Effect of Shock on the Magnetic Properties of Pyrrhotite, the Martian Crust, and Meteorites
Access StatusFull text of the requested work is not available in DASH at this time ("dark deposit"). For more information on dark deposits, see our FAQ.
Louzada, Karin L.
Weiss, Benjamin P.
MetadataShow full item record
CitationLouzada, Karin L., Sarah T. Stewart, and Benjamin P. Weiss. 2007. Effect of shock on the magnetic properties of pyrrhotite, the Martian crust, and meteorites. Geophysical Research Letters 34, no. L05204: 1-5.
AbstractWe performed planar shock recovery experiments on natural pyrrhotite at pressures up to 6.9 GPa. We find that high-field isothermal remanent magnetization in pyrrhotite is demagnetized up to 90% by shock due to preferential removal of low coercivity components of magnetization. Contrary to static experiments, we do not observe complete demagnetization. Post shock permanent changes in magnetic properties include increasing saturation isothermal remanent magnetization, bulk coercivity and low-temperature memory, and changes in squareness of hysteresis. These changes are consistent with an increase in the volume fraction of single domain grains. The lack of magnetic anomalies over large Martian impact basins is not expected to be solely due to shock demagnetization of the crust. We find that pyrrhotite-bearing rocks and meteorites can retain records of Martian magnetic fields even if shocked to pressures approaching 7 GPa. However, some paleointensity techniques may underestimate this field.
Citable link to this pagehttp://nrs.harvard.edu/urn-3:HUL.InstRepos:3224714
- FAS Scholarly Articles