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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.
"Plates tect2 en" by USGS. Licensed under Public domain via Wikimedia Commons

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?

  • leaf green style avatar for user Elkia
    Will the continents come back together like in the past?
    (6 votes)
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    • duskpin ultimate style avatar for user Betty :)
      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).
      (6 votes)
  • orange juice squid orange style avatar for user Suchi Jain
    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)
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  • duskpin seedling style avatar for user rlavasseurstudent
    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.
    (3 votes)
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  • starky tree style avatar for user KcadenK
    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)
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  • spunky sam green style avatar for user Sabrina Groom
    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)
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  • blobby green style avatar for user Anna  Ignateva
    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)
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  • blobby green style avatar for user Kihran.Mcferrin
    yes there are two tectonic plates because there have been multiple claims throughout the years of two tectonic plates colliding together creating mountains and other land masses because of there collision.
    (1 vote)
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  • blobby green style avatar for user Hannah.Wagers
    I pick the claim that states, Historians, and geologists measure time in very different ways. I believe it is true. I believe it is true because in a video we watched for the assignment the speaker said it.
    (1 vote)
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  • duskpin seedling style avatar for user rlavasseurstudent
    stars are a form of gas that burns out eventualy because the gas catches fire
    (1 vote)
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  • spunky sam blue style avatar for user kaneesha kirkland
    I do believe that historians and geologist measure time in different ways, however do you think that do to the fact that we all live in different continent that our time will be measure differently. also with the sun rotating or us rotating around the sun its hard for all of us to get that morning or sun glow which make us tell time differently then form someone who lives a thousands miles away or more.
    (1 vote)
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