Velocity field and crustal deformation of broader Athens plain (Greece) from a dense geodetic network

Abstract

The broader area of Athens, a region exhibiting relatively low crustal deformation, was stroke in 1999 by a catastrophic earthquake posing serious questions regarding strain accumulation in slow deforming regions located within active geodynamic regimes. In the present study, the establishment of a dense geodetic network, primarily designed to monitor local tectonic movements is reported. A comprehensive GNSS velocity field, over the period 2005–2008, as well as calculated geodetic strain rates is presented. It is shown that a single strain tensor is insufficient to express the heterogeneity of the local geodetic field. Local variability of strain is successfully depicted, indicating the western part of Athens as the area of higher strain accumulation. Maximum dilatation rates occur along a NNE-SSW direction between Parnitha Mt. and Thriasio basin. The observed dilatation can be associated to WNW-ESE trending active fault zones, which appear to abruptly terminate towards East along a major NNE-SSW Miocene tectonic boundary. These findings are consistent to the stress field responsible for the Athens 1999 earthquake, also in agreement with geological and tectonic observations. Finally, the implications of the observed motion field on the understanding of the kinematics and dynamics of the region as well as the role of inherited inactive tectonic structures are discussed.

The use of geochemical ratios in groundwater quality assessment: the case of the Thriassion Plain, Attica, Greece

“…The Palaeozoic basement is represented by a volcanosedimentary complex consisted of (a) clastic materials, shales and sandstones; at the top. The geological structure of the narrow area of Thriassion Plain is very complex, due to different sedimentary environments and facies alternations of torrential, lacustrine and lagoon sediments deposited during Neogene-Quaternary period as well as the effects of tectonic and neotectonic deformation Ganas et al, 2004;Foumelis, 2019). This structure has influenced the geomorphological, hydrological and hydrogeological characteristics of the above-mentioned area.…”