In a message dated 9/17/2006 6:25:22 PM Mountain Standard Time, Goh83642 at wmconnect.com writes: Is there a correlation to a geyser in eruption that would last 30 minutes and cause the seismograph to record such an eruption? Actually on this, a further thought. I do not know the physical location of the Norris instrument, but... On tour on Thursday (and again on Friday) I saw that a rather large water pump had been installed at the Gibbon River, next to the road crossing east of Norris Junction. A large hose was draped across the meadow, evidently headed toward the new sewage treatment facility. Perhaps it is this pump that produced the helicorder signal? Scott Bryan -------------- next part -------------- An HTML attachment was scrubbed... URL: </geyser-list/attachments/20060917/a6a39e5f/attachment.html>