[Strategerist]

The episodes of chatter last from four to 20 minutes and are being recorded from as deep as 40 miles beneath the surface -- up to four times the depth of normal earthquakes, which originate in what scientists call the "seismogenic zone." That zone reaches no deeper than 9 or 10 miles below the Earth's surface.

Another bad MSM science article....

The San Andreas is a transform fault and has shallower quakes than subduction zones like Cascadia, West coast of South America, etc. 40 miles is unusual for the San Andreas but not world wide. Deepest quakes are about 400 miles deep.

[Strategerist]

Well, on reviewing the whole article at the link, it's a case of a poorly organized and worded article; they do eventually explain the difference between the San Andreas and subduction faults, and that deep quakes occur on subduction faults, but the opening doesn't make clear the depth of the tremor are unusual for the San Andreas, not for faults world wide.

[Marie]

The San Andreas is a transform fault and has shallower quakes than subduction zones like Cascadia, West coast of South America, etc. 40 miles is unusual for the San Andreas but not world wide. Deepest quakes are about 400 miles deep.

Wow! You're smart, informed and sane! Go away from this place! I want to play with my tin-foil and don' need no stinkin' "logic" and "facts" gettin' in the way!