Free Republic
Browse · Search
News/Activism
Topics · Post Article

Skip to comments.

Tremors rock earth deep beneath San Andreas Fault - Puzzling vibrations baffle researchers
SF Chronicle ^ | December 10, 2004 | David Perlman

Posted on 12/10/2004 8:59:17 AM PST by NYer

Mysterious tremors deep beneath the San Andreas Fault near the quake-prone town of Parkfield are shaking the earth's brittle crust, far below the region where earthquakes normally strike -- and scientists say they can't understand what's happening or what the motions mean.

Seismic researchers are monitoring the strange vibrations closely. But whether the faint underground tremors -- termed "chatter" by some seismologists -- portend an increased likelihood of a major quake in the area is an unsolved puzzle.

Robert Nadeau, a geophysicist at the UC Berkeley Seismological Laboratory, charted more than 110 of the faint vibrations since they were first detected by the lab's High Resolution Seismic Network in Parkfield three years ago. What concerns Nadeau and his colleagues is that the epicenter of the great 1857 Fort Tejon earthquake, whose magnitude has been estimated at 7.8 to 8, was located almost exactly where the deep tremors are now occurring -- beneath the San Luis Obispo County village of Cholame, some 17 miles south of Parkfield.

The episodes of chatter last from four to 20 minutes and are being recorded from as deep as 40 miles beneath the surface -- up to four times the depth of normal earthquakes, which originate in what scientists call the "seismogenic zone." That zone reaches no deeper than 9 or 10 miles below the Earth's surface.

(Excerpt) Read more at sfgate.com ...


TOPICS: Front Page News; Miscellaneous; News/Current Events; US: California
KEYWORDS: earthquake; earthquakes; geology; geophysics; sanandreas; sanandreasfault; tremors
Navigation: use the links below to view more comments.
first previous 1-2021-4041-6061-8081-96 next last
To: Indie

How is it......40 replies and not a word about Michael Moore.


41 posted on 12/10/2004 9:50:30 AM PST by OldFriend (PRAY FOR MAJ. TAMMY DUCKWORTH)
[ Post Reply | Private Reply | To 40 | View Replies]

To: OldFriend

See #10


42 posted on 12/10/2004 9:52:56 AM PST by adaven
[ Post Reply | Private Reply | To 41 | View Replies]

To: Strategerist
The San Andreas is a transform fault and has shallower quakes than subduction zones like Cascadia, West coast of South America, etc. 40 miles is unusual for the San Andreas but not world wide. Deepest quakes are about 400 miles deep.

Wow! You're smart, informed and sane! Go away from this place! I want to play with my tin-foil and don' need no stinkin' "logic" and "facts" gettin' in the way!

43 posted on 12/10/2004 9:54:03 AM PST by Marie (~shhhhh...~ The liberals are sleeping....)
[ Post Reply | Private Reply | To 23 | View Replies]

To: TommyDale

Hmm - what about the salt water intrusion? Are you referring to the wells in Monterey? Please expand for dolts.


44 posted on 12/10/2004 9:54:31 AM PST by little jeremiah (What would happen if everyone decided their own "right and wrong"?)
[ Post Reply | Private Reply | To 4 | View Replies]

To: NYer

45 posted on 12/10/2004 9:55:48 AM PST by Constitutionalist Conservative (Have you visited http://blog.c-pol.com?)
[ Post Reply | Private Reply | To 1 | View Replies]

To: OldFriend

Ha! See post #10 and pay attention lil' FReeper! ;-)


46 posted on 12/10/2004 9:56:25 AM PST by Marie (~shhhhh...~ The liberals are sleeping....)
[ Post Reply | Private Reply | To 41 | View Replies]

To: StoneGiant

Walken was so good in the series, Sarah Plain and Tall. I really loved him. But in other movies, he is really weird!


47 posted on 12/10/2004 9:57:46 AM PST by Marysecretary (Thank you, Lord, for FOUR MORE YEARS!!!)
[ Post Reply | Private Reply | To 11 | View Replies]

To: NYer
Puzzling vibrations baffle researchers

Doncha know?! Those are the Beach Boys' GOOD Vibrations!

48 posted on 12/10/2004 9:58:46 AM PST by NotJustAnotherPrettyFace (Michael <a href = "http://www.michaelmoore.com/" title="Miserable Failure">"Miserable Failure"</a>)
[ Post Reply | Private Reply | To 1 | View Replies]

To: MineralMan
Interesting. Since I used to live near there, I'm interested in activity in that area.

Same here. Sold a home in Paso Robles in 1976 for $42000 that I bought in 1975 for $30000. If only I could have held on to it for 20 more years..

49 posted on 12/10/2004 9:58:58 AM PST by TruthWillWin
[ Post Reply | Private Reply | To 7 | View Replies]

To: OldFriend

It's arafart, all those muslimes, and the ragged assortment in hell's domain all having a brawl over those 72 virgin creatures.


50 posted on 12/10/2004 10:00:44 AM PST by mommadooo3
[ Post Reply | Private Reply | To 41 | View Replies]

To: NYer

If there's a quake and a forest fire at the same time, the movie could be entitled "Shake and Bake."


51 posted on 12/10/2004 10:01:49 AM PST by Doctor Stochastic (Vegetabilisch = chaotisch is der Charakter der Modernen. - Friedrich Schlegel)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Frank_Discussion

No. Gore-zilla!


52 posted on 12/10/2004 10:02:48 AM PST by Redleg Duke (Pass Tort Reform Now! Make the bottom clean for the catfish!)
[ Post Reply | Private Reply | To 2 | View Replies]

To: NYer

"Are you still in CA or have you left the state?

"

I moved to Minnesota this past Summer. I used to live about 40 air miles from Parkfield, though.


53 posted on 12/10/2004 10:03:44 AM PST by MineralMan (godless atheist)
[ Post Reply | Private Reply | To 35 | View Replies]

To: NYer

40 miles beneath the surface. That's in the mantle, isn't it? If so, that means possibly hot, squishy rock? Would that account for the "strange vibrations", that the waves were passing through less than solid rock?


54 posted on 12/10/2004 10:04:17 AM PST by mewzilla
[ Post Reply | Private Reply | To 1 | View Replies]

To: MineralMan
I like to be informed of these things too. I also used to live on the San Andreas Fault Line (Huntington Beach) and experienced a few earthquakes out there. Nothing major, but enough to shake you up a little. One of these days Fountain Valley will be Ocean Front property.
55 posted on 12/10/2004 10:05:10 AM PST by Ginifer
[ Post Reply | Private Reply | To 7 | View Replies]

To: All

I've got just one word for all your Californians.............NEBRASKA


56 posted on 12/10/2004 10:05:55 AM PST by Chuck54 (Democrats - Lights are on, nobody's home!)
[ Post Reply | Private Reply | To 54 | View Replies]

To: TruthWillWin

"Same here. Sold a home in Paso Robles in 1976 for $42000 that I bought in 1975 for $30000. If only I could have held on to it for 20 more years.."

Yup. I bought my house on the coast in SLO county in 1974 for $20,000. Sold it in June for $337,000. Moved to MN and bought a house twice its size for $174,000. Fair exchange.


57 posted on 12/10/2004 10:06:07 AM PST by MineralMan (godless atheist)
[ Post Reply | Private Reply | To 49 | View Replies]

Comment #58 Removed by Moderator

To: NYer
Mysterious tremors deep beneath the San Andreas Fault near the quake-prone town of Parkfield are shaking the earth's brittle crust, far below the region where earthquakes normally strike -- and scientists say they can't understand what's happening or what the motions mean


59 posted on 12/10/2004 10:09:30 AM PST by theFIRMbss
[ Post Reply | Private Reply | To 1 | View Replies]

To: NYer

No worry...It's just another Nancy Pelosi orgasm....


60 posted on 12/10/2004 10:11:38 AM PST by Route101
[ Post Reply | Private Reply | To 1 | View Replies]


Navigation: use the links below to view more comments.
first previous 1-2021-4041-6061-8081-96 next last

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
News/Activism
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson