Below are a wonderful paper and talk about determining whether
artefact scatters are "in situ" and what it means to be "in situ."

Ward, I., Ross, P. and Fandry, C., 2021. There can be no confidence
that the “first marine” and “in situ” artefact scatters in the Dampier
Archipelago, NW Australia are in their primary archaeological context.
[www.researchgate.net]
[osf.io]

More paper of Igrid Ward:
[www.researchgate.net]

Sedimentary processes and sedimentology help test whether
coastal archaeological artefact scatters are underwater and in
situ, NW Australia by Piers Larcombe & Ingrid Ward, University
of Western Australia, SedOne, March 2022
[www.youtube.com]
[sedsonline.com]

Yours,

Paul H.

"The past is never dead. It's not even past."
William Faulkner, Act 1, Scene III, Requiem for a Nun (1951)