Hi Michael,

The event 9 miles NE of Boron appears to me to be on/near the Lockhart Fault.
There have been several quakes in the last 6 months or so in an area about 6 miles N/S by about 4 miles E/W in that area. Someone might like to plot them on a map. They also vary from the surface down to a few kilometers.

A look at Google Earth and Terra Server don`t show any obvious mining operations in the area.

Byron