17 January 1995 is a date that every resident of Kobe will never forget. Early in the morning when many people were still sleeping, there was a sudden earthquake measuring 7.2 on the Richter scale. About 250,000 houses collapsed and 6,425 people were killed. Highways collapsed and the economic loss was great. Five years have passed. Now Kobe has been rebuilt from the ruins. The rebuilding of the city cost 12 billion US dollars.
Explain the occurrence of the earthquake in Kobe.
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