Evidences of recent fault activity in Lithuania from precise geodetic levelling data

Abstract

Lithuania is considered as tectonically stable region located in the western part of the East European Craton overlain by the Baltic sedimentary basin. Throughout the Phanerozoic the basin was subject to several phases to tectonic activity that led to selective (often utilised Proterozoic structural features) faulting of the Earth’s crust. The most intense faulting took place 425-410 Ma ago. The recurrent measurements of the National Levelling Network provide important information on the recent vertical ground movements. The areas manifesting subsidence and uplift trends at a rate of a few mm/a were defined in Lithuanian territory. A number of sharp gradient zones were traced against the background vertical movements. Analysis of available geological and geophysical data indicates that those zones are in many cases related to faults and fault zones. The rate of vertical movements attain 0.5-1 mm/a. Those data are important for evaluation of the seismic hazard, territorial planning.