Results 131 to 140 of about 1,138 (186)

Suprasubduction-zone ophiolites: Is there really an ophiolite conundrum?

2008
Suprasubduction-zone ophiolites have been recognized in the geologic record for over thirty years. These ophiolites are essentially intact structurally and stratigraphi- cally, show evidence for synmagmatic extension, and contain lavas with geochemical characteristics of arc-volcanic rocks.
Rodney V. Metcalf, John W. Shervais
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The Ballantrae ophiolite

Geological Magazine, 1973
SummaryThe Ballantrae complex, variously interpreted in the light of plate tectonics, is reappraised on the basis of comparisons with ophiolites of the Newfoundland Appalachians and the southwestern Pacific. All the main components of a typical ophiolite sequence can be recognized although the sequence has been greatly disturbed by post-emplacement ...
W. R. Church, R. A. Gayer
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Ophiolite obduction and the Samail Ophiolite: the behaviour of the underlying margin

Geological Society, London, Special Publications, 2003
Abstract Samail ophiolite emplacement has become a type-example for ophiolite obduction. Despite this, problems and controversy remain with respect to the age of high- P metamorphism, the vergence of structures in deformed rocks beneath the ophiolite, the suprasubduction character of the ophiolite and the
D. R. Gray, R. T. Gregory
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Oman Ophiolite: The Harzburgite Ophiolite Type

1989
Although the first detailed report on the Oman ophiolite is recent (Reinhardt, 1969), it is now one of the best studied complexes and is often considered to be the best example of ophiolites in the world. It is indeed the largest, with a crescent-shaped extension over 500 km in length and 50–100 km in width (fig.3.1 and 3.2).
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Diamonds in Ophiolites

Elements, 2014
Ophiolites are a newly documented host of diamonds on Earth. Abundant diamonds have indeed been separated from peridotites and chromitites of ophiolites in China, Myanmar, and Russia. In addition, diamond grains have recently been discovered in chromite from the Cretaceous Luobusa ophiolite (Tibet) and the early Paleozoic Ray-Iz ophiolite (polar Urals,
J.-S. Yang, P. T. Robinson, Y. Dilek
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Northern Philippine Ophiolites: Modern Analogues to Precambrian Ophiolites?

2004
Publisher Summary The northern Philippines is a possible modern analogue for some Precambrian greenstone belts. The Philippine islands constitute amateur island arc complex comprising mainly of ophiolites, island arc plutons, volcanics and volcaniclastics, and thick sedimentary basins filled with immature sediments.
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Subduction-Zone Ophiolites and Island-Arc Ophiolites

1977
Although it is often said that typical ophiolites show a definite pseudostratigraphic sequence of rocks and occur in ancient subduction zones, most ophiolites showing a typical sequence occur outside subduction zones, and most ophiolites in subduction zones do not show a regular sequence.
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Petrography and Geochemistry of Ophiolites, Ophiolite Clasts and Triassic Volcanics

1985
The previous chapter has documented the fragmentary preservation of the ophiolites: in the ophiolite units, dolerites, basaltic pillow lavas and oceanic sediments occupy most of the surface. Mafic and ultramafic cumulates are of minor areal importance; they consist of more or less serpentinized ultramafics associated with very minor occurrences of ...
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Geochronology of the Ophiolites

1979
It would be useful to define precisely at the outset the term ophiolite, for it has had various meanings over the course of time. Although, used by Brongniart, Fouquet, Michel-Levy and Dana, one should start with the concept introduced by Steinmann in 1927 to cover the association of peridotites, gabbroes, diabases and spillites, the existence of a ...
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What is an Ophiolite?

1977
Utilization of scientific terms in geology has several inherent problems, particularly when contemplating both process and description. Ophiolite has had a particularly notorious history in this respect because it has been used in various ways by numerous authors (Green, 1971). Originally, Brongniart (1827) utilized ophiolite to describe serpentinites.
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