"Capt. Mooron" wrote in
:

Correct.... but "fluvial" would designate placer deposit via the
glacial stream... 'Alluvial" would describe it's flow pattern and
indicate the deposit grading.... generally sub-rounded to rounded
clast aggregates of sandy gravels dispersing coarse to fine with the
flow. "Strata" would be the correct description of the deposit body or
formation, while "stratum" would indicate the specific band or layer.

In either case an "alluvial rock" is incorrect terminology.

I love this stuff.... ;-)

Of course you do.

Bertie