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To: Strategerist

Arrgh - I can’t type anymore. The San Andreas ends at the Triple Junction. More info here:

http://woodshole.er.usgs.gov/operations/obs/rmobs_pub/html/mendocino.html


44 posted on 01/09/2010 4:56:29 PM PST by Strategerist
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To: Strategerist
From your link:

There are no islands offshore of the California coast at the MTJ. Thus, earthquake location accuracy rapidly degrades as the quakes occur farther from shore because of the one-sided seismic network station geometry. Depths of quakes west of 124º40'W (approximately 50km offshore) are unreliable except for the larger (M>3.5) quakes for which moment tensor inversions can resolve the depth. Likewise, the location accuracy in the direction perpendicular to the coast degrades with distance offshore. The addition of Ocean Bottom Seismometers (OBS) would greatly improve the ability of the NCSN and BSL to understand the seismotectonics of the MTJ following significant quakes. Improved understanding of the rupture mechanics of a subduction zone quake would enable seismologists and hydrodynamicists to more realistically forecast onshore shaking levels and tsunamis. OBS recordings with extended dynamic range and frequency response could possibly reveal the generation mechanics of slow, tsunami quakes. Near-field recordings of offshore earthquakes would greatly improve depth estimates of aftershock sequences and confirm stress transfer models in a region with significant seismic risk.

There are several earthquake scenarios that could warrant a mobilization of the OBS systems. a) M>6.5 quake on the Gorda-North America subduction zone (”G-NA” polygon), b) M>6.5 quake on the Mendocino fault east of longitude 126ºW (”G-P” polygon), and c) M>6 quake on the SAF north of Point Arena (”P-NA” polygon). Deployments within 3 days of such an event are highly desirable due to the unpredictable aftershock decay rate.

There are several harbors along the coast that would provide a base where vessels could be hired to deploy the instruments. Humboldt Bay (Arcata and Eureka) provides the best facilities in the vicinity of the MTJ. There are harbor facilities north of Humboldt Bay at Trinidad and Crescent City. The principal harbors south of the MTJ, which would be more suitable for responding to quakes on the offshore section of the SAF, are at Shelter Cove and Fort Bragg.”

Sounds like your source is asking for more (tax-payer) more of your tax-payer money for his Ocean Bottom Seismographs.

84 posted on 01/09/2010 5:10:16 PM PST by Robert A Cook PE (I can only donate monthly, but socialists' ABBCNNBCBS continue to lie every day!)
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