Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.583721
Title: Geochemical mapping of the extrusive sequence of the Troodos Ophiolite, Cyprus : an investigation into the relationship between lava compositions and proximity to a paleo-subduction zone and a paleo-transform fault
Author: Wake, Charles Alexander
Awarding Body: Cardiff University
Current Institution: Cardiff University
Date of Award: 2005
Availability of Full Text:
Access through EThOS:
Access through Institution:
Abstract:
Analysis of 240 samples for a wide suite of major and trace elements enable geochemical maps of the extrusive series of the Troodos Massif using ArcView 3.2 (a Geographic Information Systems application). Proxies for mantle source depletion, degree of partial melting, lithospheric component, subduction-derived input and fractional crystallisation form the basis of the maps. No substantial difference in mantle source depletion or subduction-derived component was detected between the three stratigraphically-defined lava units (Basal Group, Lower Pillow Lavas and Upper Pillow Lavas). Variation between the lava units is a function of the degree of partial melting of the mantle source and the degree of fractional crystallisation of the resulting magma, both of which are generally highest in the Basal Group and lowest in the Upper Pillow Lavas. Proximity to the paleo-transform fault has three effects on lava composition prior to component addition. Lavas within 10 km of the fault become increasingly primitive. The mantle source becomes strongly depleted on approximately the same scale. The lithospheric (OIB-like) component is also greatest close to the fault. The subduction-derived component is greatest in the north west of the Troodos Massif, in crust generated at the Solea Graben, the oldest of the grabens within the Troodos Massif. The younger Mitsero and Larnaca Grabens have progressively lower subduction-derived components. Taking into account rotation of the Troodos Massif since its formation, the areas of strongest subduction enrichment originally lay to the north. Therefore, the paleo-subduction zone where the Paleotethys ocean floor was being subducted beneath the Troodos supra-subduction spreading centre probably lay to the north of Cyprus, with a southerly dip.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.583721  DOI: Not available
Share: