OSL dating, in the San Francisco volcanic field, uses quartz
xenocrysts and grains to measure the age of lava flows. Most often, OSL dating involves measuring the
time elapsed since a quartz grain in sediment was exposed to sunlight, which can
tell us, for example, when a river bed was overrun by a lava flow. We are having luck using quartz xenocrysts in
the basalt flows themselves (Rittenour et al., 2012), for the same purpose. The San Francisco volcanic field is rich in
quartz-bearing lava flows, allowing us to refine the dating method while
understanding more about the ages of volcanism.
Students in this project will spend the introductory two
weeks in Flagstaff and then travel to Utah State University to attend Tammy
Rittenour’s OSL short course, learning the ropes of sample collection,
separation, and analysis. Depending on
timing, students may return to Flagstaff for mapping and sample collection, or
samples may be in hand at the time of the short course. Either way, samples
collected will be analysed at USU, and the students will keep in “virtual”
touch with peers doing other students on their volcanoes.
At least one chemistry class is required for this project.
These projects are led by Nancy Riggs.