3.5-magnitude earthquake shakes Los Angeles and Southern California, geologists say

A 3.5-magnitude earthquake shook Los Angeles on Wednesday morning, the U.S. Geological Survey reported.

The quake, about 12-mile deep, hit Willowbrook, California, about 13 miles south of Los Angeles, according to USGS.

Dozens of people reported feeling the tremor on social media. Hundreds of people also reported to USGS that they felt the quake, some more than 30 miles away.

Magnitude measures the energy released at the source of the earthquake, the U.S. Geological Survey says. It replaces the old Richter scale.

Quakes between 2.5 and 5.4 magnitude are often felt but rarely cause much damage, according to Michigan Tech.