ZAGREB, Dec 31 (Hina) – The European Mediterranean Seismological Centre near Paris never received more reports from people about an earthquake than on Tuesday regarding a 4.15 p.m. tremor with the epicentre near Petrinja, Vecernji List daily said on Thursday.
In a few minutes 22,000 people notified the EMSC, although the tremor was a weaker aftershock following the main magnitude 6.2 earthquake which struck shortly after noon.
The number of reports of the main earthquake certainly would have been higher, but the lines could not withstand so much traffic, said Remy Bossu, seismologist and leader of a nine-member team whose services have been used by many Croats since the March earthquake in Zagreb.
Many will open the EMSC’s Last Quake app as soon as they feel the ground shaking, and in less than 15 seconds they will find out if their senses have deceived them or if it was indeed an earthquake, before seismological institutes even read, let alone publish the location and the magnitude.
The EMSC also detects witness reactions on the Internet before seismologists provide traditional data. To prevent panic-mongers from abusing its information, the EMSC communicates with clients and Croats accept its explanations more and more, the newspaper said.
Croatia was hit by two major earthquakes this year, what did they learn from them? Both, Bossu says, were very specific.
“In March in Zagreb, for the first time we had an earthquake with a magnitude greater than 5.0 in the capital. If the epicenter was 25 kilometers away from Zagreb, it would be a different story. For the first time, we also recorded earthquakes of once very small magnitude, less than 1.0, that people felt. Some even doubted it, but seismic data later confirmed it. The anxiety of the people certainly played a big role in that. The earthquake near Petrinja is also unique. When I was asked after Monday’s earthquake if a major earthquake would follow now or would it calm down, I said the high probability, but not the certainty, was the latter. Namely, in only five percent of cases, the main, strongest earthquake is preceded by a weaker one. It was like that in Petrinja – after the 5.2 magnitude on Monday, the city had a 6.4 magnitude a day later,” Bossu said.