Research Projects

My research and that of my students, postdocs, and collaborators, covers a wide range, including experimental development of (U-Th)/He thermo- and geochronology, applications of thermochronology in tectonic geomorphology, and igneous geochemistry. Lab manager Stefan Nicolescu and I have set up several laser (Nd:YAG and CO2) extraction, processing, and measurement lines for 4He that I moved here to the UofA. These instruments will complement extant sector gas-source mass specs (MAP 215-50 and VG5400) that perform a variety of other noble gas measurements including 40Ar/39Ar dating. We also have a state-of-the-art microscopy lab for sample preparation, and a ThermoFisher Element2 high-resolution ICP-MS for measuring U-Th-Sm in He dating, as well as a wide range of other trace metals in many different types of samples.

Below are some of my ongoing projects.


Tectonic Geomorphology of the Washington Cascades

Below: Apatite (U-Th)/He cooling ages overlain on bedrock geology, faults and seismicity, slope, and precipitation maps, in the central Washington Cascades. These data include some from a collaborative project from several years ago with Todd Ehlers, Sara Gran Mitchell, and Dave Montgomery, and also some from Peter Isaacson's 2005 Yale Senior Thesis.


Glacial erosion and climate-erosion-tectonic coupling in the Patagonian Andes
a collaborative project with Mark Brandon, Jon Tomkin, Stuart Thomson, and Christien Vasquez

After Porter (1981), as shown in Broeker and Denton (1990).


Wildfire in geomorphology and paleowildfire in the geologic record
a collaborative project with Stuart Thomson, Devin McPhillips, Ray Donelick, and Josh Roering


Combined (U-Th)/He and U/Pb dating of single detrital zircon grains
a collaborative project with Charlotte Allen and Ian Campbell, at the ANU.

Right: He-Pb double-dates of detrital zircons from modern (and a couple of Eocene) North American Rivers.



Geochronology of clinker and geomorphic evolution of the Powder River Basin, Wyoming
a collaborative project with Ed Heffern and Catherine Riihimaki.