HR: 1340h
AN: GP13A-0017    [Abstracts]
TI: Effect of Multi-cycle Heat Treatment and Pre-history Dependence On Partial Thermoremanence (pTRM) and pTRM Tails
AU: * Yu, Y
EM: yjyu@ucsd.edu
AF: Scripps Institution of Oceanography, Geosciences Research Division, 9500 Gilman Drive, Dept 0220, La Jolla, CA 92122 United States
AU: Tauxe, L
EM: ltauxe@ucsd.edu
AF: Scripps Institution of Oceanography, Geosciences Research Division, 9500 Gilman Drive, Dept 0220, La Jolla, CA 92122 United States
AB: We test two fundamental assumptions embedded in Thellier experiments, the initial state dependence and the effect of multi-cycle heat treatment. We observe that the magnitude of partial thermoremanent magnetizations (pTRMs) imparted on an initial state of thermal demagnetization is larger than those of pTRMs in the presence of a TRM. A multi-cycle Thellier analysis on coarse-grained magnetites progressively produces more intense pTRMs and progressively erases more of the pTRM tails. Both pre-history and multi-cycle dependence will likely enhance the non-linear features of the Arai plot for coarse-grained magnetites.
DE: 1500 GEOMAGNETISM AND PALEOMAGNETISM
DE: 1519 Magnetic mineralogy and petrology
DE: 1521 Paleointensity
DE: 1540 Rock and mineral magnetism
DE: 1594 Instruments and techniques
SC: Geomagnetism and Paleomagnetism [GP]
MN: Fall Meeting 2005