[meteorite-list] Another Reason That Meteorites Disappear

[Paul]

Dear Friends,

I hear a lot references made to meteorites disappearing 
after they fall to Earth because thy are destroyed by 
weathering. Bioturbation is another process that causes 
them to disappear relatively rapidly, within years from 
the ground surface is bioturbation. The churning of the 
upper horizons by animals and plants will caused large
objects, whether they be prehistoric and historic artifacts, 
meteorites, modern bricks and concrete pieces, and so 
forth, to gradually “sink” into the ground. Objects will 
sink to the depth at which the churning of the ground 
by bioturbation ceases to modify the soil. This forms a 
buried layer of stones and other objects called a 
“carpedolith” or “stone-layer”. When a carpedolith is 
exposed in a two dimensional outcrop, as in the sides 
of an artificial excavation, stream cutbank, or roadcut, 
it is called a “stone line”.

In areas where plant and animals rapidly churn the soil
to significant depth, meteorites will diappear from the
ground surface long before they are destroyed by 
terrestrial weathering processes. Depending on how 
intense the bioturbation is and the size of the meteorite, 
this can happen in a matter of decades, even years.

Some references are:

Johnson, D. L..  J. E. J. Domier, and D. N. Johnson, 
2005, Reflections on the Nature of Soil and Its 
Biomantle. Annals of the Association of American 
Geographers. vol. 95, no. 1, pp. 11–31

http://www.d.umn.edu/~pfarrell/Soils/SCIENCE%20articles/Soil%20as%20Biomantle.pdf

http://ltse.env.duke.edu/files/ltse/publications/Johnson_DL2005%20reflections%20on%20soil.pdf

Meysman, F. J. R., J. J. Middelburg and C. H.R. Heip, 
2006, Bioturbation: a fresh look at Darwin's last idea. 
Trends in Ecology and Evolution. vol. 21, no. 12, 
pp. 688-695.

http://194.171.24.200/ppages/jmiddelburg/downloads/1/Meysman_tree.pdf

Frolking, T. A. and B. T. Lepper, Geomorphic and 
Pedogenic Evidence for Bioturbation of Artifacts at a
Multicomponent Site in Licking County, Ohio, U.S.A.
Geoarchaeology. vol. 16, no. 3, pp. 243–262.

http://www.denison.edu/academics/departments/geosciences/munsonsprng_geoarch_2001.pdf

Johnson, D. L.,  C.L. Balek, and R.J. Schaetzl, 2005, 
Stonelayers (stone-lines) in Soils: A priori assumed 
to be basal parts of biomantles. Geological Society 
of America Abstracts with Programs vol. 37, No. 5, p. 77

http://gsa.confex.com/gsa/responses/2005NC/121.ppt

Animation on Dynamic Denudation/Biomantle Evolution

https://netfiles.uiuc.edu/jdomier/www/temp/biomantle.swf

Yours,

Paul H.