>
>Such cracks can and are known to have been produced subaqueously by
>histeresis shrinkage of chemically shortened clays. This is not to say
>that all mud cracks formed that way, just to sound a cautionary note to any
>dogmatic assertion.
Art,
You left out the fact that there are morphological differences between
SYNAERISIS (not histeresis which is a magnetic phenomenon I believe) cracks
and dessication cracks.
"Such subaqueous shrinkage cracks differ from subaerial
desiccation cracks in that they are not so well developed, the
cracks are rather narrow, and they do not possess well developed
V-shapes in transverse sections. In general, subaqueous
shrinkage cracks are less regular in form and often incomplete."
~ p 60 H. E. Reineck J. B. Singh Depositional Sedimentary
Environments New York: Springer-Verlag 1980
**
Desiccation mudcracks are generally continuous, polygonal, and
often of several generations with v- or u-shaped cross-sections
that are infilled from above. Synaeresis cracks, on the other
hand, are generally discontinuous, spindle, or sinuous in shape
and of one generation only, with v-or u-shaped cross-sections
that are infilled from either above or below." ~ p 1153
"Shrinkage Cracks: Desiccation or Synaeresis? P. S. Plummer and
V. A. Gostin Journal of Sedimentary Petrology Vol 51 #4 Dec 1981
We can tell the difference between the two.
glenn
Adam, Apes, and Anthropology: Finding the Soul of Fossil Man
and
Foundation, Fall and Flood
http://www.isource.net/~grmorton/dmd.htm