PASADENA, Calif. (AP) - The earthquake that rocked Southern California over the weekend may have triggered several moderate quakes near the San Andreas Fault, seismologists said Monday. The so-called Hector Mine earthquake tore a 25-mile-long gash from a dry lake through the Mojave Desert, displacing dirt roads and creek beds. Scientists upgraded the quake's magnitude from 7.0 to 7.1 Monday - a 25% increase in shaking. Saturday's temblor, which struck at 2:46 a.m. in a sparsely populated stretch of desert, caused minor injuries on an Amtrak train that derailed. Within hours of the quake, some seismologists were alarmed by a series of earthquakes as powerful as 4.0 that struck 120 miles away near the Salton Sea, a few miles from the massive San Andreas Fault.