Earth Sciences 1022A/B Lecture Notes - Lecture 8: Muav Limestone, Bright Angel Shale, Unconformity
7 Dec 2015
School
Department
Course
Professor
Document Summary
Earth sciences 1022a lecture 8 geologic time. Radio metric dating: numeric dates, puts a number on a rock (how old it is) Relative dating: how it started, comparing one rock to another. Superposition: each bed is older than the one above, and younger than the one below o. Any given rock unit is going to be younger than rock underneath it, and older than the rock above it. Cross-cutting relations: a fault is younger than the rock it cuts, a rock is younger than the rock it cuts. Inclusions: inclusions are older than the rock containing them. Angular unconformity: between flat and tilted, eroded beds. Nonconformity: between flat beds on eroded igneous, metamorphic rock. Matching up of rock types, their position within the sequence, and fossils. Fossil succession: organisms evolved along distinct pathways through geologic time, left index fossils (find them on all continents, and each one has a limited time frame where they live)
