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Comment: 23:17 - 24:30 (01:13)
Source: Annenberg/CPB Resources - Earth Revealed - 9. Earthquakes
Keywords: earthquake, "Cathleen Aviles", fault, magnitude, "fault zone"
Our transcription: Tiny earthquakes are common occurrences along most active faults, but shortly before a large quake, the frequency and distribution of small shocks may change.
Being the person who looks at the seismicity, I'm expecting to see some changes in the patterns of the earthquake.
The earthquakes occur in the fault zone in a fairly complicated manner.
Some places the activity's shallow; some places the activity's deep.
As we get more detailed information about the fault zone, we see certain knots or clusters that are active.
What we're seeing, what we're expecting to see is that the larger earthquakes will start at magnitude 2's, 2.5's, 3's, and they'll start migrating down the fault zone towards the area that will fail first in that earthquake.
This is the pattern that's been seen in '34 and in '66 and that we're keeping a very close eye on the activity to see if that kind of activity occurs again.
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