HR: 10:20h
AN: GP42A-01 [Abstracts]
TI: The Matuyama-Brunhes Reversal: a Global and Temporal Perspective
AU: * Brown, M C
EM: m.c.brown@liv.ac.uk
AF: University of Liverpool, Geomagnetism Laboratory, Department of Earth and Ocean
Sciences, University of Liverpool, Liverpool, L69 7ZE, United Kingdom
AU: Gratton, M N
EM: gratton@liv.ac.uk
AF: University of Liverpool, Geomagnetism Laboratory, Department of Earth and Ocean
Sciences, University of Liverpool, Liverpool, L69 7ZE, United Kingdom
AU: Holme, R
EM: holme@liv.ac.uk
AF: University of Liverpool, Geomagnetism Laboratory, Department of Earth and Ocean
Sciences, University of Liverpool, Liverpool, L69 7ZE, United Kingdom
AU: Shaw, J
EM: shaw@liv.ac.uk
AF: University of Liverpool, Geomagnetism Laboratory, Department of Earth and Ocean
Sciences, University of Liverpool, Liverpool, L69 7ZE, United Kingdom
AB:
We present new palaeointensity and palaeodirectional results from the Matuyama-Brunhes geomagnetic field
reversal. Dated volcanic sequences from four global locations: La Palma, Chile, Iceland and Guadeloupe, are
investigated. These sections sample the Matuyama-Brunhes boundary, possible precursors, and fluctuations in
the magnetic field prior to the main polarity reversal. Absolute palaeointensity values were determined using the
14 GHz microwave systems at the Geomagnetism Laboratory, University of Liverpool. New directional results
(from thermal demagnetisation) and published directional data are combined with new microwave intensity data
to define the full vector of the field during the reversal. We compare our data with 1) other published data for the
Matuyama-Brunhes reversal and other reversal records that have both intensity and directional data; 2) a simple
mathematical reversal model based upon CALS7K.2 (Brown et al., Geophys. J. Int, 168, 541-551, 2007); 3) the
iterative Bayesian model of the Matuyama-Brunhes reversal, IMMAB4 (Leonhardt and Fabian, Earth Planet. Sci.
Lett., 253, 172-195, 2007).
DE: 1521 Paleointensity
DE: 1535 Reversals: process, timescale, magnetostratigraphy
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2007 Fall Meeting