Cretaceous–Paleogene extinction event

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/cretaceouspaleogene-extinction-event

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 marker?The K-Pg boundary layer, rich in iridium
2. What is the impact crater?Chicxulub crater, approximately 112 miles (180 km) in diameter
3. What happened during the Cretaceous–Paleogene extinction event?A huge space rock hit Earth about 66 million years ago, causing big earthquakes, fires, tsunamis, and a long dark winter that killed many dinosaurs and other species.
4. Why is there a special layer of dirt called the K‑Pg boundary?The layer is filled with a rare metal called iridium, which is common in space rocks but rare on Earth, showing that an asteroid hit the planet.

Adaptive Radiation: The rapid diversification of a lineage into new forms and species to fill available ecological niches.
Iridium Anomaly: An unusually high concentration of the element iridium in a geological layer, often indicating an extraterrestrial impact.
Deccan Traps: A large igneous province in India, formed by massive volcanic eruptions around the time of the K-Pg extinction.