Petrology of the Oman Ophiolite
Published:January 01, 2014
Based on detailed stratigraphy, petrology and geochemistry, the initial arc magmatism of the Oman Ophiolite consisting of tholeiitic lavas followed by boninite flows and tephras is studied in the Wadi Bidi area, northern Oman Mountains. An 1110-m-thick V2 sequence is divided into the lower 970 m (LV2) and upper 140 m (UV2) thick subsequences by a 1.0-m-thick sedimentary layer. Pahoehoe flows dominate in the lower part of the LV2, while the upper part consists mainly of sheet flows with sparse interbedded pelagic sediments and a cylindrical plug. In addition to the presence of a feeder conduit, the flow-dominant lithofacies with a few thin sedimentary interbeds in the LV2 indicates that the study area was the centre of a volcano grown in a short period. The UV2 is composed of boninite sheet flows overlain by a 2.0-m-thick pyroclastic fall deposit. A small amount of boninite lavas at the end of the V2 sequence overlain by thick pelagic sediments suggests that the subduction-related arc volcanism was short lived and terminated long before the ophiolite obduction.
Locations, mode of occurrence, phenocryst assemblages and bulk-rock major and trace element compositions of lavas in the Wadi Bidi area are available at http://www.geolsoc.org.uk/SUP18684.
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Tectonic Evolution of the Oman Mountains
The Oman Mountains contain one of the world's best- exposed and best-understood fold–thrust belts and the largest, best-exposed and most intensively studied ophiolite complex on Earth. This volume presents new international research from authors currently active in the field focusing on the geology of the Oman Mountains, the foreland region, the carbonate platforms of Northern and Central Oman and the underlying basement complex. In addition there is a particular focus on geoconservation in the region. The volume is divided into three main sections that discuss the tectonics of the Arabian plate using insights from geophysics, petrology, structural geology, geochronology and palaeontology; the petrology and geochemistry of the Oman Ophiolite and the sedimentary and hydrocarbon systems of Oman, drawing on the geophysics, structure and sedimentology of these systems. The volume is enhanced by numerous colour images provided courtesy of Petroleum Development Oman.