Results 141 to 150 of about 322 (183)
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Geochemistry of Archaean Metavolcanic Rocks from the Kudremukh Area, Karnataka
Journal Geological Society of India, 1981Abstract Major and trace element data for metabasaits and metaperidotites from the littleknown Archaean volcanic-sedimentary belt at Kudremukh are presented. The dominant rocks are low K tholeiites showing evidence of partial melting from a Zr, Y and Nb enriched, P and Ta depleted mantle source, at depths where garnet was stable in ...
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Petrology of Metavolcanic Rocks in the Bishop Corners – Donaldson Area, Grenville Province, Ontario
Canadian Journal of Earth Sciences, 1973A calc-alkalic suite, with an apparent thickness of 7 km, varies from alkali basalt and tholeiite composition in the lowest part exposed, through andesite flows and pyroclastic rocks, to rhyodacite pyroclastics at the top. Sixty-two chemical analyses demonstrate a single volcanic cycle.
K. Sethuraman, John M. Moore Jr.
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Scottish Journal of Geology, 1993
Synopsis A detailed petrological and geochemical study of metavolcanic schists of the Dalradian Argyll Group of the southern Highlands of Scotland reveals the activity of five main centres of volcanicity. Volcanic activity started with the localized eruption of low HFSE tholeiites comprising the Laoigh Metabasites during the deposition of the
S. Goodman, J. A. Winchester
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Synopsis A detailed petrological and geochemical study of metavolcanic schists of the Dalradian Argyll Group of the southern Highlands of Scotland reveals the activity of five main centres of volcanicity. Volcanic activity started with the localized eruption of low HFSE tholeiites comprising the Laoigh Metabasites during the deposition of the
S. Goodman, J. A. Winchester
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Geochemistry and origin of Archean felsic metavolcanic rocks, central Noranda area, Quebec, Canada
Canadian Journal of Earth Sciences, 1987Felsic magma petrogenesis was studied by analyzing 24 stratigraphically controlled Archean andesite-to-rhyolite lava flows of both tholeiitic and calc-alkalic affinity from the upper Noranda Subgroup, Quebec, using instrumental neutron activation and X-ray fluorescence techniques.
Osamu Ujike, A. M. Goodwin
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Economic Geology, 1985
West Shasta district bimodal volcanics (Copley Greenstone and Balaklala Rhyolite) are members of a low K calc-alkaline suite. They have rare earth element distributions characterized by pronounced light rare earth element depletion and unfractionated heavy rare earth elements. The striking similarities of the rare earth element patterns between the two
A. E. Bence, Bruce E. Taylor
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West Shasta district bimodal volcanics (Copley Greenstone and Balaklala Rhyolite) are members of a low K calc-alkaline suite. They have rare earth element distributions characterized by pronounced light rare earth element depletion and unfractionated heavy rare earth elements. The striking similarities of the rare earth element patterns between the two
A. E. Bence, Bruce E. Taylor
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U-Pb and Th-Pb whole-rock isochrons from metavolcanic rocks of the Carolina slate belt
Geological Society of America Bulletin, 1987Felsic volcaniclastic rocks and massive pyrite of a part of the Carolina slate belt in South Carolina referred to as the “Haile-Brewer block” seem to have remained closed systems with respect to U, Th, and Pb since ∼465 Ma. U-Pb and Th-Pb whole-rock isochrons indicate ages of 466 ± 40 (2σ) and 462 + 53 Ma, respectively. The Pb-Pb secondary isochron age
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Geochemistry of the Yandal belt metavolcanic rocks, Eastern Goldfields Province, Western Australia
Australian Journal of Earth Sciences, 2000Archaean felsic metavolcanic rocks occur throughout the Yandal belt in the north of the Eastern Goldfields of Western Australia where they are most abundant in the higher parts of the stratigraphy. With the exception of the Spring Well Sequence at the southern end of the belt, these rocks are typically dacites showing geochemical affinities with ...
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Geological Society of America Bulletin, 1991
Mafic meta-igneous supracrustal rocks in the east-central part of the western Triassic and Paleozoic belt are interlayered with and appear to predominantly overlie fine-grained clastic and cherty metasedimentary strata. This complex constitutes a lithostratigraphic terrane exposed in the vicinity of Sawyers Bar, California.
W. G. ERNST +3 more
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Mafic meta-igneous supracrustal rocks in the east-central part of the western Triassic and Paleozoic belt are interlayered with and appear to predominantly overlie fine-grained clastic and cherty metasedimentary strata. This complex constitutes a lithostratigraphic terrane exposed in the vicinity of Sawyers Bar, California.
W. G. ERNST +3 more
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Petrography and Geochemistry of the North of Ilgin (Konya) Metavolcanic Rocks
In this study, investigated the geology, mineralogy, petrography and geochemistry of metavolcanic rocks in northern Ilgın (Konya). There are two Paleozoic and Mesozoic metamorphic rock groups in the study area. Alluvium and Neogene sediments are unconformably layered over these rocks.Oral Sarıkaya, Şenel Özdamar
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Geological Society, London, Special Publications, 2004
Abstract Permian volcanic rocks from the Gorzów Wielkopolski region (NW Poland), although pervasively altered by low-grade metamorphism, still preserve the geochemical characteristics of continental mafic volcanic rocks formed by partial melting of an enriched mantle source.
Elżbieta Dubińska +4 more
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Abstract Permian volcanic rocks from the Gorzów Wielkopolski region (NW Poland), although pervasively altered by low-grade metamorphism, still preserve the geochemical characteristics of continental mafic volcanic rocks formed by partial melting of an enriched mantle source.
Elżbieta Dubińska +4 more
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