Scientists today downgraded the Richter scale magnitude of the earthquake that rocked Southern California on Oct. 1 from 6.1 to 5.9.
"The 6.1 was a preliminary number" and a 5.9 magnitude for the damaging earthquake is now the best estimate, said Kate Hutton, a seismologist at the California Institute of Technology in Pasadena.
Hutton said that analysis of readings recorded by seismograph stations throughout Southern California resulted in the new magnitude, as well as a revised estimate of 5.3 on the Richter scale for the Oct. 4 aftershock that previously had been estimated to have a magnitude of 5.5.
Lucy Jones, a U.S. Geological Survey seismologist, said that Richter scale earthquake magnitudes are defined as the magnitudes recorded in the vicinity of the quake, therefore the agency would have to accept the downgraded magnitude estimates.
The Oct. 1 main shock and the Oct. 4 aftershock caused the deaths of seven people and an estimated $213 million in damage.
Hutton revealed the new magnitude estimates as dozens of scientists met at the University of Southern California to review scientific findings about the earthquakes.