Matches in SemOpenAlex for { <https://semopenalex.org/work/W64897635> ?p ?o ?g. }
Showing items 1 to 73 of
73
with 100 items per page.
- W64897635 abstract "The Bay of Islands Complex, situated on the west coast of Newfoundland, forms the upper slice assemblage of a number of allochthonous slices that were emplaced on platformal carbonate rocks of the ancient North American continental margin during the lower Middle Ordovician. The Complex consists of a complete ophiolite sequence disposed in four main massifs and believed to represent obducted portions of oceanic lithosphere. During early stages of displacement from the oceanic environment, a basal dynamothermal aureole was developed and remains part of the Complex. Temperatures of metamorphism in this aureole suggest that the ophiolitic rocks were just formed and still hot when displaced. This, together with other evidence, suggests their production in a marginal basin or in the environs of a ridge, subduction zone, transform triple point. -- Petrological, mineralogical and chemical data show that the Complex may be divided into a lower series of ultramafic tectonites representing mantle material, and a higher series of cumulate and extrusive rocks capped by clastic sediments which may be correlated with oceanic crust. -- Examination of the tectonite series reveals a lower spinel lherzolite member overlain by harzburgites. Both rock types are cut by numerous deformed and undeformed olivine-pyroxene veins. These veins represent early crystallisation products from a picritic tholeiite magma derived at 18 kb and 1100°C by ~ 23% partial melting of a spinel lherzolite to leave a harzburgite residuum. The remainder of the magma crystallised as different cumulate and extrusive rocks under crustal conditions. -- The petrogenetic model derived from the mineralogy and chemistry implies a rising diapiric body beneath an accreting centre and allows for the production of tholeiitic, transitional and mildly alkaline basalts from a similar parent. The nature of the basalt erupted depends upon rate of upwelling and rate of crysallisation within the diapir. Prolonged fractionation at pressures of 8-18 kb may explain the derivation of off ridge-axis alkaline series. Furthermore, the model places limits on the depths of melting within the rising diapir and suggests that crystallisation takes place at depths of less than approximately 60 km. -- Comparison of the Bay of Islands Complex with oceanic lithosphere and other ophiolite suites suggests it is possibly the ideal type example with which to study oceanic crust/mantle relationships." @default.
- W64897635 created "2016-06-24" @default.
- W64897635 creator A5022358206 @default.
- W64897635 date "1976-01-01" @default.
- W64897635 modified "2023-09-23" @default.
- W64897635 title "The petrology and petrogenesis of the Bay of Islands Ophiolite Suite, Western Newfoundland" @default.
- W64897635 hasPublicationYear "1976" @default.
- W64897635 type Work @default.
- W64897635 sameAs 64897635 @default.
- W64897635 citedByCount "0" @default.
- W64897635 crossrefType "dissertation" @default.
- W64897635 hasAuthorship W64897635A5022358206 @default.
- W64897635 hasConcept C120806208 @default.
- W64897635 hasConcept C127313418 @default.
- W64897635 hasConcept C139498673 @default.
- W64897635 hasConcept C151730666 @default.
- W64897635 hasConcept C154200439 @default.
- W64897635 hasConcept C161509811 @default.
- W64897635 hasConcept C17409809 @default.
- W64897635 hasConcept C192241223 @default.
- W64897635 hasConcept C193944797 @default.
- W64897635 hasConcept C195081551 @default.
- W64897635 hasConcept C23295444 @default.
- W64897635 hasConcept C23923706 @default.
- W64897635 hasConcept C2780364934 @default.
- W64897635 hasConcept C58097730 @default.
- W64897635 hasConcept C5900021 @default.
- W64897635 hasConcept C77928131 @default.
- W64897635 hasConcept C79572550 @default.
- W64897635 hasConceptScore W64897635C120806208 @default.
- W64897635 hasConceptScore W64897635C127313418 @default.
- W64897635 hasConceptScore W64897635C139498673 @default.
- W64897635 hasConceptScore W64897635C151730666 @default.
- W64897635 hasConceptScore W64897635C154200439 @default.
- W64897635 hasConceptScore W64897635C161509811 @default.
- W64897635 hasConceptScore W64897635C17409809 @default.
- W64897635 hasConceptScore W64897635C192241223 @default.
- W64897635 hasConceptScore W64897635C193944797 @default.
- W64897635 hasConceptScore W64897635C195081551 @default.
- W64897635 hasConceptScore W64897635C23295444 @default.
- W64897635 hasConceptScore W64897635C23923706 @default.
- W64897635 hasConceptScore W64897635C2780364934 @default.
- W64897635 hasConceptScore W64897635C58097730 @default.
- W64897635 hasConceptScore W64897635C5900021 @default.
- W64897635 hasConceptScore W64897635C77928131 @default.
- W64897635 hasConceptScore W64897635C79572550 @default.
- W64897635 hasLocation W648976351 @default.
- W64897635 hasOpenAccess W64897635 @default.
- W64897635 hasPrimaryLocation W648976351 @default.
- W64897635 hasRelatedWork W1582060364 @default.
- W64897635 hasRelatedWork W1666893103 @default.
- W64897635 hasRelatedWork W1670667636 @default.
- W64897635 hasRelatedWork W1968512915 @default.
- W64897635 hasRelatedWork W1974291346 @default.
- W64897635 hasRelatedWork W1979053860 @default.
- W64897635 hasRelatedWork W2001176100 @default.
- W64897635 hasRelatedWork W2005778537 @default.
- W64897635 hasRelatedWork W2011353554 @default.
- W64897635 hasRelatedWork W2011929349 @default.
- W64897635 hasRelatedWork W2018876871 @default.
- W64897635 hasRelatedWork W2040349066 @default.
- W64897635 hasRelatedWork W2060557773 @default.
- W64897635 hasRelatedWork W2093834564 @default.
- W64897635 hasRelatedWork W2098352994 @default.
- W64897635 hasRelatedWork W2123200821 @default.
- W64897635 hasRelatedWork W2144920258 @default.
- W64897635 hasRelatedWork W2240957063 @default.
- W64897635 hasRelatedWork W2466126886 @default.
- W64897635 hasRelatedWork W2909341040 @default.
- W64897635 isParatext "false" @default.
- W64897635 isRetracted "false" @default.
- W64897635 magId "64897635" @default.
- W64897635 workType "dissertation" @default.