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AIM third annual meeting October 10-13, 2012 Smolenice castle. Progseis, Ltd. Felt earthquake in the Little Carpathians Mts. source zone (March 5th, 2012) and related seismic activity in the area. Miriam Kristeková 1 , Lucia Fojtíková 1 , Andrej Cipciar 1 ,.
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AIMthird annual meeting October 10-13, 2012 Smolenice castle Progseis, Ltd. Felt earthquake in the Little Carpathians Mts. source zone (March 5th, 2012) and related seismic activity in the area MiriamKristeková1, Lucia Fojtíková1, Andrej Cipciar1, Juraj Sekereš2, Dagmar Sekerešová2, Kristián Csicsay1, Erik Bystrický1 1Geophysical Institute SAS, Bratislava, Slovakia2Progseis, Ltd., Trnava, Slovakia
Outline felt earthquake (Ml=3.1)in the Little Carpathians Mts. source zoneon March, 5th 22:56 UTC basic information about this eartquake paradox in response of the public to this EQ instalations of temporary stations related seismic activity in the area results of the first analyses our plans what to do next
SMOL, D = 18 km ZST, D = 40 km Local earthquake, March, 5th 2012: EQ parameters (manual processing):- 22:56:57.1 UTC, 48.55N 17.12E, h =14 km, Ml = 3.1 /Progseis - 22:56:59.4 UTC, 48.55N 17.16E, h = 5 km, Ml = 2.9 /GFÚ SAV
Local earthquake, March, 5th 2012: EQ parameters (manual processing):- 22:56:57.1 UTC, 48.55N 17.12E, h =14 km, Ml = 3.1 /Progseis - 22:56:59.4 UTC, 48.55N 17.16E, h = 5 km, Ml = 2.9 /GFÚ SAV MODS March,5th 2012
Local seismic network ProgseisNational network of seismic stations GFÚ SAVSeismic stations built in cooperation (GFÚ SAV, USHM AV CR, Progseis) Local earthquake, March, 5th 2012: EQ parameters (manual processing):- 22:56:57.1 UTC, 48.55N 17.12E, h =14km, Ml = 3.1 /Progseis - 22:56:59.4 UTC, 48.55N 17.16E, h = 5km, Ml = 2.9 /GFÚ SAV
LAKS PLAV Earthquake epicenter by various agencies (automatic location) (manual location)
Public and media response to the earthquake – the paradox The first 24 hours(March,6th 2012) People in the villages nearby frightened and anxious (according journalists), receiving a lot of attention in the news in TV and in the press Questions whether the felt event was an earthquake or explosion in nearby military area Almost constantly ringing phones from reporters asking for information and interviewsabout the event (Ml=3 only!) Data preliminary processing,reprocessing with new available data, ... Preparations for the field campaign next day
Public and media response to the earthquake – the paradox • The first 24 hours(March,6th 2012) • announcement with the basic earthquake parameters was prepared and issued in the morning published on our web pageand sent to the press agencies and to the well known media (TV, press)containing also the message asking people who felt earthquake to fill in our macroseismic questionnaire • - press conference in the afternoon • unusually weak response of the public to macroseismic survey
Day after - Field measurements 6 persons in the field (incl. 1 student) - meeting at the headquarters of the Military Areaexplanation of the situationneed to obtain permission to enter into this area then- meeting with the major of the nearest village Studienkatogether with head of the Military Area and his team together with them discussion of possible sites for seismic stations(fulfilling our criteria for selection) few sites were preliminary selected
Day after - Field measurements After selection of the first siteour team was splitted into the 2 groups:- the first oneto have a look at the remaining sitesto make final selection - the second one started to install stations at the first site- > at the end of the day:2single stations1 small array(4 stations: 1 3C, 3 vertical)were succesfully installed
LAKS PLAV Day after - Field measurements temporary stations
Day after - Field measurements Suitable tool to identify aftershocks:Software Nanoseismic Suite(prof. Joswig’s team, Stuttgart) 3/04/2012 04:32 UTC
Day after - Field measurements Suitable tool to identify aftershocks:Software Nanoseismic Suite(prof. Joswig’s team, Stuttgart)
Day after - Field measurements Suitable tool to identify aftershocks:Software Nanoseismic Suite(prof. Joswig’s team, Stuttgart)
Related seismic activity in the area Little Carpathians, Mts. – active seismic zone in Slovakiamajor known earthquake : 1906 M = 5.7, I0 = VIII-IX EMS98(Dobra Voda area) subarea of the felt earthquake-> SW from Dobra Voda From historical data:earthquake in 1890, M = 4.51914, M = 5.11964, M = 4.21976, M = 4.7 previous felt earthquakes1991 M = 2.6, M = 2.9
08/2011 03/2012 Related seismic activity in the area Recent seismic activity - development in time(6/2010 – 6/2012, 83 eartquakes)
08/2011 03/2012 Related seismic activity in the area Recent seismic activity - development in time(6/2010 – 6/2012, 83 earthquakes) normalized energy released per month
08/2011 03/2012 Related seismic activity in the area Recent seismic activity - development in time(6/2010 – 6/2012, 83 earthquakes)
08/2011 03/2012 Related seismic activity in the area Recent seismic activity - map view(6/2010 – 6/2012, 83 earthquakes)
Zuzana Jechumtalova (personal comm.): MT STI 21/10/2012 15:58:39.8 , Ml = 2.4 Focal mechanism of the main shock 5/03/2012 22:56:57.1 , Ml = 3.1 FOCMEC we plan to use also another method for the main event and to compute focal mechanisms for more events from this area
Macroseismic survey - results 32 observations Several reports damages Indications that macroseismiceffects could be stronger in direction to the northlocal effect?
Conclusions • We have presented preliminary results onlyand we have a lot to do: • calculate focal mechanisms for more events- relocate related events using relative location techniqueto identify active faults • - investigate possible local effect(noise measurements)-improve our field equipment