The dynamical origin of Hawaiian volcanism

Computer Science

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

78

Scientific paper

We study the dynamics of melting in the Hawaiian plume using a 3D variable-viscosity convection model outfitted with a melting parameterization that permits calculation of the local melting rate and the distribution of buoyant depleted residual material. From a suite of 45 steady-state numerical experiments, we derive complete scaling laws for the total rate of melting /M and the height /H and width /W of the topographic swell as functions of the lithospheric thickness zl and the plume's maximum potential temperature θi, thermal buoyancy flux /B, and minimum viscosity ηp. Assuming 1500°C<θi<1600°C, the observed values of /M, /H and /W can only be matched if zl<=89 km, 2200 kg s-1 /<=B<=3500 kg s-1, and ηp>=5×1017 Pas. We study a reference Hawaiian model satisfying these constraints. The depletion anomaly is narrower than the thermal anomaly, and carries 24% of the total (thermal plus depletion) buoyancy flux. Its buoyancy contributes 350 m of the uplift along the swell axis, and reduces the geoid/topography ratio by 16% relative to a model without depletion buoyancy. All the material that melts comes from the hottest central part of the plume, and no direct melting of the asthenosphere or lithosphere occurs. Melting occurs both in a primary melting zone above the plume stem and in a weaker secondary melting zone 300-500 km downstream, separated by an interval where no melting occurs. We propose that the preshield-, shield-, and postshield stages of Hawaiian volcanism are generated by the primary melting zone, and the rejuvenated stage by the secondary melting zone.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The dynamical origin of Hawaiian volcanism 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 The dynamical origin of Hawaiian volcanism, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The dynamical origin of Hawaiian volcanism will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1558199

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.