During my teaching career, my research focused on the processes that shaped the evolution and architecture of continents, particularly the timescale over and/or the rate at which crustal processes operated in the past.  My work integrated field studies, geochemical and isotopic analysis, quantitative modelling, and U-Pb geochronology.

I investigated magmatism associated with the breakup of continents about 700 million years ago (in the Blue Ridge province, northern Virginia), volcanism associated with the formation of the Atlantic Ocean basin about 220 million years ago (in the Newark Basin, New Jersey), deformation, metamorphism and magmatism associated with the growth of North America between 1,800 and 1,600 million years ago (in the Grand Canyon, Arizona), and the nature of magmatic processes that operated in the plumbing systems beneath ancient, subduction-related volcanoes as preserved in granite-gabbro intrusions (on the coast of Maine and in the northern Sierra Nevada batholith, California).

More recently, my students and I employed multi-proxy-based strategies for identifying the source rocks of clastic sedimentary rocks on ancient continents.  Specifically, we utilized textural data, trace element compositional data, and U-Pb geochronologic dates of zircon crystals to directly compare detrital zircon grains in Permian sandstones of the Delaware Basin in west Texas to zircon crystals from possible source rocks that were exposed on the supercontinent Pangea about 240 million years ago. 

Since I retired in 2018, I have continued to work on the provenance of deltaic sandstones deposited on the supercontinent Pangea.  I also plan to continue research projects designed to constrain the age and duration of subvolcanic, bimodal magmatism that formed Silurian granite-gabbro intrusions on the coast of Maine, including the Cadillac Mountain intrusion exposed in and around Acadia National Park.