Hi All. On 09/21/1993 there were two M>6.0 quakes in the Klamath Falls, Oregon area. There appears to have been one foreshock 12 minutes before the first M>6.0 quake at 42.31N/122.01W at 03:28AM. The second M>6.0 occurred at 42.36N/122.04W at 05:45AM.

The aftershocks to these quakes give an indication that the fault ruptured towards the south. The most recent quake appears to be inside the area of the aftershocks. I’m a little hesitatent to say this quake was an aftershock of the two M>6.0 quakes as it appears the aftershocks ended in Dec. of 1994. There have been a total of 5 quakes (M>2.7 to M>3.4. NEIC doesn’t catalog quakes smaller then M>2.0) in the general area since 1995 so that makes it rather doubtful that this quake is a foreshock to something larger. The MTS indicates the 1993 quakes were normal faulting with down slip component.

The M>5.4 quake off the coast of Oregon occurred along a strike-slip fault inside the Gorda Plate. Past MTS indicate pure strike-slip.

These quakes along with the most recent quakes of the coast of Punta Gorda don’t indicate that something much larger is about to occur. However by the same token they don’t reduce the potential for something much larger. There would have to be 100s of thousands quakes of the most recent magnitudes to reduce the probability of an M>9.0 along the Cascadia Subduction Zone. Take Care…Don in creepy town