Our faculty research comprises field and laboratory based investigations into the tectonics of the continental crust and deeper mantle in both active and ancient settings at timescales ranging from a single earthquake event to billions of years. We combine a variety of techniques to address questions ranging from regional tectonic histories, the structural evolution of brittle and ductile fault systems, the mechanical behavior of rocks at high pressure and temperature, the absolute dating of deformation events, and the thermal evolution of mountain belts.
Pamela C. Burnley: Associate Research Professor
High Pressure Rock Deformation, Mineral Physics, Metamorphic Petrology, Geoscience Education
Andrew D. Hanson: Associate Professor
Sedimentology, Basin Analysis, Petroleum Geology, and Organic Geochemistry
Rodney V. Metcalf: Associate Professor
Metamorphic and Igneous Petrology, Geochemistry
Terry L. Spell: Associate Professor
Wanda J. Taylor: Professor
Structural Geology, Extensional and Contractional Tectonics
Michael L. Wells: Professor
Tectonics, Structural Geology, Microstructural Analysis, Thermochronology
Individual faculty have past, ongoing, and future field-based investigations into the tectonic history and evolution of such places as: the Cordilleran Orogen of the western United States, the Klamath Mountains province of California and Oregon, the Franciscan subduction complex of California, the Basin and Range extensional province of the western United States, the Sierras Pampeanas of northwest Argentina, and the median batholith of South Island New Zealand. Aside from location-specific tectonic histories, some of the large scale tectonic processes studied include synconvergent extension, coupling-decoupling in continental lithosphere through evaluation of coeval upper and lower crustal deformation, melt-enhanced deformation and melt segregation, exhumation of high and ultra-high pressure rocks, and mechanisms of continental growth.
Our faculty apply a diverse range of field and laboratory based techniques to study the kinematic evolution of brittle and ductile fault zones in both extensional and contractional settings and the rheologic and mechanical behavior of Earth’s materials. Specific research topics include strain and reaction softening mechanisms and their role in deformation partitioning and reactivation; applications of incremental and finite strain analysis to tectonic problems; deformation mechanisms and resulting lattice-preferred orientation, and deformation microstructures and their paleotemperature and rheological significance.
Our faculty also use experimental studies to understand ductile deformation of rocks within the earth’s interior. In addition to laboratory studies conducted at UNLV, studies utilizing in-situ synchrotron x-ray diffraction are revealing the processes by which the crystals within a rock deform and interact to produce the overall mechanical response of the rock. The in-situ experiments are combined with detailed microstructural analysis of specimens which will facilitate comparison with natural specimens. Specific topics currently under investigation include the deformation of quartz and olivine at high pressure and temperature.
Our faculty combines multiple methods of absolute and relative dating to determine the progressive deformation histories and thermal evolution of rocks within contractional and extensional tectonic settings. Much of the thermal history in orogenic belts can be unraveled using the 40Ar/39Ar technique and are performed in the Nevada Isotope Geochronology Laboratory (NIGL) here in the Department of Geosciences at UNLV, both using furnace step heating of mineral separates including multi-diffusion domain analysis of K-feldspar, and in situanalysis of minerals in their textural growth positions by UV laser probe. Our faculty and students also collaborate (commonly including extended visitations) with a number of other laboratories for techniques such as U-Th-Pb dating of zircon, monazite and sphene, Lu-Hf garnet geochronology, (U-Th)/He analysis, and fission track thermochronometry. Applications include determining slip rates on detachment faults, dating growth of metamorphic porphyroblasts to add time to metamorphic P-T paths, dating mineral fibers in strain fringes to date deformation and determine strain rates, and evaluating cooling age and history discordances across faults to distinguish thrust and normal faults and evaluate slip magnitudes.