Polystrate fossil trees show tree trunks passing through many layers and
several meters of sediments. Obviously, the sediments must have been laid
down suddenly, not at the gradual rates proposed by uniformitarian
geology.
Sudden deposition is not a problem for uniformitarian geology. Single
floods can deposit sediments up to several feet thick. Furthermore,
trees buried in such sediments do not die and decay immediately; the
trunks can remain there for years or even decades.