Prior to what? If you can't use the dating to know the age of the layers how do you know when they were laid down? Do you see the circular logic in radiometric dating yet?
WHAT PASSED FOR SCIENCE ONLY A FEW DECADES AGO; LOOK AT THIS IRIDIUM SPIKE THAT OCCURED AROUND THE EXTINCTION OF THE DINOSAURS! THAT ELEMENT IS UNCOMMON ON EARTH. COULD AN ASTEROID STRIKE CAUSE A SPIKE? WHAT PASSES FOR SCIENCE TODAY UNFORTUNATELY; I THINK MEXICO IS WARMER THAN ANTARCTICA BECAUSE OF MAN MADE CLIMATE CHANGE OR SOMETHING!