News from the Field: Day 10--Water Chemistry and Water-Rock Interaction

Today was our chemistry day. We began with a presentation by Dan Dawson, a water chemist (and SNARL's director) on water quality research in Lake Crowley. He demonstrated water sampling techniques in nearby Convict Creek and discussed both scientific and environmental implications of his research. We returned to the dorm for a couple of hours of discussion on the origin and evolution of magmas and on magma-water interaction. On to Casa Diablo for an opportunity to view the products of hydrothermal alteration of volcanic rock. We visited a kaolin mine, an unusual exposure of 'blue chert', a fossil hot spring rich in gold ore. We ended our day with a delightful dip in the boiling waters of the aptly-named Hot Creek. Dinner back at the ranch with the Dawsons, and an early evening--we'll be up at the crack of dawn for...Yosemite Day tomorrow.

May 27th

*Dan Dawson, SNARL's director, explains the background on the Crowley Lake water quality study*
*The group treks out to Convict Creek, for some field measurements, with SNARL's little campus in the background*
*On to Convict Creek, where Dan explains the basics of water sampling technique*
*And measurement of dissolved oxygen...*
*And a topset stream gauge, for measuring stream velocity...*
*Back at SNARL's water chemistry lab, Dan discusses lab assay techniques*
*En route back to the dorm, Neal Solon does battle with the Dawson's kids!*
*Back at the dorm, John leads a discussion on hydrothermal alteration.*
*And Tom McFarland tries his hand at the blackboard*
*In the afternoon, we're back out in the field. The group examines an outcrop of hydrothermally altered lake sediments at Casa Diablo, in Long Valley's resurgent dome*
*Leah French takes some notes while protecting herself from the nasty clay dust!*
*Neal Solon tries out a little taste--the geologist's test for clay*
*John leads a discussion at the kaolin mine, a site of intensive hydrothermal alteration*
*The group examining (or playing with?) the clay at the kaolin mine*
*Laura Dunn works on some kaolin pottery, while Mariel Berger looks on*
*The last stop of the day--the beautiful valley of Hot Creek, with active steam vents visible in the background*
*Is this group fazed by the warning signs? Heck no!*
*Welcomed by the colorful natives, the gang decides to test out the thermal waters of Hot Creek*
*A prime example of thermo-regulation--everyone stays just the right distance from the boiling hot water!*
*Ahhhh... Curtis Williams enjoys the soak at the end of a hard day...*
*Late in the day, the sun sparkles over the Hot Creek water*
*Mariel decides to take the icy swim down the river back to the entrance...*
*And a farewell wave to everyone back home!*
*And our new best friend is waiting for us back home at SNARL. Can you guess his name?*
*View a short video clip of Hot Creek fumaroles [1.36 MB]*	Click here