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dc.contributor.authorHalekas, J. S.en
dc.date.accessioned2017-05-05T20:48:16Z
dc.date.available2017-05-05T20:48:16Z
dc.date.issued2002
dc.identifier.citationDemagnetization signatures of lunar impact craters 2002, 29 (13) Geophysical Research Lettersen
dc.identifier.issn0094-8276
dc.identifier.doi10.1029/2001GL013924
dc.identifier.urihttp://hdl.handle.net/10150/623415
dc.description.abstractWe investigate the crustal magnetic signatures of lunar craters using Lunar Prospector (LP) electron reflectometer data. Craters of all ages often have associated magnetic lows, showing that crustal fields were present even in pre-Nectarian times (≳3.9 Ga). Magnetic lows extend to ∼2–4 crater radii, suggesting shock rather than thermal demagnetization. Younger craters are more likely to have clear and complete demagnetization signatures, suggesting that many older magnetic lows have been subsequently obscured. No size dependence is found for craters larger than 50 km in diameter, suggesting that demagnetization effects for all craters in this size range completely penetrate the magnetized layer. If shock demagnetization is responsible, this suggests an upper limit of ∼50 km for the depth of magnetization. Evidence of edge effects due to magnetization contrasts may show that strong far-side crustal fields are coherent at scales of ∼25 km.
dc.description.sponsorshipResearch at the University of California, Berkeley, was supported by NASA through subcontract LRI-99-101 from the Lunar Research Institute.en
dc.language.isoenen
dc.publisherAMER GEOPHYSICAL UNIONen
dc.relation.urlhttp://doi.wiley.com/10.1029/2001GL013924en
dc.rightsCopyright 2002 by the American Geophysical Union.en
dc.titleDemagnetization signatures of lunar impact cratersen
dc.typeArticleen
dc.contributor.departmentUniv Arizona, Lunar & Planetary Laben
dc.identifier.journalGeophysical Research Lettersen
dc.description.note6 month embargo; First published:12 July 2002en
dc.description.collectioninformationThis 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.en
dc.eprint.versionFinal published versionen
refterms.dateFOA2003-01-13T00:00:00Z
html.description.abstractWe investigate the crustal magnetic signatures of lunar craters using Lunar Prospector (LP) electron reflectometer data. Craters of all ages often have associated magnetic lows, showing that crustal fields were present even in pre-Nectarian times (≳3.9 Ga). Magnetic lows extend to ∼2–4 crater radii, suggesting shock rather than thermal demagnetization. Younger craters are more likely to have clear and complete demagnetization signatures, suggesting that many older magnetic lows have been subsequently obscured. No size dependence is found for craters larger than 50 km in diameter, suggesting that demagnetization effects for all craters in this size range completely penetrate the magnetized layer. If shock demagnetization is responsible, this suggests an upper limit of ∼50 km for the depth of magnetization. Evidence of edge effects due to magnetization contrasts may show that strong far-side crustal fields are coherent at scales of ∼25 km.


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