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Explore the data and events recorded by the Norwegian National Seismic Network in Baltic countries and adjacent territories. Learn about significant earthquakes, aftershocks, and the need for more seismic stations. Access NNSN data online for comprehensive seismic information. Stay informed about seismic activity in the region.
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Norwegian National Seismic Network recording events from the Baltic countries Jens Havskov Presented at International workshop SEISMICITY AND SEISMOLOGICAL OBSERVATIONS OF BALTIC SEA REGION AND ADJACENT TERRITORIES 10–12 September, 2007 VILNIUS, Lithuania,
Stations in NNSN Norwegian National Seismic Network and other seismic stations in Norway. Blue symbols are NNSN stations and red are NORSAR arrays. The station JMIC is operated by NORSAR.
Earthquakes 1990-2004 Four earthquakes are located per day. Known and presumed explosion are not included.
1988 The earthquake of 8-8-1988 Magnitude 5.3
2004, April 16, Mw = 6 earthquake The blue dots are aftershocks occurring within 12 hours after the main shock; the red dots are later aftershocks occurring within 2 months after the main shock. The box outlines the extent of the ruptured fault plane from the aftershock distribution. A and B mark the two clusters of events within the Jan Mayen Platform, which are expected to occur on normal faults.
Hopen Location of the July 4th 2003 Svalbard event. 1 - BER location, 2 - NAO location, 3 - PDE location, 4 - Location of mb=5.5 event on January 18th 1976.
Typical NNSN recording system using SEISLOG The signal is sent to the anlog to digital converter which converts the signal to a digital signal. It is then transferred to a computer, where it is recorded and stored. Via internet, the signal are sent from there to Bergen. The SEISLOG system runs in QNX, Windows and Linux
Data flow in NNSN NNSN station Bergen data International center data center NNSN station NNSN NORSAR
NNSN and the public NNSN is continuously updating information about seismic events . The map shows the events for the last 10 days..
The data consist of: • - Original and data from felt • earthquakes for the last 1000 years • Locations and observations from • NNSN since 1905 • -Waveform data since 1981 NNSN data Most data are available via the WEB
Felt events In case of felt events,, NNSN is collecting information from the public, manually and using the WEB. NNSN has a 24 h telephone service, where the public can get information about current events.
Norwegian National Seismic Network database, 1980-2006 40 000 seismic events located with NNSN and other stations
What we need More seismic stations in Baltic area Better information about mining activity