Current & Recent Research Projects

Mesoproterozoic Tectonic Evolution of the Southern Margin of Laurentia

A Grenville-aged orogenic belt formed on the southern margin of Laurentia south of the Llano front during the amalgamation of Rodinia. Plate boundary (dashed) in Llano uplift represents a collisional suture whereas that in west Texas represents closure of a small ocean basin. See Mosher (1998). Direction of tectonic transport (arrows) shown for Llano uplift and west Texas exposures. Inset shows location of Laurentian Grenville orogenic belts.We are developing and testing a new model for the ~ 1.1 Ga collisional orogen along the southern margin of Laurentia with specific emphasis on the Llano uplift of central Texas that exposes the core of the orogen and the Sierra Diablo foothills of west Texas where the metamorphic… read more

Evolution of the Pacific-Australian plate boundary, the Macquarie Ridge Complex, south of New Zealand

Since 40 Ma, this plate boundary has evolved from a paleo-spreading ridge to the present day transpressional transform boundary and locally is undergoing incipient subduction. We are investigating how strain was partitioned during the evolution of this boundary and the processes that accommodated this deformation… read more

Strain partitioning in shear zones

We are investigating the partitioning of constrictional and/or flattening strain during formation of ductile non-coaxial shear zones in extensional and contractional environments, including the formation of corrugations in metamorphic core complexes and… read more