Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
RELATIVE VS. ABSOLUTE DATING
Transcript of RELATIVE VS. ABSOLUTE DATING
A method of determining whether an event or object is younger or older than another event or object.
I have been teaching at WMS for 2
. This is exact.
I am younger than my brother. My brother is 34. This relative. You know that I am younger than 34 years old.
FORCES THAT CHANGE THE EARTH
UNIFORMITARIANISM VS. CATASTROPHISM
The same geologic processes that are happening today are the same processes that have been shaping the Earth throughout its history.
The principle that states that all geologic changes occurs suddenly.
This principle was stated by James Hutton about 250 years ago
Before Uniformatarianism, this was the principle that most scientists believed.
A HAPPY MEDIUM
Today, scientists believe that both principles affect our Earth. Although most geological processes occur slowly, Earth does experience sudden geologic events.
THE PRINCIPLE OF SUPERPOSITION
Younger rocks lie above older rocks in undisturbed sequences.
When a rock layer is missing.
At some future time deposition begins again.
Where sedimentary rock layers lie on top of an eroded surface of nonlayered igneous or metamorphic.
Exists between horizontal rock layers and rock layers that are tilted or folded.
Watch the following video. It is an excellent example of unconformities and the 3 main categories.
NOW LET'S PRACTICE FIGURING OUT WHICH LAYERS ARE THE YOUNGEST AND OLDEST. ON A PIECE OF PAPER, PUT THE LAYERS IN ORDER FROM OLDEST TO YOUNGEST.
The answers will be on the next section.
Picture # 1
Oldest to youngest
Oldest to youngest
Click on the link below to view "What is Relative Dating?"
of an event or object in
Method of finding out the
of an object by figuring out the ratio of
To determine absolute age, scientists look at the breaking down of an
isotope into a
that has a different number of
than other atoms of the same element.
Most isotopes are stable, but some are unstable. We call them
. These isotopes break down, trying to become stable. This is called
. The rate of decay is constant.
The unstable isotope is called the
isotope that is produced is the
LET ME TELL YOU A STORY. THIS IS A STORY ABOUT MR. & MRS. ISOTOPE AND THIER DAUGHTERS. CLICK ON THE VIDEO BELOW TO LEARN MORE ABOUT THIS VERY UNSTABLE FAMILY.
The amount of time it takes for half of the radioactive sample to decay. In other words, the amount of time it takes for half the parent material to decay.
Unconformities are disturbances in the rock layers. Intrusions and faults throw off the consistent pattern of superposition
RELATIVE DATING ABSOLUTE DATING
Finding out whether an object is older or
younger than another object.
Not specific or exact.
Finding the age of an object.
THE GEOLOGIC COLUMN
Like I said before not all rock layers are in nice neat rows. Because of disturbing forces, the disruption in the rock layer sequence can be a challenge for geologists.
Geologists combine data from all know undisturbed rock sequences from around the world to create an ideal sequence of rock called the
- What is an example of a TRACE fossil?
- What can be fossilized?
- Take a seat. Take out a pen/pencil and a sheet of paper you recieved when entering the class
- Put your first and last name and the date
TASK: BE PREPARED TO SHARE!!!!
Read "T.Rex's Tiny Arms" on page 4 of ScienceWorld magazine
What is the main question of this article?
How long were T. Rex's arms on average?
Do you think that T. Rex used it's arms based on the fossil evidence?
- Which type of fossil creates an impression or indention?
- Which era of time do we currently exist in?
- What information can we gain from studying fossils?