Third party funded individual grant
Start date : 01.11.2016
End date : 31.10.2019
Ophiolites are often used to infer the internal structure of the oceanic crust and the processes by which it is formed, but most ophiolites were not formed in typical mid-ocean ridge settings. Instead, they appear to have formed close to former subduction zones, but the exact tectonic setting in which they were formed is debated. If ophiolites represent fore-arc crust formed during subduction initiation events, then they provide insights into the initiation of subduction zones, an outstanding unresolved question in plate tectonics. If ophiolites were formed in back-arc or plate edge settings they may represent useful analogues for the internal structure of oceanic crust. If they were formed at a ridge-trench-trench or ridge-trench-transform triple junction then they could be used to infer mantle wedge structure and processes. These tectonic models predict different geochemical variations in ophiolite lavas with space and time. We will map out the 3D gechemical structure of the Troodos Ophiolite of Cyprus, one of the best preserved an exposed ophiolites. We will use major and trace element microanaysis of fresh volcanic glass in order to avoid the effects of alteration. Detailed high resolution sampling of sections through the Troodos volcanic section on both the northern and southern margins of the ophiolite will be used to determine the chemical evolution of magmatism and test hypotheses for the tectonic origin of this ophiolite.