Ok well heres a weak justification to show how geology 1337 i am.
Haha well i live right next to a former volcano (Mt. Warning) which blew up 200 million years ago. Behind the volcano approximately 100km's inland are the foothills of the Great dividing range which were uplifted more than 50 million years ago. Now the problem with all of this is that when the volcano blew its top, it sent bassalt everywhere which over time weathers into Argillite and a sandy clay which, when wet under extreme pressure (such as a heap of water) would be disturbed removing the layers creating a layer of mixed soil which would look like fill. However, to find fill in these regions would be close to impossible given that it needs to be moved there and no one lives there or goes out that way.
This is not to say that signs of flooding aren;t there. Marine clay contains sandstones and often a fine to medium grained sand which indicates a large volume flood a long time ago. However, foreign soil types are usually restricted to little speckles and less than 10% foreign matter.
In the case of a global flood, the permeability of soil over a very long time would create a suspension at the soil-air interface and completely disturb the top 400mm of soil making it look exactly like fill material and leave signs down to probably 1m (or the residual material which in Oz is often a clay with very very low permeability). Now, on top of that we would have new sediment which would be uniform.
The problem with this is that nowhere would we find more than 20mm-100mm of disturbed material underlying sediment because lets face it, it takes an enormous flood to disturb that much soil.
However, dig deeper (down to the residual soil usually 3-4m) and you will find shell matter as where i live used to be part of the continental shelf millions of years ago.
Soil doesn't lie as well as the bible does