Sulfur's impact on core evolution and magnetic field generation on Ganymede

Details Sulfur's impact on core evolution and magnetic field generation on Ganymede Sulfur's impact on core evolution and magnetic field generation on Ganymede

Dec 2005

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005agufmgp43a0889h&link_type=abstract

American Geophysical Union, Fall Meeting 2005, abstract #GP43A-0889

Physics

5734 Magnetic Fields And Magnetism, 6222 Ganymede, 8147 Planetary Interiors (5430, 5724, 6024)

Scientific paper

Analysis of the melting relationships of potential core forming materials in Ganymede indicate that convective motions capable of generating the satellite's magnetic field may be driven, in-part, either by iron "snow" forming below the core-mantle boundary or solid iron sulfide floating upward from the deep core. Eutectic melting temperatures in the binary Fe-FeS system decrease with increasing pressure over the interval of core pressures on Ganymede (<14 GPa). Comparison of melting temperatures to adiabatic temperature gradients in the core suggest that solid iron is thermodynamically stable at shallow levels for bulk core compositions more iron-rich than eutectic (i.e., <21 wt % S). Calculations based on high-pressure solid-liquid phase relationships in the Fe-FeS system indicate that Fe snow or floatation of solid FeS, depending on whether the core composition is more or less Fe-rich than eutectic, is an inevitable consequence of cooling Ganymede's core. Our results demonstrate that these conclusions are robust over a wide-range of plausible three-layer internal structures and thermal evolution scenarios. Using scaling arguments based on recent experimental work we estimate core Rossby and magnetic Reynolds numbers plausibly consistent with a dynamo being generated in Ganymede's core via Fe-snow. Depending on core composition, either shallow formation of Fe snow or deep precipitation and subsequent floatation of FeS is an important mechanism for driving the moon's strong internally-generated magnetic field.

Affiliated with

Also associated with

No associations

Rating

Sulfur's impact on core evolution and magnetic field generation on Ganymede 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 Sulfur's impact on core evolution and magnetic field generation on Ganymede, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sulfur's impact on core evolution and magnetic field generation on Ganymede will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-752015