This preview shows page 1. Sign up to view the full content.
Unformatted text preview: - going to diff places of country, similar countries
- same period of time
- time ranges of species over lap, look at various species Fossils that are
particularly useful for
this purpose are called
index fossils. - bottom = primitive earlier species
- something that existed for a short time, more useful in terms of dating rocks 3 1/25/2013 - rocks erode, losing time (gap in time, rock goes missing) Missing Time and Unconformities
The rate of sediment deposition is not uniform through time.
Significant pauses in sediment deposition may occur, or in extreme cases,
rock can be removed by erosion. - this unconformity is famous in Scotland Under these circumstances, “time” (in the form of rock) goes missing. - tilted by crunching of layers, wearing down of rocks Surfaces representing these slices of missing time are called
Horizontal sedimentary rocks horizontal sedimentary rock
Example of an
unconformity Tilted sedimentary rocks tilted sedimentary rocks Example of How These Relative Dating
Principles Can Be Used - relative time of events picture for test?
- faulting, erosion, layers ontop, faulting, erosion to level 11 Dealing With Absolute Time
Use knowledge of the behaviour of radioactive materials to
date minerals, rocks and geologic events (specifically the
behaviour of decay in radioactive isotopes of certain
elements) (same protons, diff number of neutrons) Radioactive Isotopes: Varieties of atoms of a particular
element differing in their number of neutrons and having the
ability to spontaneously decay to produce daughter products
and energy. 4 1/25/2013 ratio of parent iso...
View Full Document
This document was uploaded on 02/25/2014.
- Fall '14