Hi All. Here is a list of past quakes within a 10-mile radius of the most recent swarm of quakes north of Long Valley Caldera. I looked for all quakes from M>1.0 with no max. I decided to use only those that were M>4.0 and larger to keep the bandwidth used to a minimum.

There are 40 some odd faults in the area. A more correct description would be that the ground is fractured in the area in that it�s a small area. There are 24 cinder cones and other types of volcanoes in those faults. No history is given for the eruption periods of them other then 2 million years ago to historic. I�m not sure if I can find one either.

There have been other swarms of quakes in the area with the largest in 1980 till the most recent one. The one in 1980 was a couple of months after the four M>6.0+ quake occurred in and near Long Valley Caldera with two of those quakes being non-double couple meaning they were caused by volcanic activity of some kind Anyway they were caused by something other then tectonic. This most recent swarm isn�t in the area of increase in activity in the Long Valley Caldera. I can�t say the same thing for the swarm in 1980 meaning I can't say that the swarm wasn't related to the increase in activity at Long Valley.

It has been reported that the movement of magma could have caused this most recent swarm of quakes. Not knowing the source of that report I would take that with a grain of salt.

In addition to the most recent swarm there is a second small number of quakes located to the east around 38.250N/117.814W. There aren�t very many faults shown in this area, but there are 32 cinder cones and assorted volcanoes shown there. This small cluster of quakes is in the eastern most section of the cinder cones.

Most of the cinder cones seem to be following a NE/SW track with maybe no more then a couple of miles separating them. It would be interesting to know what the sequence in eruptions were starting with the first and when it ended with the last one. Most were active in Pleistocene time (11,000 to 2 million years ago), some in Holocene (10,000 years) a few are historic.

I have a couple of e-mails floating around asking if some of the quakes were non-double couple. Hope I get an answer other then �I don�t know.� Of course I know it will take some time to analyze those quakes so I will just have to be patient. Take Care�Don in creepy town

catalog=ANSS
start_time=1898/01/01,00:00:00
end_time=2004/09/20,04:11:02
minimum_magnitude=4.0
maximum_magnitude=10
event_type=E
delta=0 km to 16 km from (37.993,-118.719)
Date Time Lat Lon Depth Mag Magt Nst Gap Clo RMS SRC Event ID
----------------------------------------------------------------------------------------------
1937/03/09 15:41:37.94 37.8757 -118.7155 10.00 4.00 ML 0 0.00 CI ��
1951/10/01 18:19:59.00 38.0000 -118.8333 0.00 4.00 ML 0 0.00 CI ��
1971/02/20 12:57:44.00 37.9583 -118.6353 8.00 4.00 ML 0 0.00 CI 0
1977/10/10 19:26:04.90 38.0220 -118.7530 6.00 4.00 un 24 0.00 BRK 197710104010
1980/06/29 07:46:14.10 37.9750 -118.6700 15.00 5.00 un 31 0.00 BRK 198006294012
1980/06/30 10:22:00.91 38.0088 -118.6763 6.62 4.11 Md 6 90 10 0.06 NC -1054130
1980/06/30 10:23:01.50 38.0050 -118.7070 5.00 4.00 un 12 0.00 BRK 198006304011
1980/09/06 05:31:03.30 38.0750 -118.5770 5.00 4.00 un 15 0.00 BRK 198009064003
1980/09/06 07:27:52.10 38.0680 -118.5720 5.00 4.60 un 23 0.00 BRK 198009064004
1980/09/07 01:30:42.70 38.0480 -118.5580 14.00 5.10 un 50 0.00 BRK 198009074001
1980/09/07 04:36:38.30 38.0330 -118.5780 15.00 5.00 Ms 104 0.00 BRK 198009074002
1980/09/07 06:47:09.79 38.0633 -118.5943 11.06 4.63 Md 7 95 16 0.09 NC -1055547
1980/09/07 06:48:09.89 38.0645 -118.5963 10.42 4.90 Md 12 110 16 0.06 NC -1055548
1980/09/08 04:26:19.90 38.0280 -118.5820 13.00 4.60 un 18 0.00 BRK 198009084003
1980/09/16 04:24:41.10 38.0120 -118.5570 14.00 4.60 un 20 0.00 BRK 198009164004
1980/11/11 10:19:02.90 38.0080 -118.6000 5.00 4.80 un 22 0.00 BRK 198011114005
1980/11/11 10:33:51.20 38.0330 -118.5930 9.00 4.00 un 10 0.00 BRK 198011114006
1981/01/01 18:22:22.40 38.0530 -118.5700 5.00 4.20 un 10 0.00 BRK 198101014013
1981/05/07 01:02:37.90 37.9870 -118.5570 15.00 4.50 un 27 0.00 BRK 198105074001
1981/09/12 18:12:58.60 38.0600 -118.5900 16.00 4.30 un 19 0.00 BRK 198109124030
1983/12/07 22:15:56.15 38.0283 -118.7187 1.11 4.00 Mc 20 65 6 0.17 NN
1992/10/10 17:54:51.12 37.9938 -118.5773 7.97 4.18 Mc 76 47 8 0.12 NN
1997/04/14 11:20:53.89 38.0712 -118.7328 8.37 4.17 Mc 40 46 3 0.08 NN
2000/01/19 11:11:02.96 38.0475 -118.7286 9.22 4.41 ML 32 0.14 NN
2000/01/20 10:04:56.11 38.0494 -118.7298 9.17 4.21 ML 46 0.18 NN
2000/01/21 10:18:34.15 38.0496 -118.7292 8.88 5.03 ML 40 0.15 NN
2004/09/18 07:07:10.56 38.0063 -118.6770 5.43 4.00 ML 42 73 5 0.08 NC 51146286
2004/09/18 07:08:00.00 37.9900 -118.6920 1.50 4.10 ML 49 0.00 NC 200409181003
2004/09/18 23:02:17.80 38.0090 -118.6792 7.58 5.55 ML 48 71 10 0.08 NC 51146343
2004/09/18 23:43:31.64 38.0092 -118.6692 11.11 5.34 ML 20 72 14 0.07 NC 51146383
2004/09/18 23:43:41.79 38.0190 -118.6613 11.24 5.40 ML 51 178 7 0.09 NC 51146384
2004/09/18 23:47:58.51 38.0237 -118.6488 4.33 4.10 ML 50 77 14 0.07 NC 51146385

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