Using new techniques developed at UCLA and the University of Texas in Austin, Schmitt has found evidence that a chain of small volcanoes, known as the Salton Buttes located at the edge of the Salton Sea, has erupted much more recently than previously thought. This data will redefine Southern California as volcanically active.

http://today.ucla.edu/portal/ut/new-research-redefines-southern-239985.aspx