Records of Ground Deformation in Northern Kefalonia by Cosmogenic 36Cl Geochronology

The cosmogenic 36Cl exposure ages in this study provide the first direct chronology of landscape evolution and ground deformation in the Ionian Islands, with a focus on the Thinia Valley and the anticline near Zola in northern Kefalonia, western Greece. At the primary Zola site, cosmogenic 36Cl exposure ages indicate persistent deformation on the eastern limb of the anticline from the Middle Quaternary to historical times. This broad range, spanning both ancient and recent ages, suggests that the anticline has experienced multiple deformation events rather than a single episode. Older ages correspond to a Middle Pleistocene phase of exhumation, while younger ages suggest additional mass-wasting events influenced by climatic and tectonic factors. At the secondary site, southeast of the previous site, ages indicate a steady-state surface where erosion and decay balance cosmogenic 36Cl production, implying a true age beyond the dating range and leaving the slope’s origin indeterminate. Nonetheless, recent tectonic activity on a fault cutting through this surface suggests an actively evolving tectonic landscape continuing into the Holocene.