SANTIAGO, Dec. 27 (Xinhua) -- Experts identified Thursday at least 23 moderate quakes that hit southern Chile in the past two days as aftershocks of the 8.8-magnitude earthquake in 2010.
According to official reports, starting at 9:37 p.m.(0037 GMT) local time Wednesday night until Thursday noon, 23 earthquakes occurred in Cobquecura, about 420 km southwest of the national capital of Santiago, but only five quakes were felt by local people.
Sergio Barrientos, chief of the Seismology Institute of University of Chile, said it is clear that "epicenter zones of these earthquakes overlapped that of 2010 earthquake. They are aftershocks of Wednesday's 5.2-magnitude main aftershock."
"These are late aftershocks of the 2010 Chile earthquake," said Mario Pardo, seismologist from the University of Chile. The 8.8-magnitude earthquake hit the country on Feb. 27 more than two years ago, with the epicenter located off Cobquecura in Biobio region. The earthquake and subsequent tsunami killed some 500 people and affected about 800,000.
Veronica Pineda, geologist from University of Concepcion, said the seismic activity in this area was normal, although it has increased in the last days.
"We have to remember that after an earthquake such as the one that occurred in 2010, there is always an adjustment process of the plates and this causes seismic activities. We have to get used to this and take preventive measures if needed," said Pineda.
A similar sequence of earthquakes that occurred in November in the same area were also identified as late aftershocks of the 2010 earthquake.
Officials from the National Emergency Office called on the public to get prepared for a possible larger earthquake.