Request Expert

Expert has over two decades of expertise in radiogenic isotope geochemistry, especially as it relates to geochronology for study of crustal evolution and petrogenesis mostly via U-Th-Pb zircon and other isotopic techniques (Lu-Hf, Sm-Nd). He is experienced in the documentation of field relationships in complex terranes by high-resolution mapping at the appropriate scale (1:5-1:1000) to guide detailed geochemical sampling. Expert creates novel applications in secondary ion mass spectrometry (multi-collector ion microprobe; SIMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) for combined U-Pb zircon, Lu-Hf, 147,146Sm-143,142Nd and W isotope studies of the oldest rocks. He also investigates lunar rocks and martian and asteroidal meteorites, has formulated geochemically and cosmochemically constrained models for the thermal structure of planetary objects including Earth, Moon, asteroids, Kuiper Belt/Trans-Neptunian Objects and theoretical Exoplanets. Furthermore, he models pre- and post- closure temperature thermal chemical diffusion modeling of zircon and apatite. Finally, Expert has studied the evolution of atmospheric oxygen as it relates to evolution of biogeochemical cycles tracked by multiple S isotopes and trace metals (Ni, Co).