Hi Lowell. It’s still the 27th here on the West Coast. Close enough for Government work. Oh yea. Forgot. You’re no longer with the Government, but then again neither am I.

The Landers Earthquake sequence that started at 4:58 A.M. appears to have occurred on the north-northwest striking Camp Rock-Emerson and Johnson Valley faults. The southern extension of this fault system previously moved during the April 22, 1992, M6.1 earthquake. This quake appears to have been a foreshock to the Landers quake, which in turn triggered the quake at Big Bear.

The focal depth of the Landers event was within one to two miles of the ground surface—much shallower than is typical of California earthquakes. A 43-mile long surface rupture zone begins about 2 miles north of Yucca Valley and extends north-northwest to within approximately 10 miles southeast of Barstow. The observed right-lateral slip was about 10 feet in the Landers area. The maximum observed lateral slip was about 21 feet on the Emerson Fault.

The faulting typically occurred over a zone of 10 to 120 feet across. Vertical offsets of up to four feet accompanied the lateral offsets. It is estimated that about 25% of the surface ruptures occurred along previously unmapped faults.

Scientists are currently studying the possibility that these earthquakes may be related to a future event on the San Andreas Fault. Evidence of stress buildup on the southern San Andreas Fault system in this area has concerned scientists for years. In addition, since 1986 there have been several M5.9 or larger events near this fault. Similar sequences preceded the 1906 M8.3 San Francisco and 1989 M7.1 Loma Prieta earthquakes.

This now brings us to the Bay Area. We have had a moderate quake in Bolinas, Yountville and Bennett Valley. Not to mention the twin M>5.0+ in Santa Rosa in 1969. You told me a long time ago that patterns have a meaning and that I should continue to look for them. I am and I will. Now to learn what those meanings are, or maybe it should be how to interpret them. Take Care…Don in creepy town