocking temperature spectrum ranges between 650 and 680°C, implying that haematite is the principal remanence carrier. The magnetization build-up is simple: a minor low stability magnetization aligned along the direction of the ...
K.M. Storetvedt, T.H. Torsvik
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Middle-Upper Devonian Clastic Wedge of the Arctic Islands
1991Abstract Carbonate deposition dominated the Franklinian miogeocline from Late Cambrian until earliest Middle Devonian. Following a transgression in early Eifelian (within the costatus-costatus conodont Zone), quartzose clastics replaced carbonates as the dominant sediment type and, from that time until Early Carboniferous, clastic ...
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Middle-upper devonian palaeogeography of North Devon and west Somerset, England
Palaeogeography, Palaeoclimatology, Palaeoecology, 1966Abstract Most of the thick, argillaceous and arenaceous deposits of the Ilfracombe Beds and Morte Slates are considered to have accumulated in shallow-water prodelta and delta-platform environments during Givetian and Frasnian times. The thin, predominantly biostromal limestones in the Ilfracombe Beds also seem to have formed in comparatively shallow-
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Ameghiniana, 2010
The surveyed microflora was recovered from six cores from the Tonono x-1 well in northwestern Argentina. Most of the studied interval corresponds to the Tonono Formation, i.e., the upper part to the Jollin Member and the basal part of the interval may be related to the Michicola Formation. The microflora totals 73 species represented by trilete spores (
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The surveyed microflora was recovered from six cores from the Tonono x-1 well in northwestern Argentina. Most of the studied interval corresponds to the Tonono Formation, i.e., the upper part to the Jollin Member and the basal part of the interval may be related to the Michicola Formation. The microflora totals 73 species represented by trilete spores (
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Geological Society of America Bulletin, 1973
The discovery of Rensselandia cloudi Frost and Langenheim in the Samaria Limestone Member at the base of the Hyrum Formation in north-central Utah has revived the question of the age of the member and has led to a detailed study of ranges of the various elements of the fauna in the member.
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The discovery of Rensselandia cloudi Frost and Langenheim in the Samaria Limestone Member at the base of the Hyrum Formation in north-central Utah has revived the question of the age of the member and has led to a detailed study of ranges of the various elements of the fauna in the member.
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Actual problems of the modern palynology. Материалы XV Всероссийской палинологической конференции, посвященной памяти доктора геолого-минералогических наук В.С. Волковой и доктора геолого-минералогических наук М.В. Ошурковой, 2022
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