Other
Scientific paper
May 2007
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007agusm.p23a..06f&link_type=abstract
American Geophysical Union, Spring Meeting 2007, abstract #P23A-06
Other
5734 Magnetic Fields And Magnetism, 6022 Impact Phenomena (5420, 8136), 6030 Magnetic Fields And Magnetism, 6250 Moon (1221)
Scientific paper
Models of lunar magnetism need to explain: (1) strong Natural Remanent Magnetization (NRM), indicated by IRMs normalization, in some of the returned Apollo Mare Basalts and Melt Rocks with ages from about 3.85Ae to 3.65 Ae, (2) magnetic anomalies antipodal to the young basins of a similar age, (3) the absence of major magnetic anomalies over these same basins and the presence of minor anomalies over uplifted basement. (4) strong fields with scale lengths of homogeneity of the order of kms, or less, are found over the Cayley Formations and similar material. Observation (1) has frequently been taken to require the presence of a lunar dynamo. However, this presents a dilemma. If there were a lunar dynamo at that time, why were the basin melt sheets not magnetized in the field of the dynamo. It is also an uncomfortable coincidence that the dynamo is only extant close to the time of heavy bombardment. Given these difficulties and questions of the efficiency of dynamo action in a lunar core, it is worth reexamining other possible explanations of lunar magnetism. Hood's model accounts for the antipodal anomalies, while the observations at Vredefort (Carpozen, et al., 2003) may account for the anomalies over central peaks and uplifted ring structures in major basins. Experimental work by Crawford and Schultz (1999) has demonstrated that impacts of projectiles traveling at kms/sec generate magnetic fields. Srnka et al, (1979) showed that magnetic fields can be recorded by shock with demagnetization characteristics similar to thermal remanent magnetization. The question that remains is whether all of the observed lunar magnetization can be explained directly by impact related magnetization, or indirectly through magnetization acquired in the remanent fields of material magnetized by impacts.
Adachi Tadashi
Fuller Michael M.
Halekas J.
Kletetschka Gunther
Kohout Tomas
No associations
LandOfFree
Lunar Magnetism: IRMs Normalization and Impact Related Magnetization. does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Lunar Magnetism: IRMs Normalization and Impact Related Magnetization., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lunar Magnetism: IRMs Normalization and Impact Related Magnetization. will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1035244