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Course: Big History Project > Unit 4
Lesson 4: Ways of Knowing: Our Solar System and Earth | 4.3- ACTIVITY: DQ Notebook 4.3
- WATCH: Introduction to Geology
- READ: Alfred Wegener and Harry Hess
- ACTIVITY: Claim Testing – Geology and the Earth’s Formation
- READ: A Girl Talk Geological Revolution - Marie Tharp: Graphic Biography
- READ: Eratosthenes of Cyrene
- WATCH: Introduction to the Geologic Time Chart
- READ: Principles of Geology
- ACTIVITY: What Do You Know? What Do You Ask?
- READ: The Universe Through a Pinhole — Hasan Ibn al-Haytham
- READ: Gallery — Geology
- Quiz: Our Solar System and Earth
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ACTIVITY: Claim Testing – Geology and the Earth’s Formation
Purpose
This activity will help you review the four claims testers and understand how scientists would use them to investigate claims about plate tectonics.
Process
Remember that we are presented with claims in everyday life. Your job in this activity is to evaluate the following claims:
- About 99 percent of the matter in any star-forming gas cloud ends up in a star, and only about 1 percent is left over for planet formation.
- Differentiation is the process by which gravity in the disk spinning around a developing star clumps matter together into planets, asteroids, and other objects.
- Each continent has its own tectonic plate.
- Historians and geologists measure time in very different ways.
Pick one of these claims and decide whether you think it’s true or false. Then, decide what claim tester (intuition, evidence, logic, authority) helps support your assertion.
For Further Discussion
In the Question Area below, do two things:
1. Post your claim, whether you think the claim is true or false, and the claim tester that supports your assertion.
2. Look at someone else’s posting and see if you can find additional claim testers to support that person’s assertion. Respond to their post with the claim tester you’ve found and a description of how it supports their assertion.
Want to join the conversation?
Will the continents come back together like in the past?(8 votes)
Yes! Our seven continents are predicted to become another supercontinent in some of the following hundreds of millions of years. The plate tectonic supercycle reoccurs about once every 400 million years, with the last supercontinent being Pangea which broke up about 335 million years ago, when the dinosaurs were around. When the cycle restarts, it means that all of the oceanic lithospheric plates from the previous cycle would have been recycled (or subducted, melted, and reformed).(7 votes)
Hanane stars dont form there own gas. They just take gas from any thing it can get.The stars just burn off there gas and they try to get more gas so that they can live.(4 votes)
Each continent does not have its own tectonic plate. If you look in the picture, you see that Europe and Asia have a combined tectonic plate meaning that not every continent has its own tectonic plate.(4 votes)- You can test this claim by looking at the make-up of mountain ranges.(1 vote)
Why do we have earthquakes in the middle of continents?If every continent has its own plate , we would only have earthquakes at the plate boundaries(2 votes)
The continents are irregular and may have fault lines in various places due to weaknesses in the crust. One popular example of this is in Missouri: https://en.wikipedia.org/wiki/New_Madrid_Seismic_Zone
There is also human activity causing earthquakes. Fracking has led to a significant increase in seismic activity in previously stable places like Oklahoma. Also mega structures, like China's Three Gorges Dam, change the landscape significantly to also produce seismic activity.(4 votes)
Yes I do think that there are seperate plates my proof is that if all of the plates were to combine into one during the Earths creation then we would all be in a predicament every time there was an earthquake. Just imagine Japans 8.1,Wouldn't that have been an issue,answer......yes,and also states would count when having there own plate(3 votes)
Differentiation, the process of balls of gas and rocks turn into a disc, we can see this in action using telescopes and satellites! Even in our own solar system, we can see differentiation flatten the discs of Saturn and Neptune to name some.(2 votes)- No. Differentiation is the process of the materials of a melting planet being separated. The heavier materials like metals such as iron will sink to make the planets core while lighter and low-density magmas will rise up to create the crust of the planet. This process allows for the compositional layers of a planet to be created.(2 votes)
Each continent has its own tectonic plate.
I think this is false because if there were only 7 plates then we wouldn't have earthquakes of different plates where the earth quake happens colliding. If each continent had its own plate then we wouldn't get earthquakes in places that are in the center of continents.(2 votes)
Each continent does not have its own tectonic plate. Evidence shows that plates aren't the same size as their continent counterparts.(2 votes)- Differentiation is the process by which gravity in the disk spinning around a developing star clumps matter together into planets, asteroids, and other objects. I think it is true, we have the evidence of a similar process of separation of milk - when the milk is spinning in spechial equipment it is divided into different parts (butter, cream, serum).
Historians and geologists measure time in very different ways. I feel it is true though the authorities say that the way is the same, my intuition think the time is very strange thing and not only the way of measuring of it can be different, itself can be very different in different conditions.(1 vote)- Actually, differentiation is when the earth's layers formed by heavier elements sinking and lighter ones rising.
Accretion is when dust and gas spinning around the early star forms into planetary bodies through electrostatic forms and collisions.(2 votes)