Summer 2011 ETS

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Blog for ETS of Summer, 2011 (Three Months Early ????)
Deep Tremor News: Aug, 2011 - ....         (why so early))

Array of Array (AofA) trying to go again....... continued

This blog is quickly being thrown together now that this next ETS seems to be starting early. We will update this page with information, observations and some thoughts on what is going on in Cascadia deep tremor during the summer and fall of 2011. The AofA experiment was a very successfull experiment recording the ETS of summer, 2010 providing data for several research papers and a PhD dissertation.

There were nine arrays installed of ~10 continuous, three-component stations each starting in summer of 2009 through fall of 2010. Because of power limitations, the need for dataloggers for other PASSCAL experiments elsewhere and the amount of effort to service this many stations most arrays have been shut down for long periods when ETS was not expected. The 2011 ETS was expected to start in late October or early Novemeber based on the normal inter-ETS of 14-15 months. The arrays were to be restarted in early to mid Octorber.... BUT ------

On July 23 a tremor burst near Olympia (which we all thought was a typical short-lived inter-ETS tremor burst) just kept going. We waited for the tremor to die out, but it didn't. First it moved a bit south and then east and then hovered near Olympia until early August. We kept thinking it couldn't be a real ETS. It was too soon and seemed to start way too slowly. Besides much of the tremor was not as strong as we were used to seeing during previous ETS. But, after more than a week of significant tremor we started to panic and contacted the PASSCAL instrument center to see about getting some dataloggers back in the field sooner than originally requested.
PASSCAL came through and shipped us 48 datalogers on very short notice. THANK YOU PASSCAL STAFF! On Aug 5, when the tremor started clearly moving slowly north we double paniced and made preparations to head to the field ASAP.

Information will be posted on this page (latest at the top) and references to figures from time to time.

NEWS (latest at the top)