When I was studying biology in high school, our teacher (frum) asked us
how can we possibly understand the scientific experiments about fossils
found to be "millions" or even "billions" of years old? Her answer was,
that according to some Rabbinic sources, the Mabul, Noach's flood, caused
heavy pressure on the universe and it could very well be that stones that
are only 5000 years old, appear to be much more ancient, because of the
utter havoc and upheaval that the flood caused to them. Food for thought!!