A pair of earthquakes rattled the South Bay Tuesday night, in an area notorious for seismic restlessness, according to the U.S. Geological Survey.  A 3.9 magnitude quake, the stronger of the two temblors, struck at 10:32 p.m. about 5 miles east-northeast of Alum Rock at a depth of about 5.5 miles, the USGS reported. An earlier quake — a 3.1 — hit at 7:19 p.m. about 5.6 miles east-northeast of San Martin at a

depth of about 7.5 miles, the USGS said. There were no immediate reports of injuries or damage. Dave Freund of Los Gatos felt “a quick, small jolt on Lexington Reservoir.” “A good shaker,” said Sanjay Khandelwal of Los Gatos. “My daughter felt it as well. She sleeps in a bunk bed and felt it move.”  READ MORE