"Raindrop imprints can also tell us the location of the pre-Flood/ Flood boundary.
They have been reported in the Precambrian from the Uinta Mountains, India, Norway, and South Africa.
Some of these locations have multiple stratigraphic levels of raindrop imprints.
The raindrop imprints can be explained the same way as dinosaur tracks, eggs, and scavenged bonebeds can be explained, early in the Flood.
This is by the BEDS (Briefly Exposed Diluvial Sediments) hypothesis in which rapid sedimentation followed by a drop in local sea level can expose flat bedding planes for brief periods. Precambrian sedimentary rocks are normally thousands of meters thick, so it makes sense that they can be briefly exposed after heavy deposition. Raindrop imprints have to be rapidly buried in order to be preserved, which would have happened during the corresponding rise in local sea level. Multiple levels can be explained by this mechanism repeating several times."
CMI
And the rain was upon the earth
forty days and forty nights.
Genesis 7:12