Tectonic evolution of Aegean metamorphic core complexes, Andros and Tinos Islands, Greece

dc.contributor.advisorStockli, Daniel F.
dc.contributor.advisorCatlos, Elizabeth J., 1971-
dc.creatorShin, Timothy Andrewen
dc.date.accessioned2014-10-10T15:45:30Zen
dc.date.accessioned2018-01-22T22:26:52Z
dc.date.available2018-01-22T22:26:52Z
dc.date.issued2014-05en
dc.date.submittedMay 2014en
dc.date.updated2014-10-10T15:45:31Zen
dc.descriptiontexten
dc.description.abstractThe Aegean is a classic setting for studying exhumation of high-pressure (HP) metamorphic rocks. Two end-member models are proposed to explain the uplift of these rocks: core-complex style extension along low-angle normal faults and extrusion-wedge uplift. Extrusion-wedge underplating is the mechanism that exhumed HP rocks on Evia whereas Tinos hosts several detachments varying in age from 30-9 Ma. Andros, situated between them, may be the geological manifestation of the interplay of these processes and provides an opportunity to test these models. Detachments on NW Tinos and on Andros and the enigmatic low-angle Makrotantalon Unit contact on Andros were insufficiently dated prior to this study. Geo- and thermochronometrycombined with structural observations from sampling transects in the transport direction from (1) lower plate Cycladic Blueschist Unit on Andros and Tinos, (2) middle plate Makrotantalon Unit on Andros, and (3) hanging wall Upper Unit address these issues. Maximum depositional ages from detrital zircon U-Pb geochronometry and structures reveal Paleocene-Eocene syn-HP metamorphism thrusting resulted in an inversed-age relationship between the Permian Makrotantalon Unit and the underlying Triassic-Eocene Cycladic Blueschist Unit on Andros. The Makrotantalon Unit has an internal inversed stratigraphy whereas the Cycladic Blueschist Unit on Andros and Tinos appear stratigraphically intact. Structures and zircon and apatite (U-Th)/He ages in transects from NW Tinos (~12-8 Ma) and central Andros Cycladic Blueschist Unit (~13-7 Ma) indicate rapid cooling due to exhumation associated with the Livada Detachment. Older cooling ages (~16-10 Ma) and structures in the Makrotantalon Unit indicate later brittle strain localization on the Makrotantalon Thrust contact is accommodated by rheologically weaker serpentinites and calc-schists, resulting in slivering of the footwall under the Livada Detachment on Andros. Estimated mean cooling slip rates of the Livada Detachment on Andros of ~3.8 (+1.2/-1.3) km/Myr and 2.1 (+0.2/-0.2) km/Myr on NW Tinos resulted in minimum vertical exhumations of 15 km and 4 km, respectively. The NCDS here accommodated ~12-25% of 60 km of HP-rock exhumation from ~30-7 Ma. We present a tectonic model to elucidate the evolution of the Makrotantalon Unit and the magnitude, temporal, and spatial variability of exhumation via detachments on these islands.en
dc.description.departmentGeological Sciencesen
dc.format.mimetypeapplication/pdfen
dc.identifier.urihttp://hdl.handle.net/2152/26449en
dc.language.isoenen
dc.subjectNorth Cycladic Detachment Systemen
dc.subjectMakrotantalon Uniten
dc.subject(U-Th)/Heen
dc.subjectZirconen
dc.subjectApatiteen
dc.subjectDetrital U-Pben
dc.subjectBlueschistsen
dc.subjectMetamorphic core complexen
dc.subjectCycladic Blueschist Uniten
dc.subjectAegeanen
dc.subjectGreeceen
dc.subjectPelagonianen
dc.subjectGondwanaen
dc.subjectMetamorphic rocksen
dc.subjectAndros Islanden
dc.subjectTinos Islanden
dc.subjectGreeceen
dc.subjectTectonicen
dc.titleTectonic evolution of Aegean metamorphic core complexes, Andros and Tinos Islands, Greeceen
dc.typeThesisen

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