[time-nuts] GPS, USGS Early Earthquake Warning

[Brooke Clarke]

Hi Hal:

In the talk there was a slide showing a comparison between ground position calculated from an accelerometer and a real 
time precision GPS.
The Accelerometer is AC coupled and so misses the DC coupled GPS answer that shows the permanent ground movement.
I'm guessing it takes a GPS receiver that has 100 Hz or faster outputs that can be reduced to cm or better position to 
do this.

Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/Clarke4Congress.html


Hal Murray wrote:
>> The quake talk was not on line so I watched the one on Climate Change and
>> it's impact on N. California.  Interesting,  but no human impact data, only
>> wildlife.
> It's up now.
>    http://online.wr.usgs.gov/calendar/2012/apr12.html
>
> For a good time sink, my favorite talk was March 2011:
>    Unraveling the Mystery of Avian Navigation
>    http://online.wr.usgs.gov/calendar/2011/mar11.html
> A little more text back at:
>    http://online.wr.usgs.gov/calendar/2011.html
>
> For anybody in the Silicon Valley area, their open house is May 19-20.  It's kid friendly, both big kids and little kids.  You get to talk to the people who are actually doing the work.  They are happy with geeky questions.
>
> -------------
>
> Back to somewhat time-nutty stuff...
>
> Does anybody understand how they are using GPS and/or have performance numbers?
>
> They don't need the actual position (DC), just the changes in position.  They need it now.  They can't wait for post processing.  I'm not sure how much accuracy they need.  I'd guess in the cm range.
>
> (Maybe I can learn more at the open house.)
>
>
>