| | On December 29th, 2020, the wider area of Banija was hit by a strong
earthquake with a strength of 6.2 on the Richter scale with an epicenter near town of
Petrinja. The quake, which was also felt outside Croatia's borders, caused the deaths of
seven people and major devastation. Thousands of buildings were destroyed and become
unusable, as well as significant parts of the utility infrastructure. Also, visible traces of
soil movement were observed. Before and after the main quake, the epicentral area was
hit by many aftershocks, several of them with magnitude higher than 4.5 on the Richter
scale.
Before that, on March 22nd, 2020, town of Zagreb was also hit by a strong earthquake with
the strength of 5.5 on the Richter scale. Already after Zagreb earthquake a great need for
spatial interpretation of the event and its aftermath has been recognized. Therefore, after
the earthquake in Petrinja, a quick reaction of geodetic experts followed, using modern
satellite and geoinformation (GI) technologies to provide information on the aftermath of
the earthquake. In a few days GIS applications have been developed for delivery of help
to endangered citizens and to record damages, as well as information on the earthquake
scattering and ground movements in the epicenter area. Synergy of different methods and
fast reaction, i.e. quality information and applications in great helped the organization of
crisis management, information to services and citizens, registration of damages and
reconstruction planning.
This paper presents an overview of the systems, sensors and data used, their processing
and the results obtained, i.e., the applications developed for crisis management purposes
are presented. The results of soil displacement obtained using the data of permanent GNSS
stations processed by the authors of this paper are particularly emphasized, showing that
in Sisak there was a horizontal displacement of about 5.5 cm and a shrug of about 2 cm. |
