Dissolution is our specialty...
I am a geologist with a particular interest in cosmic-ray-produced nuclides. With various students and collaborators, I am working on several projects in Antarctica, some aimed at dating the last glacial maximum, another dealing with the enigmatic ice in Beacon Valley. Other projects include the history of erosion beneath the Laurentide Ice Sheet, survival of ancient landscapes in Australian and South America, erosion and sediment transport in the Pacific northwest, and reconstruction of the last ice sheet in Britain. The
publications listed elsewhere on this website provide further details of my research.
I am also involved in the never-ending game of calibrating cosmogenic nuclide production rates, where my specialty is the production of Be-10, Al-26 and Cl-36, both at the surface and deep below ground.
I'm generally interested in Quaternary stratigraphy, geomorphology and
landscape evolution, and geochronology. I'm currently: 1) dating late
Pliocene-early Pleistocene glacial (and other) deposits via Be-10 and
Al-26 measurements; 2) studying erosion and sediment transport in the
Pacific Northwest and south Utah; 3) sorting out cosmogenic-nuclide
systematics, in particular low-energy neutron transport near snow-covered
surfaces; 4) studying landscape geomorphology with high-resolution digital
topography; 5) reconstructing Antarctic ice sheet retreat using glacial
geology and cosmogenic-nuclide measurements, and 6) applying
in a variety of other projects, mostly to do with geochronology.
I have broad interests in geomorphology and tectonics. At present I am working on measuring cosmogenic Be-10 in river sediments from the eastern Himalayan syntaxis to constrain spatial variability in erosion in the region. Additionally, I am working to develop a quantitative understanding of channel cross-sectional form in bedrock rivers in order to improve current models of bedrock river incision. I am also interested in developing better ways to use remote sensing and GIS to infer the spatial variability of erosion rates in active orogens.
Claire is planning a PhD in glacial geology, but first, she's been set the Herculean task of dating the last glacial maximum in the Ellsworth Mountains. Will she reduce the Al content of her quartz samples to less than 200 ppm and defeat the forces of evil?
Erosion rate measurements using cosmogenic nuclides. Spatial
variability in erosion rates. Landscape evolution modeling. Numerical
optimization. Starfish. Woohoo!
I'm currently involved with the Geodynamics of Indentor Corners Project
studying the eastern syntaxis of the Himalaya. I am now working to define
the timing and extent of Quaternary glaciations in southeast Tibet using exposure dating of glacially transported boulders. I will also be working with Noah Finnegan to measure erosion rates for
a range of watersheds in the area.
Former Geological Sciences student Joy Laydbak found that she liked chemistry, too, and returned to take charge of some of our chemistry operations. As she's here 9 to 5, we can now actually receive deliveries.
M.S., 2004; on leave 2004-5
Seth had the good fortune to work in Antarctica while doing his undergraduate degree at Colorado College. Unable to kick the habit, he's now using cosmogenic Be-10, Al-26 and Cl-36 in bedrock samples to unravel the long-term glacial history of Marie Byrd Land.
Cosmogenic Isotope Lab alumni --
Mineral separation expert; B.A., 2004
Previously in charge of sample prep operations; personally responsible for the first ever pure quartz extractions from carbonaceous graywackes of the California and Oregon coast ranges. See some results (large PDF poster) Oh yeah -- also a music major.
Aspiring volcanologist; some sort of degree, 2003
Jeff specialises in chlorine-36 dating, mostly of Hawaiian lavas. Jeff holds lab awards for consistently low Cl-36 blanks and best-dressed geochemist.
JPL veteran Derrick Johnson has implemented most of John's schemes
automation, including general equipment interfacing and software-writing tasks as well as electronics, plumbing, and LEGO robotics.
Meg Smith works in Antarctica, where she has been involved in a study of the world's oldest ice, in Beacon Valley. This picture shows much younger ice.