HR: 0800h
AN: B31D-0619    [Abstracts]
TI: Testing the Paleocene-Eocene Thermal Maximum Magnetofossil Spike Hypothesis
AU: * Tikoo, S M
EM: tikoo@its.caltech.edu
AF: California Institute of Technology, Division of Geological and Planetary Sciences, MC 170- 25, 1200 E. California Blvd., Pasadena, CA 91125, United States
AU: Kopp, R E
EM: rkopp@princeton.edu
AF: Princeton University, Department of Geosciences, Guyot Hall, Washington Road, Princeton, NJ 08544, United States
AU: Smirnov, A V
EM: asmirnov@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences, Houghton, MI 49931-1295, United States
AU: Raub, T D
EM: timraub@caltech.edu
AF: California Institute of Technology, Division of Geological and Planetary Sciences, MC 170- 25, 1200 E. California Blvd., Pasadena, CA 91125, United States
AU: Schumann, D
EM: schumann@eps.mcgill.ca
AF: McGill University, Department of Earth and Planetary Sciences, 3640 University Street, Montreal, QC H3A 2B2, Canada
AU: Vali, H
EM: vali@eps.mcgill.ca
AF: McGill University, Department of Earth and Planetary Sciences, 3640 University Street, Montreal, QC H3A 2B2, Canada
AU: Kirschvink, J L
EM: kirschvink@caltech.edu
AF: California Institute of Technology, Division of Geological and Planetary Sciences, MC 170- 25, 1200 E. California Blvd., Pasadena, CA 91125, United States
AB: Ferromagnetic resonance (FMR) spectroscopy detected a magnetofossil spike in Paleocene-Eocene Thermal Maximum (PETM) kaolinitic siltstone of New Jersey's Atlantic Coastal Plain, confirmed by two independent TEM studies and consistent with (but not required by) data from conventional rock magnetic analyses [1,2]. Applying first-order reversal curve (FORC) analysis to the same sediments demonstrates for the first time that ancient magnetofossils bear a FORC signature similar to that of both cultured and environmental magnetotactic bacteria. In order to test whether the observed PETM magnetofossil enrichment was a local or global phenomenon, we compare multi-proxy enviromagnetic profiles through the Atlantic Coastal Plain clay and present new FMR and rock-magnetic stratigraphies through other Paleocene-Eocene boundary sections. Our analyses of samples from the Paleocene-Eocene GSSP at Dababiya, Egypt, indicate the presence of a positive anisotropic, medium- to-high coercivity ferromagnetic component with FMR signatures similar to transitional signatures immediately preceding and following the magnetofossil spike in New Jersey. References: [1] R. E. Kopp,T. D. Raub, D. Schumann, H. Vali, A. V. Smirnov, and J. L. Kirschvink, 2007. Paleoceanography (in press). [2] P. C. Lippert and J. C. Zachos, 2007. Paleoceanography (in press).
DE: 0419 Biomineralization
DE: 0452 Instruments and techniques
DE: 1505 Biogenic magnetic minerals
DE: 1540 Rock and mineral magnetism
DE: 4948 Paleocene/Eocene thermal maximum
SC: Biogeosciences [B]
MN: 2007 Fall Meeting