HR: 08:15h
AN: GP41B-02    [Abstracts]
TI: A 300 kyr Record of Geomagnetic Excursions and Paleointensity From the Irminger Basin: Candidates for Mono Lake, Laschamp, Iceland Basin, Jamaica and Pringle Falls?
AU: * Channell, J E
EM: jetc@nersp.nerdc.ufl.edu
AF: University of Florida, Dept. Geological Sciences, PO Box 112120, Gainesville, FL 32611 United States
AB: Sediments recovered at ODP Site 919, off east Greenland, record geomagnetic directional excursions at 33 ka and 40 ka (Mono Lake and Laschamp), and at 187 ka (Iceland Basin), 208 ka (Jamaica?) and at 220 ka (Pringle Falls). U-channel records are augmented by 1-cm discrete samples collected back-to-back alongside the u-channel troughs. Deconvolution of the u-channel records yields records that can be closely matched to the discrete sample data. The age-model based on planktic oxygen isotope data (St. John et al., Marine Geology, in press) is consistent with the relative paleointensity record and the recognition of Ash Layer 2 (55 ka). The results indicate that the Mono Lake and Laschamp excursions, and the Iceland Basin and Pringle Falls (and perhaps also Jamaica), are distinct excursions, rarely recorded together in individual stratigraphic sections. Why are they recorded at ODP Site 919? Mean sedimentation rates are 22 cm/kyr in MIS 3 where Mono Lake/Laschamp are recorded, but sedimentation rates do not appear to be especially high in MIS 7 (13 cm/kyr) where candidates for Iceland Basin/Jamaica/Pringle Falls are recorded.
DE: 1513 Geomagnetic excursions
DE: 1520 Magnetostratigraphy
DE: 1521 Paleointensity
DE: 1522 Paleomagnetic secular variation
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2004 AGU Fall Meeting