HR: 12:05h
AN: V32B-08 INVITED    [Abstracts]
TI: Advances in Isotope Cosmochemistry and High-Resolution Chronology Using Extinct Radionuclides
AU: * Wadhwa, M
EM: wadhwa@asu.edu
AF: Center for Meteorite Studies, School of Earth and Space Exploration, Arizona State University, Box 871404, Tempe, AZ 85287-1404,
AB: Recent advances in analytical techniques for high precision isotopic measurements (particularly with the newest generation multicollector ICPMS, TIMS and SIMS instruments) have resulted in significant improvements in the ability to resolve small relative time differences (ΔT <<1 My) between events occurring in the earliest history of the Solar System. This presentation will provide an overview, with some specific examples, of recent applications of high-resolution chronometers based on several different extinct radionuclides to meteorites and their components. Some particular issues that will be addressed include: (1) concordance, or lack thereof, between various high-resolution relative chronometers based on the extinct radionuclides and the absolute Pb- Pb chronometer, (2) presence of isotopic heterogeneities in meteoritic materials and their implications for the application of these chronometers, and (3) estimates of the abundances and distributions of short-lived radionuclides in the early Solar System and implications for the environment of formation of the Solar protoplanetary disk.
DE: 1028 Composition of meteorites (3662, 6240)
DE: 1115 Radioisotope geochronology
DE: 1155 Extinct radionuclide geochronology
DE: 1160 Planetary and lunar geochronology
DE: 6240 Meteorites and tektites (1028, 3662)
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting