usgs doesn't report everything, in fact they are the least reliable agency for earthquake reporting. even german stations are better.  if you see larger quakes you look in between them for the next one, and you also look at emf infrastructure, drill points, and faults for stop offs for the waves. a deep 5 comes up as a shallow 6. and most of the quakes on the west coast are actually man made stress points (emf infra, drill points). the quakes always start in the west pacific and move out across the world from there. antipodal quakes are also well known above mag 6-7. the ones you see on the west coast and in tx are man made stressors from a smaller wave set from the west pacific. a separate guy who is nowhere near as accurate and harrassed by glownigs is frank hoogerbeets, but he is moderately accurate given his models are solely astrological.
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