EESA01H3 Lecture Notes - Lecture 8: Decay Product, Radiometric Dating, Absolute Dating
Document Summary
Based on mapping of rock layers you say that this one is older than the other one. Stratigraphy: the sub discipline of geology concerned with age of rocks. If they contain fossils, then we can find the relative age. Absolute dating methods can find exactly where we are in the story of earth history. Accommodation: in order to get rocks preserved we need areas of the crust that are subsiding. We need the crust to be sinking over broad areas and these are called sedimentary basins. Uplifting: results in non-accommodation, erosion and removal of sediment and rock index fossils used to define and identify geologic periods. Conformable succession: layers on top of another without breaks. Unconformable succession: major time breaks within a succession, more gaps tha(cid:374) re(cid:272)ords. There s (cid:373)ore ti(cid:373)e that are u(cid:374)re(cid:272)orded (cid:271)y ro(cid:272)ks tha(cid:374) a(cid:272)tually recorded. Brittle rocks: happens where rocks are cold and cause faults. Isotope dating: rate at which these unstable isotopes breakdown is known.
