My research and teaching focus on the tectonic evolution of continents and mountain belts. I use thermochronology, structural geology and isotope geochemistry to understand the evolution and deformation of the continental crust.

I have active research projects in western North America, Australia, Africa, and New Zealand. There are opportunities for graduate & undergraduate student research on many of these projects. Visit the research page of my web site for an overview of projects.

Current Research:

Supercontinent Cycles and Assembly of Gondwana
Supercontinent cycles remain one of the most significant and poorly understood aspects of the global geodynamic system. The Damara Orogen in Namibia records the assembly and break-up of two supercontents.

Transpressional Orogens and Oblique Plate Convergence
Many modern orogenic systems are dominated by oblique convergence and large strike-slip fault zones. The Kaoko Belt of the Damara Orogen exposes the deep crust of an ancient transpressional orogen.

Tectonic Setting and Kinematics of Eocene Extension in the Northern Rockies
We study metamorphic core complexes in Montana and Idaho to understand the Eocene plate tectonic setting, processes involved in exhumation and collapse of the Cordilleran Orogen, and the causes of the widespread Challis-Bitterroot igneous activity.

Basement Tectonics of Western North America
Understanding the evolution of Precambrian basement helps reveal the relationships between ancient and modern tectonic and magmatic processes.

Continental Growth in Accretionary Orogens
The Lachan Orogen of Australia preserves an excellent example of how continental crust forms from closing an oceanic back-arc basin.

Plutonic Imaging: Evidence for Two Proterozoic Mafic Underplating Events in the NW Wyoming Province from Hf-Isotopes of Zircon from Cretaceous Granitoids

Plutonic imaging provides a critical complement to geophysical studies that cannot provide estimates of crustal age diversity and true composition.