HR: 0830h
AN: GP11C-0271    [PDF]
TI: Paleomagnetic Records of Corals From the Solomon Islands
AU: Rastegar, A
EM: arastegar@stanford.edu
AF: HIGP-SOEST, U. Hawaii, 1618 East-West Rd, Honolulu, HI 96822 United States
AU: * Fuller, M
EM: mfuller@soest.hawaii.edu
AF: HIGP-SOEST, U. Hawaii, 1618 East-West Rd, Honolulu, HI 96822 United States
AU: Taylor, F
EM: fred@utig.ig.utexas.edu
AF: School of Geosciences, U. Texas at Austin, 4412 Spicewood Springs Rd.,, Austin, TX 78759 United States
AB: The paleomagnetism of corals is potentially important because corals may afford high-resolution records of the geomagnetic field. Given the known ages of available corals, it may be possible to get such records for various times in the past few tens of thousands of years. To this end we have investigated the rock magnetism and possible paleomagnetic records of corals from the Solomon Islands. The magnetism of the corals studied is of order 10-7 to10-8 Am2/kg. However samples with masses of about 10 gms can be reliably measured with modern magnetometers. The Natural Remanent Magnetization (NRM) is of variable quality yielding some PCA MAD angles between 1 and 5 and inclinations consistent with the site at which the were drilled. Others are much less precise determinations and in erratic directions. We compared the AF demagnetization characteristics of the NRM with those of Anhysteretic Remanent Magnetization (ARM) and Isothermal Remanent Magnetization (IRM). This revealed that the better determinations are from samples in which the demagnetization behavior of NRM is very similar to that of ARM and in a ratio of approximately a few parts in a thousand to IRM.
DE: 1505 Biomagnetism
DE: 1512 Environmental magnetism
DE: 1522 Paleomagnetic secular variation
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2003 Fall Meeting