GEOL 1 Lecture Notes - Lecture 16: Sequence Stratigraphy, Unconformity, Nonconformist
Document Summary
Important when we want to ask how old something is or when something happened. Dating methods: relative put events into a sequence, find age relative to other events, absolute quantitative, how long ago from today, very complicated and expensive. Fossils any evidence of past life. Stratigraphy studying strata (layers of rock) if we know the age of strata we know the age of any fossils inside. Unconformities gaps in time within strata. Sediment runs out so there is nothing to deposit to form new layers. Disconformity different types of sedimentary rocks both below and above gap. Nonconformity sedimentary rock on one side of gap and igneous or metamorphic on the other. Angular nonconformity layers below are tilted, layers above are horizontal, takes a long time to form. Identification - difficult to tell what type. Duration difficult to tell how much time is missing. Stratigraphic principles that gets cut through is the oldest, what did the cutting is younger.