Period (geology)

High school (ages 12+)
Environment & Earth

Name:

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/period-geology

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 hierarchical placement?Subdivision of an Era; contains Epochs and Ages
2. What is the correlation methods?Biostratigraphy, radiometric dating, magnetostratigraphy, and lithostratigraphy are used for global correlation
3. What is a geological period?A geological period is a long chapter in Earth's history defined by special layers of rock. It shows big changes in life and the planet.
4. How do scientists decide where one period ends and another begins?Scientists look at special rock layers called marker beds, like a sudden drop in a metal called iridium, or big changes in fossils, to decide where one period ends and another begins.

Chronostratigraphy: The branch of stratigraphy concerned with the age of rock strata and their relationship to time.
Biostratigraphy: The branch of paleontology that uses the fossil record to date and correlate rock layers.
Magnetostratigraphy: The study of the record of the Earth's magnetic field in rocks, used for dating and correlation.
Paleozoic Era: The earliest of the three geologic eras, spanning from 541 to 252 million years ago, characterized by the rise of marine life and early land plants.