Palaeomagnetic evidence for non-rotational deformation along the Nea Anchialos Fault System, Central Greece

Abstract

Four sites in 1.4 Ma old basaltic lavas and two sites in upper Pliocene-lower Quaternary sediments, located both in the hanging-wall and in the footwall blocks of the Nea Anchialos Fault System, have been sampled. This fault system is one of the major E-W trending structures affecting the Thessaly region during Quaternary times.It is possibly connected with the North Aegean Trough to the E and displays recent seismic activity (1980, Volos earthquake). Standard techniques have been used for both field sampling and laboratory analyses. The magnetic carriers were characterised by measuring the thermomagnetic curves, the anisotropy of magnetic susceptibility and the isothermal remanent magnetisation of the samples. Almost all the samples exhibit a reverse polarity. The overall mean paleomagnetic direction is defined by D = 174°, I = –54°, confirming the non-rotational deformation pattern of the Nea Anchialos Fault System as independently inferred from structural investigations.