Mass extinction?

We predict mass extinction due to certain impacts, and we expect such impacts to occasionally occur
Evidence for previous mass extinctions?
- There’s an Iridium layer in sediments 65 million yrs ago. Iridium is rare on Earth but more common in asteroids. Is this debris from an asteroid impact?
- Believe an impact like this would raise temps by 10 C worldwide.
- Soot in sediment layers from same era; from the fires/soot that are predicted for such an impact?
- Where’s the crater?

We predict mass extinction due to certain impacts, and we expect such impacts to occasionally occur