Hostname: page-component-8448b6f56d-c47g7 Total loading time: 0 Render date: 2024-04-24T14:05:41.565Z Has data issue: false hasContentIssue false

Precise U–Pb ages of syn-extensional Miocene intrusions in the central Menderes Massif, western Turkey

Published online by Cambridge University Press:  20 December 2006

JOHANNES GLODNY
Affiliation:
GeoForschungsZentrum Potsdam, Telegrafenberg C2, 14473 Potsdam, Germany
RALF HETZEL
Affiliation:
Geologisch-Paläontologisches Institut, Universität Münster, Corrensstr. 24, 48149 Münster, Germany

Abstract

Western Turkey is an area which has experienced large-scale extension of continental crust. Here we report precise crystallization ages of two intrusions in the central Menderes Massif, the Turgutlu and Salihli granodiorites, using U–Pb dating. Both intrusions occur in the southern footwall of the seismically active Alaşehir graben and were emplaced syntectonically in an extensional top-to-the-NNE shear zone which was active at retrograde greenschist-facies conditions. The U–Pb ages of 16.1 ± 0.2 Ma (monazite, Turgutlu granodiorite) and 15.0 ± 0.3 Ma (allanite, Salihli granodiorite) document that tectonic exhumation of middle-crustal rocks in the central Menderes Massif was already underway at the Early to Middle Miocene transition. Combined with published geochronological, structural and sedimentological data, the new U–Pb ages point to a continued extension since at least 16 Ma. There is no convincing evidence for a late Miocene/Pliocene phase of tectonic shortening.

Type
Original Article
Copyright
© 2007 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)