Just because you can't see them, doesn't mean the strata aren't there.
 
Dan Mouer and Carl Steen have described precisely what we found at the
aeolian Blueberry Hill site in Delaware (published in the DelDOT series).
We dug the site, basically a sand dune, by natural geological layers, which
were subdivided into arbitrary half-meter-square lifts five centimeters
deep.
 
Subdivisions of the larger "geological" layers were obscure at best. In
fact, we used a series of successive B horizons, identified by John Foss,
that were our basic vertical control.
 
When we analysed the contents of our 4500 cells, we discovered the
"turbation" Dan describes had caused artifact clusters (features?) within
the thicker aeolian deposits to spread vertically and horizontally until
they were shaped like the saucer section of a starship. Some had spread
more than others.
 
As we went downward, we identified ancient stabilized ground surfaces, with
gullies and pits, from times when the site had been relatively stable.
These were excavated and interpreted conventionally as natural layers.
 
But in the big dune deposits above and below these old ground surfaces, we
definitley were able to reconstruct loci that could be identified as old
living floors for which there were no apparent strata. To these deposits we
could apply the good old law of superposition.
 
There has been some work done in the Mediterranean, on sites that have been
cultivated for very long times, in which the upward and downward movement
of artifacts has been demonstrated. In these cases, layering is more of a
statistical exercise, because artifacts from all periods may be found in
all levels, but with a preponderance of old ones at the bottom and a
preponderance of new ones at the top. There was a write-up in Scientific
American a few years ago, I believe.
 
 
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|"Baby"  \
|1969 Land\_===__    See Baby performing at Assateague during
|IIA__Rover   ___|o  the R.O.V.E.R.S. RTV driving test event!
|_/ . \______/ . ||  http://www.aircast.com/peterg/assat7.JPG
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Ned Heite, Camden, DE  http://home.dmv.com/~eheite/index.html