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Broadband data processing of earthquakes recorded with the seismological network in Denmark and Greenland. P. Voss & T.B. Larsen Geological Survey of Denmark and Greenland - GEUS. ESC 2008, 31st General Assembly. Seismograph network. Denmark. Greenland. ESC 2008, 31st General Assembly.
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Broadband data processing of earthquakes recorded with the seismological network in Denmark and Greenland P. Voss & T.B. Larsen Geological Survey of Denmark and Greenland - GEUS ESC 2008, 31st General Assembly
Seismograph network Denmark Greenland ESC 2008, 31st General Assembly
Core Areas The instruments compose a triangle with sides of approx. 3000km length ESC 2008, 31st General Assembly
Core Events Epicenters JUN 1998 to JUN 2008 ESC 2008, 31st General Assembly
The weekly bulletin: - Single station phase reading. - Phase readings are unassociated. - Location of distant earthquakes: not our problem - Location of local earthquakes: Extra work - Include observations from neighbor networks: Extra work Example of the weekly bulletin ESC 2008, 31st General Assembly
The New Bulletin : - Event based bulletin. - Phase picking and location is preformed in the same working process. - Phase readings are associated with few exceptions. - Location of distant earthquakes: Preformed, but location errors can be very large. - Location of local earthquakes: Done within a few days. - Include observations from other networks: Extra work. Example of the new bulletin ESC 2008, 31st General Assembly
Earthquake Bulletin ESC 2008, 31st General Assembly
Power Spectral Density Probability Density Function Power [10log10(m**2/sec**4/Hz)][db] Ref. : McNamara, D.E., R.I. Boaz, Seismic Noise Analysis System, Power Spectral Density Probability Density Function: Stand-Alone Software Package, USGS Open-File Report, 2005. ESC 2008, 31st General Assembly
Status of the DNK network Improvements : - Defined core areas. - Event based database. - Old analog phase readings have been added to the database. - Macroseismic information is added to the database.Work in progress : - Improve the tools for including information from neighbor networks. - Improve the location and phase association of distant earthquakes. - Upgrade more stations to real time stations. - Registration of known explosions. - PDF quality control Future : - Calibration of the ML magnitude formula. - The generational succession. ESC 2008, 31st General Assembly
Data example – Distant Earthquake M6.6 2008/05/31 04:37 MID-INDIAN RIDGE ESC 2008, 31st General Assembly
Data example – Regional Earthquake ICELAND ESC 2008, 31st General Assembly
Data example – Local Earthquake Baffin Bay ESC 2008, 31st General Assembly
Thank you ESC 2008, 31st General Assembly