EPOS-N - European Plate Observing System
Seismometers / vault construction
Stations: Upgrade/install notes
Ideas for improvements
Installation / Inventory
TABLE OF CONTENTS
Location of four seismic stations on Jan Mayen.
There are four seismic stations on the Jan Mayen island. Three are part of the Norwegian National Seismic Network (NNSN) and one is operated by Norsar as part of the monitoring regime in the Comprehensive Test Ban Treaty (preparatory commission).
The first seismometer was installed around 1961 near Olonkin City. The two remote sites ULLA (designated "JNE") and LIBERG ("JNW") were added in 1972, and the CTBT station ("JMIC") came in 2002.
The three first seismometers were installed to monitor seismic activity related to the Beerenberg volcano. To provide accurate location of epicenters a certain number of sensors are needed; they must also be sensitive enough to pick up any increase in the occurrence of low-magnitude earthquakes that are likely to precede an eruption. The seismometers will also aid in evaluation of the situation during and after an eruption.
Periodic maintenance is performed by the staff on the Jan Mayen combined Loran-C / meteorological station; personnel from Department of Earth Science, University of Bergen, will normally visit the stations once every year for other types of maintenance (i.e. component or software upgrades). Power to ULLA and LIBERG stations is provided by a combined wind turbine and solar panel system. We consider replacing existing wind turbines - which requires extensive maintenance due to the harsh climate with severe storms and high salinity - with modern vertical turbines which are more robust (see below).
The main purpose of this web page is to document modifications that are made during 2012-13 upgarde. It also outlines possible future design changes, but as no formal decisions have been made in this regard - it must not be viewed as a policy document stating NNSN commitments.
System diagram University of Bergen seismology network Jan Mayen - before 2012 modifications. (Drawing: O.M., Excel file)
26 Aug 2012: New GPS coordinates: 70.926825N, 8.726678W
Click to see JMI/Trolldalen "As Built" documentation
Block diagram JNE Ulla.
Block diagram JNW Liberg.
Four programs are used for collecting, processing and forwarding data.
Seislog collects data from the Güralp DM24 digitizer that is located in Seismo room at base. It handles:
The Güralp SCREAM! software receives serial data from the remote digitizer, via telemetry line.
The Earthworm software receives data streams from Ulla (JNE), Liberg (JNW) and Trolldalen (JMI) Trolldalen data comprises three components from Trillium broadband seismometer, and vertical Z-channel from old S-13 model seismometer (used as backup).