The 1906 earthquake in California, about 5:12 am on April 18, was before the Richter scale, but scientists estimate it would rank as a 7.8. As much as 90% of the damage in San Francisco was from fires caused by cracked gas pipes. San Francisco burned for three days and nights.
The December 26, 2004 Indian Ocean earthquake located off the west coast of Sumatra, Indonesia lasted nearly 10 minutes—the longest on record.