Marine magnetotellurics on a continental margin [Elektronische Ressource] : imaging the hydration and dehydration cycle of the Costa Rican subduction zone / vorgelegt von Tamara W. D. Worzewski

Marine Magnetotelluricson a Continental Margin:Imaging the Hydration and DehydrationCycle of the Costa Rican Subduction ZoneDissertationzur Erlangung des Doktorgradesder Mathematisch-Naturwissenschaftlichen Fakultätder Christian-Albrechts-Universität zu Kielvorgelegt vonTamara W. D. WorzewskiKiel, März 2011Referent: Dr. M. Jegen-KulcsarKoreferent: Prof. Dr. H. KoppTag der mündlichen Prüfung: 26.05.2011Zum Druck genehmigt: 26.05.2011Der DekaniiiiiiAbstractAtcontinentalmargins,thewatercontentanditsdistributionplayanimportantrolein the subduction process. Water is released from the subducting slab in a series ofmetamorphicreactionsandmaytriggertheonsetofmelting,causecrustalweakeningand changes in the dynamics and thermal structure of subduction zones. However,the amount of water carried into the subduction zone and its distribution are notwell constrained by existing data. They are subject of vigorous current research inthe special research initiative (SFB 574) at University of Kiel and IFM-GEOMAR“Volatiles and Fluids in Subduction Zones: Climate Feedback and Trigger Mecha-nisms for Natural Disasters”.Electromagnetic methods like magnetotellurics have been widely used to recognizefluid release and melt production through enhanced electrical conductivities. In theframework of SFB 574, an offshore magnetotelluric experiment was performed in2007-2008 along a profile crossing the trench, where the Cocos plate is thrust be-neath the Caribbean plate.