Hi All. I thought you might be a little bit interested in this. The first list is of quakes inside a 12-mile radius of the Geysers area. As you can see there are 14 quakes there. The first 6 occurred over a 45-year period with the last 8 of them over a 4-year period. The second list of quakes is inside a 25-mile radius. The marked increase there appears to be the two Santa Rosa quakes and their aftershocks. You will note the quite period between 1969 and 1980.

Starting in 1980 the number of M>4.0+ quakes started to increase. Slow at the start, but did start to increase never the less for a total of 10 quakes over a 15 year period. This however is still less in the number of quakes per year then in the last 4 years for the time period from 2000 to 2004. The Bennett Valley quake isn't in this list, but it wouldn't take much to get it in. There is also the Yountville quake, but I didn’t include it as I feel it is to far removed from the immediate Bay Area. To the best of my knowledge no fault has ever been identified as the cause of this quake as there was no surface rupture for this quake.

The quakes appear to be associated with 2 fault systems, possible 3. These would be the Maacama Fault, The Healdsburg/Rodgers Creek Fault and the Mount Konocti Fault Zone.

The quakes that caught the interest of a lot of people were the 3 quakes just to the SE of Cloverdale in Jan. of 2000 that appear to be associated with the Maacama Fault. However, these earthquakes are not on the actual Maacama Fault. Instead they form a north-south line and the motion recorded during these events suggests that each occurred on a north-south fault. Thus, it was conclude that they occurred on a minor north-south fault that is part of the larger and complex Maacama Fault system. There is of course the 4th quake that occurred in July of 2003 about 5-miles south of the Jan. 2000 quakes. This quake is most likely associated with the previous 3 quakes so it makes me wonder what might be in store for future quakes in this area. Take Care…Don in creepy town

1955/05/07 11:50:39.00 38.9300 -122.8700 4.60 ML BK
1955/05/07 14:56:15.00 38.9300 -122.8700 4.20 ML BK
1982/05/29 13:02:24.61 38.8010 -122.8222 2.29 4.65 Md 48 25 3 0.07 NC 1074871
1990/08/14 19:05:12.64 38.8247 -122.7922 3.03 4.08 Md 46 36 2 0.08 NC 20092005
1992/09/19 23:04:46.83 38.8598 -122.7915 4.16 4.30 Md 47 34 6 0.08 NC 316220
1995/09/04 14:16:17.66 38.6832 -122.7428 7.69 4.46 Md 52 42 3 0.08 NC 30082729
2000/01/10 21:41:27.13 38.7565 -122.9147 6.82 4.28 ML 48 49 9 0.13 NC 21076620
2000/01/11 14:19:52.07 38.7680 -122.9137 6.81 4.34 ML 42 49 6 0.12 NC 21076750
2000/01/18 23:26:01.31 38.7515 -122.9135 7.65 4.22 ML 52 35 6 0.13 NC 21078341
2000/12/08 07:41:11.43 38.7818 -122.7667 4.06 4.15 ML 50 30 4 0.10 NC 21137862
2003/05/20 16:50:41.78 38.8018 -122.8047 1.27 4.05 Mw 46 30 1 0.06 NC 30225804
2003/07/30 04:50:06.36 38.6808 -122.9117 5.10 4.01 ML 42 44 9 0.11 NC 30226086
2003/08/03 12:00:52.83 38.7978 -122.7680 1.75 4.20 Mw 37 36 3 0.06 NC 30226108
2004/02/18 20:37:46.46 38.8340 -122.7652 3.57 4.40 Mw 45 41 4 0.14 NC 40153486
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1954/11/10 18:07:21.00 39.0700 -123.0300 4.40 ML BK
1955/05/07 11:50:39.00 38.9300 -122.8700 4.60 ML BK
1955/05/07 14:56:15.00 38.9300 -122.8700 4.20 ML BK
1956/04/05 04:29:13.00 38.5300 -122.5200 4.40 ML BK
1956/04/05 04:29:32.00 38.5300 -122.5200 4.20 ML BK
1969/10/02 04:56:45.33 38.4963 -122.6638 0.07 5.27 Md 39 104 52 0.20 NC -1003132
1969/10/02 06:19:56.33 38.4515 -122.7522 4.16 5.22 Md 52 170 58 0.20 NC -1003135
1969/10/02 12:27:04.65 38.5085 -122.6872 0.02 4.52 Md 52 106 53 0.23 NC -1003137
1969/10/06 14:28:06.96 38.4753 -122.6987 4.50 4.28 Md 18 53 1 0.02 NC -1003160
1980/12/12 14:57:08.05 38.9455 -122.6815 2.40 4.03 Md 32 73 1 0.08 NC -1058048
1982/05/29 13:02:24.61 38.8010 -122.8222 2.29 4.65 Md 48 25 3 0.07 NC -1074871
1984/09/24 14:40:22.00 38.9777 -122.4900 5.20 4.20 Md 6 255 30 0.40 NC -1120659
1985/03/16 05:26:13.22 38.8872 -122.9933 15.47 4.10 Md 5 321 19 0.09 NC -1126652
1985/07/03 10:24:01.03 38.9325 -122.9712 5.00 4.25 Md 4 119 13 0.16 NC -1129446
1990/08/14 19:05:12.64 38.8247 -122.7922 3.03 4.08 Md 46 36 2 0.08 NC 20092005
1992/09/19 23:04:46.83 38.8598 -122.7915 4.16 4.30 Md 47 34 6 0.08 NC 316220
1994/01/17 14:46:11.98 38.8050 -122.4450 11.21 4.06 Md 69 101 0 0.16 NC 391405
1995/02/28 23:09:46.77 38.9307 -122.6243 5.73 4.00 Md 46 67 4 0.09 NC 30068952
1995/09/04 14:16:17.66 38.6832 -122.7428 7.69 4.46 Md 52 42 3 0.08 NC 30082729
2000/01/10 21:41:27.13 38.7565 -122.9147 6.82 4.28 ML 48 49 9 0.13 NC 21076620
2000/01/11 14:19:52.07 38.7680 -122.9137 6.81 4.34 ML 42 49 6 0.12 NC 21076750
2000/01/18 23:26:01.31 38.7515 -122.9135 7.65 4.22 ML 52 35 6 0.13 NC 21078341
2000/12/08 07:41:11.43 38.7818 -122.7667 4.06 4.15 ML 50 30 4 0.10 NC 21137862
2003/05/20 16:50:41.78 38.8018 -122.8047 1.27 4.05 Mw 46 30 1 0.06 NC 30225804
2003/05/25 07:09:33.65 38.4578 -122.6987 5.40 4.32 ML 68 52 2 0.17 NC 30225889
2003/07/30 04:50:06.36 38.6808 -122.9117 5.10 4.01 ML 42 44 9 0.11 NC 30226086
2003/08/03 12:00:52.83 38.7978 -122.7680 1.75 4.20 Mw 37 36 3 0.06 NC 30226108
2004/02/18 20:37:46.46 38.8340 -122.7652 3.57 4.40 Mw 45 41 4 0.14 NC 40153486