Skip to main content
U.S. flag

An official website of the United States government

Breaking plates: Creation of the East Anatolian fault, the Anatolian plate, and a tectonic escape system

May 16, 2023

Lateral movement of lithospheric fragments along strike-slip faults in response to collision (escape tectonics) has characterized convergent settings since the onset of plate tectonics and is a mechanism for the formation of new plates. The Anatolian plate was created by the sequential connection of strike-slip faults following ≥10 m.y. of distributed deformation that ultimately localized into plate-bounding faults. Thermochronology data and seismic images of lithosphere structure near the East Anatolian fault zone (EAFZ) provide insights into the development of the new plate and escape system. Low-temperature thermochronology ages of rocks in and near the EAFZ are significantly younger than in other fault zones in the region, e.g., apatite (U-Th)/He: 11–1 Ma versus 27–13 Ma. Young apatite (U-Th)/He ages and thermal history modeling record thermal resetting along the EAFZ over the past ~5 m.y. and are interpreted to indicate thermal activity triggered by strike-slip faulting in the EAFZ as it formed as a through-going, lithosphere-scale structure. The mechanism for EAFZ formation may be discerned from S-wave velocity images from the Continental Dynamics–Central Anatolian Tectonics (CD-CAT) seismic experiment. These images indicate that thin but strong Arabian lithospheric mantle extends ~50–150 km north beneath Anatolian crust and would have been located near the present surficial location of the Bitlis-Zagros suture zone (co-located with the EAFZ in our study area) at ca. 5 Ma. Underthrusting of strong Arabian lithosphere facilitated localization of the EAFZ and thus was a fundamental control on the formation of the Anatolian plate and escape system.

Publication Year 2023
Title Breaking plates: Creation of the East Anatolian fault, the Anatolian plate, and a tectonic escape system
DOI 10.1130/G51211.1
Authors Donna Whitney, Jonathan Delph, Stuart N. Thomson, Susan L. Beck, Gilles Brocard, M. Cosca, Michael H. Darin, Nuretdin Kaymakci, Maud J.M. Meijers, Aral Okay, Bora Rojay, Christian Teyssier, Paul J. Umhoefer
Publication Type Article
Publication Subtype Journal Article
Series Title Geology
Index ID 70260123
Record Source USGS Publications Warehouse
USGS Organization Geology, Geophysics, and Geochemistry Science Center
Was this page helpful?