Late Night Musing
Posted by Don in Hollister on February 02, 2006 at 03:27:15:

Hi All. Every time I look at the California/Nevada quake map and see those little quakes in the western part of Nevada it makes me think of someone drawing a line and telling the quakes not to cross this line. There are of course quakes that do, but they are few and far between.

I look at those quakes and wonder if they are a part of the Walker Lane Belt which of course that isn’t possible unless of course the Walker Lane Belt is much wider then what is currently thought. I don’t suppose it really matters anyway as the quakes are going to occur regardless of whether they are in the Walker Lane Belt or not.

I’ve seen times when there were only a couple of quakes and I have seen times when there were a lot of quakes. It makes me wonder if they are the weak links in a chain and if so, what happens when there are no more weak links. Would that mean we could have another September 12, 1994 Double Spring Flat quake. The earthquake was centered 12 miles SSE of Gardnerville near Double Spring Flat, and had a local Richter magnitude of M=6.0 or could we have another Dixie Valley quake? Two strong earthquakes ripped west-central Nevada on December 16, 1954. The first quake of the Dixie Valley-Fairview Peak series struck at 3:07 a.m. and measured M=7.2

The second quake occurred about 4 minutes later and measured M=6.8. Surface fault ruptures occurred along six different faults that defined a complex north-trending 100 km long and 15 km wide zone. Both vertical and horizontal (right-lateral) displacements were measured with maximum offsets of over 12 feet.

Okay, so there hasn’t been enough time for stress to build to cause a quake or quakes near the same magnitude to occur again. How about if we moved the quake further to the east into Utah? Now there’s a place we could have a large quake. It has been a long time since the last one. Okay so maybe Utah only gets a large quake about once every 500 years and it has been that long since the last one.

Lets go west then into the Owens Valley area. The last really big quake in that area was in 1872. That makes it more then 130 years since the last big quake in that area. In 1872, a major earthquake struck the Owens Valley, demolishing the town of Lone Pine, 80 miles south of Mono County. Estimated to have been M=7.6, it killed many of the town’s inhabitants when their adobe houses collapsed. They didn’t have building codes in those days.

The most recent strong earthquake, a M=6.4, rocked Chalfant Valley in southeastern Mono County in 1986. That earthquake caused moderate damage but, fortunately, no fatalities. Spent a night in Chalfant. Slept in the back of my Explorer. No room at the hotel. Come to think of there wasn’t a hotel there. No motel either.

Talked to some of the residents there who showed me where they said they saw dust shooting up into the air during the quake. I asked them what they meant by shooting up into the air. They demonstrated to me by saying whoosh and then throwing a handful of dust into the air. I asked them if they heard anything and they all said they heard a rumbling noise and of course things falling and breaking. I got the impression that was one of the more exciting things that happen around there. The other exciting time was when they though Long Valley was going to erupt and blow them off the face of the earth, or bury them, which ever came first.

Okay so maybe it hasn’t been long enough for another Owens Valley type of quake. Come to think of it do we really know how long it takes between large quakes? I sure don’t. Take Care…Don in creepy town