High pressure magnetic transition in pyrrhotite and impact demagnetization on Mars
Name:
Rochette_et_al-2003-Geophysica ...
Size:
180.2Kb
Format:
PDF
Description:
Final Published Version
Affiliation
Univ Arizona, Lunar and Planetary LabIssue Date
2003-07
Metadata
Show full item recordPublisher
AMER GEOPHYSICAL UNIONCitation
High pressure magnetic transition in pyrrhotite and impact demagnetization on Mars 2003, 30 (13) Geophysical Research LettersJournal
Geophysical Research LettersRights
Copyright 2003 by the American Geophysical Union.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
Using neutron diffraction under pressure at room temperature, we observed that pyrrhotite undergoes a ferrimagnetic to paramagnetic transition at about 2.8 GPa. Complete demagnetization of remanence at the same pressure is confirmed in an independent experiment. Such a process provides a quantitative explanation of the magnetic structure of the Martian Southern Hemisphere assuming that pyrrhotite is the major magnetic mineral and that our static experiments can be extrapolated to dynamic pressure conditions. Indeed, the 3 GPa isobaric line during the two large impacts of Argyre and Hellas separates the magnetized and unmagnetized zones. We also infer a reinterpretation of Martian meteorites paleomagnetic signal.Note
6 month embargo; First published: 5 July 2003ISSN
00948276Version
Final published versionSponsors
Project supported by the PNP program from CNES and CNRS.Additional Links
http://doi.wiley.com/10.1029/2003GL017359ae974a485f413a2113503eed53cd6c53
10.1029/2003GL017359