Hi Barry. Could you give a location for your question? I know of a couple of areas that seem to have a mix of deep and shallow quakes from time to time. Not sure if that is what you’re looking for though.

Deep quakes and I mean really deep quakes always fascinate me. I know there shouldn’t be any there, but they have them never the less. There are a couple of theories about them. One has to do with “olivine” which is rock, but of course at the depth the quake occurs they aren’t rocks in the sense of the word. If I can find the link in my program I will post it. Take Care…Don in creepy town