Estonian National Seismic Network (EESN)

The Geological Survey of Estonia (EGT) maintains the Estonian National Seismic Network (EESN) under the network code EE. EGT is responsible of seismic monitoring of Estonia as a part of the national environmental monitoring program. Routine seismic analysis is performed in integrated co-operation with the Institute of Seismology, University of Helsinki (ISUH), and detected events are published in ISUH bulletins. The network dates back from 1980 and digital data exist from 1996 on. Initially, only one to three stations were operational. From 2015 on, the network has been expanded using temporary stations. By 2025, eight permanent and two temporary EE stations operate in real time. VSU is a joint station with GEOFON, labelled both as a GE and an EE station. Three older Estonian stations are equipped with Streckeisen STS-2 and Güralp CMG-6T seismometers. Newer sites have Nanometrics Trillium Compact sensors. Data acquisition systems are a combination of Earth Data digitizers and PC with Seiscomp software or Nanometrics Centaurs. Data sampling frequencies are 100 Hz or 250 Hz. Waveform data under network code EE are available from the GEOFON data centre and are fully open.