Experts are cautiously warning that Monday morning's powerful earthquake in Osaka and surrounding areas could be a sign that greater seismic activity is due in western Japan in the near future.
While details of the fault movements behind the fatal magnitude 6.1 quake have yet to be determined, the inland temblor occurred at a depth of about 13 km, registered as a lower 6 on the Japanese seismic intensity scale to 7, and struck in an area where active faults are concentrated, experts say.
"The quake was shallow, so there is a possibility that it has something to do with the active faults, but a magnitude 6 class quake itself is not big enough to have been caused directly by an active fault," explained Yasuhiro Suzuki, a professor at Nagoya University's Disaster Mitigation Research Center.