In May and June, intensive field research is being carried out in the vicinity of Štanjel, where the team is studying one of the most important active geological structures in Slovenia - the Raša Fault. This fault extends from Goriška Brda across the Vipava Valley, Branik, Štanjel, along the Raše Valley, through Senožeče, Vremščice and down to Ilirska Bistrica. The Raša fault is capable of triggering stronger earthquakes, and we would like to know how often such earthquakes occurred in the past. To do this, we are looking for earthquake-induced deformations in young sediments deposited above the fault and analysing them in detail.

Paleoseismological excavation into the sediments above an active fault is used to study the records of past earthquake and to estimate their magnitude (based on the size of the deformation) and age, leading to an understanding of the fault's seismic history, which is key to understanding its future seismic potential. At the current excavation site, we are investigating the contact between fluvial sediments from the Raša stream and alluvial fan deposits from a nearby ravine. Within the trench we have found clear evidence of past earthquakes, which we will date through further laboratory analyses.

To find out more about how earthquakes affect the natural environment, see lecture by Dr Petra Jamšek Rupnik (from 28:30 minutes onwards).