Information accumulated in these studies has led to explorations of increasingly greater scope, including patterns of phytogeography, plant-animal interactions and broad scale evolution. Isotope Geology, Geochronology, Use of Strontium and Lead Isotopes as Natural Tracers, Meteorite and Lunar Studies. Use of radiogenic isotopes and trace elements as tracers to study the age and petrogenesis of lavas and magmas, with applications to the geochemical evolution of the earth's crust and mantle. Present work in two volcanic areas, San Francisco Volcanic Field in north central Arizona and north Lake Tahoe-Truckee area, California. Vertebrate Paleontology, Mammalian Systematics Phylogenetic analysis and the application of mammalian paleontology to geological problems.
Geologic interests center on several questions in the Andean Main Range of central Chile.
I am a structural geologist working primarily in metamorphic rocks. I am especially interested in the interplay between evolutionary, ecological, behavioral, and genetic factors, and how they affect geographic variation and the process of natural selection in natural populations. My approach is a mixture of theory, field observations, and experimental manipulation, in both field and laboratory. The processes and grain-size characteristics of sediment transport, deposition, and deformation systems. We study microalgal-invertebrate symbiosis, in particular those symbioses living on coral reefs.