Week 1 Flashcards
Who discovered catastrophism
Bishop James usssher
Based on scripture
How old did ussher believe the earth was
4004 BC
Doctrine of catastrophism
Earths landforms were formed by catastrophic events over short period of time
Occurred due to unknown causes that are no longer present today or
Uniformitarianism
“Present is key to the past”
James Hutton
“Father of geology”
Says the earth is millions of years old
Published the theory of the earth
Who discovered uniformitarianism
James Hutton
Primary dating techniques
Relative: Age of one feature relative to another
Numerical: absolute age, (radiometric dating)
6 relative age dating principles
- Uniformitarianism
- Superposition
- Original horizontality
- Cross cutting relations
- Inclusions
- Fossil succession
Law of superposition
Youngest on top, we build up and don’t shove things in between
Original horizontality
Sedimentary deposits horizontally originally, flat layers first, if it is no longer horizontal, we know an event has happened to move them.
Cross cutting relations
If a rock cuts through another, you know that the one doing the cutting is younger
Principle of inclusions
The youngest includes pieces of the old layers
Principle of fossil succession
Fossils are arranged according to their age and document the evolution of life through time
Fossils are usually found in _____ rocks
Sedimentary- lime/sandstone, marine rocks
Index fossil
Fossils that lived over a short period of time, usually newer, more abundant. The most helpful ones are around for the shortest amount of time