This afternoon (1/6/2009), Wim Kolk, one of Xanterra's guides based out of Mammoth, asked if I'd heard anything about thermal features changing due to the recent earthquakes. I said I hadn't heard, but that there aren't many geyser gazers around to notice. Wim said that on December 26th, late in the morning when he was headed to Old Faithful, that the runoff channels from Indigo Spring (Midway Geyser Basin) were completely dry, with snow on them, but that afternoon, when he was headed back to Mammoth, they were trickling again, and the next day, running as normal. I said there may be a possible relation to the earthquakes, but now looking back over the earthquakes, the swarm started in the afternoon, local time, so perhaps the changes in Indigo's runoff and the quake swarm, share a common trigger. Well, it is a hypothesis, anyway! Kind of hard to test it. The traditional scientific method sometimes doesn't work perfectly for geology. I was off on December 26th, and the Mammoth drivers go past Midway Geyser Basin more often than I do, and they do usually stop there to let their guests take pictures. Karen Low -------------- next part -------------- An HTML attachment was scrubbed... URL: </geyser-list/attachments/20090106/a84c4036/attachment.html>