EESA06H3 Lecture 6: Planet Earth Final Notes
Document Summary
And a lot of geology is made up of book-like arrangements of rock layers. And if they contain fossils, we can put them in a relative age. And if we have absolute ages we can put actual page numbers on it. They have specific names like cambrian, pre-cambrian, ordovician. That way it usually floods with water and we can accumulate sediment (accommodation: opposite of subsidence is uplift. Long periods of boring inactivity, and then very brief episodes of absolute terror: fossils are the fossilized, lithified remains of an organism and organisms evolve through time. So, if we look at any one fossil type and compare that with other types elsewhere, we can usually put them in some sort of relative age position. The rate at which these isotopes break down is known. Uranium 238 is unstable and it breaks down by radioactive decay and the end daughter product is lead, pb.
