Hi, David. Yes, some bivalves can burrow upward through the sediment that
has been dumped on top of them. Others can't. The amount differs from
species to species, and, I suspect, is also dependent on how exhausted the
poor dears are before they start. There is actually a fairly large
literature on the subject, and I'd guess that 0.5 m (half a yard) of
sediment would be enough to wipe out most of the fauna. But "book
knowledge" is nothing like actually being there on the spot before and
after a beach replenishment, and I do not have that experience.
 
Apologies to FRED Hinkle for calling him FRANK... We have a Frank Hinkle
here on staff, no kidding!
 
Andrew K. Rindsberg
Geological Survey of Alabama