The University of Southampton
University of Southampton Institutional Repository

Repeating waveform initiated by a 180–190 ka geomagnetic excursion in western North America: Implications for field behavior during polarity transitions and subsequent secular variation.

Negrini, Robert M., Erbes, Daniel. B., Roberts, Andrew P., Verosub, Kenneth L., Sarna-Wojcicki, Andrei M. and Meyer, Charles E. (1994) Repeating waveform initiated by a 180–190 ka geomagnetic excursion in western North America: Implications for field behavior during polarity transitions and subsequent secular variation. Journal of Geophysical Research, 99, (B12), 24105 -24119.

Record type: Article

Abstract

New paleomagnetic, lithologic, and stratigraphic data are presented from the sediments of Lake Chewaucan in the Summer Lake Basin, Oregon. The new data place better age constraints on the sediments and improve the accuracy of the previously published paleomagnetic record from this locality. A complex, yet distinct, waveform is observed in all three components of the paleomagnetic vector. The waveform begins as the 180–190 ka Pringle Falls/Long Valley/Summer Lake II geomagnetic excursion and continues for two cycles after the excursion, until the record is interrupted by an unconformity that we correlate to the oxygen isotope stage 6/5e boundary. The waveform's directional morphology in virtual geomagnetic pole (VGP) space is defined by two clockwise loops followed by a distinctive counterclockwise, clockwise, counterclockwise looping sequence. The VGP paths of the two cycles after the excursion are rotated 180° about Earth's spin axis with respect to the VGP paths of the excursion cycle. The waveform also consists of a relative paleointensity variation which repeats during the two cycles after the excursion. The average paleointensity of the postexcursion waveform repetitions is high relative to the extremely low values that occur during the excursion. This observation indicates that excursion-initiated secular variations can occur after the field fully recovers from the low intensities which commonly typify excursions. Because of the similarities noted previously between this excursion and full polarity transitions (Trie et al., 1991), our new observations constrain models for a wide range of field behavior including polarity transitions, excursions, and secular variation.

Full text not available from this repository.

More information

Published date: 10 December 1994

Identifiers

Local EPrints ID: 66144
URI: http://eprints.soton.ac.uk/id/eprint/66144
ISSN: 0148-0227
PURE UUID: 5eb2545b-e74c-4d18-9074-be6ed8299ffd

Catalogue record

Date deposited: 05 May 2009
Last modified: 19 Jul 2017 00:27

Export record

Contributors

Author: Robert M. Negrini
Author: Daniel. B. Erbes
Author: Andrew P. Roberts
Author: Kenneth L. Verosub
Author: Andrei M. Sarna-Wojcicki
Author: Charles E. Meyer

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×