Tonian

High school (ages 12+)
History & Culture

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Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/tonian

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the geological era?Neoproterozoic Era (first period)
2. What is the chronometric boundaries?1000 Mya to 720 Mya
3. What was the Tonian period?The Tonian was a very long time ago, from 1000 to 720 million years ago, when Earth was changing a lot. It was the first part of the Neoproterozoic Era and set the stage for later big changes.
4. Why is the Tonian called the "stretch"?Its name comes from the Greek word for stretch, because the supercontinent Rodinia began to pull apart and stretch during this time.

Neoproterozoic Era: The most recent era of the Proterozoic Eon, spanning from 1 billion to 541 million years ago, characterized by significant geological and biological evolution.
Radiometric Chronometry: A scientific technique for determining the age of materials by measuring the decay of radioactive isotopes, providing precise temporal markers for geological events.
Rodinia: A hypothesized supercontinent that existed during the Neoproterozoic and Mesoproterozoic eras, which began to break apart during the Tonian period.
Plate Tectonics: The scientific theory describing the large-scale motion of Earth's lithosphere, which is divided into tectonic plates that move over the asthenosphere.