IGPP Seminar Series

Some new applications of isotopes produced on the Earth, and those accreted from space

by Dr. Devendra Lal
Scripps Institution of Oceanography, La Jolla

Abstract

The incorporation of a foreign substance in any matter often causes a remarkable change in the substance. If the introduction occurs at different epochs in the past, such events generally produce archival records. Science is replete with examples where one takes cognizance of these events to construct the evolutionary history of matter. With advances in the techniques of measurements, a miniscule change, previously considered immeasurable, has often become measurable, opening new windows in the field of paleontology. In this talk I would discuss examples of recently investigated applications of isotopes produced on the Earth, and those accreted from outer space, which reveal information on physical processes occurring in the interplanetary space, and on the Earth. Specific examples included in the talk are:
  1. Large century time-scale changes in solar activity in the past 32 Kyr
  2. Collisional and chemical fates of IDPs and meteoroids in the Earth's atmosphere.
  3. Recent applications of cosmogenic 'garden-variety' and 'in situ' produced isotopes in corals.
Tuesday, 04 October 2005
3853 Slichter Hall
Refreshments at 3:45 PM
Lecture at 4:00 PM