Geologically, the mountain range is part of the Tatra-Fatra Belt of core mountains. There are several active faults, which have produced earthquakes. Of them the most notable is the Dobra Voda fault (1906 and 1930 produced 8.5° and 7.5° EMS-98 or equal to formula_1 = 5.7 and 5.0). This particular fault is closely monitored because of its proximity to the NPP Jaslovske Bohunice (approx. 15 km away). The Little Carpathians are seismically one of the most active regions in Slovakia and epicentres of earthquakes with approximate magnitude of 2.5 on Richter magnitude scale are located here.