http://quake.wr.usgs.gov/recenteqs/FaultMaps/115-34_eqs.htm
Holy quake! Magma movement? A new volcano? They seem pretty shallow.
The area around the Salton Sea has repeated earthquake swarms, and that location had large swarms in 2003 and 2004.
They typically don't mean much.
There are actually some small volcanoes in the area, last erupted 16,000 years ago, which is real recent in geology, but none of these swarms previously have had anything to do with volcanism.