Download The Myth of Whole Mantle Convection – Judge for yourself

The Myth of Whole Mantle Convection
JUDGE FOR YOURSELF…
Don L. Anderson
http://www.mantleplumes.org/Penrose/BookChapterPD
Fs/RitsemaWebSuppl_Accepted.pdf

The large, red, 2000-km-wide
feature extends from the
southern hemisphere under the
Shona and Bouvet volcanic
regions to the Afar region, some
7000 km distant.

It has been assumed to be a
continuous hot feature that
penetrates the whole mantle.
References
Ritsema, J., Global seismic maps, Web supplement, 2005.
(http://www.mantleplumes.org/TopPages/TheP3Book.html)
Ritsema, J., van Heijst, H. J., and Woodhouse, J. H.,
Complex shearwave velocity structure imaged beneath
Africa and Iceland, Science, 286, 1925–1928, 1999.
Evidence for whole mantle convection
QuickTime™ and a
TIFF (Uncomp resse d) de com press or
are nee ded to s ee this picture.
Visual impression of a few
color-saturated
tomographic crosssections
Images that suggest whole mantle convection
Q uickTim e™ and a
TI FF ( LZW) decom pr essor
ar e needed t o see t his pict ur e.
QuickTime™ and a
TIFF (Uncomp resse d) de com press or
are nee ded to s ee this picture.
Images that suggest slab flattening
QuickTime™ and a
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are needed to see this picture.
VISUAL INTERPRETATIONS ARE NOT ALWAYS THE BEST,
BUT....
Upper mantle
Mesosphere
L
O
W
E
R
1000-km
Abyss
D’
M
A
N
T
L
E
D”
The transition zone is a crust-slab-water filter but it filters
from above, not below
“It is now well established that oceanic plates sink
into the lower mantle at subduction zones…”
Ritsema, 2005
Qu ickTim e™ a nd a
TIFF (Un comp resse d) de comp resso r
are need ed to see this picture.
Transition Zone thickness is independent
of hotspot and ‘megaplume’ locations
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
With this color scheme there are no
whole mantle slabs
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
Cartoons are used to interpret the
images as slabs and plumes
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TIFF (Uncompressed) decompressor
are needed to see this picture.
References

Fukao, Y., Widiyantoro, S., and
Obayashi, M., Stagnant slabs in the
upper and lower mantle transition
region, Rev. Geophy. 28,291–323,
2001.
Saturated images showing slab-like features
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Correlations between seismic velocities (solid) and
between velocities and densities (dots and dashes)
Different color schemes
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Deep or shallow Iceland?
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TIFF (Uncompressed) decompressor
are needed to see this picture.
Different views across Iceland
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.