GEOL 104 Lecture Notes - Lecture 19: Geologic Time Scale, Radiocarbon Dating, Radiometric Dating
18 Apr 2016
School
Course
Professor
Document Summary
Geol104 lecture 19 geological time/folding and faulting. Best way to see gaps in geological time. Disconformity: strata on either side parallel, all layer just one layer missing. Nonconformity: separates older metamorphic/igneous rock from younger sedimentary strata, correlation of rock layers. One package of rocks that can be followed all the way to. Theory breaks down: i. e. at beach as you get farther out from shore, change from sand to mud or reef, all deposited at same time but no longer physical correlation. Widely separated strata"s can be identified and correlation by distinctive fossil content. When you see certain fossils in rock (ex dinosaur) can give a relative time range. Principle of fossil succession: fossil organisms succeed each other, any time-interval can be recognized by its fossils. Index fossils: fossils are geographically widespread, limited to short span of time, presence allows us to match rock to specific time period. Dating with radioactivity: allows us to determine earth is approx.
