Lesson 62 of 84 · Earth Systems
Lesson⭐ 30 XP🌋 Rock RealmCaves and Sinkholes (Part 2)
Earth Systems.
🎯 Your mission
Master the concept. Use it tomorrow.
⚡ The twist
Today's mountain was yesterday's ocean floor.
Mind = Blown
🌋 There are 1,500 active volcanoes on Earth right now.
Make a hypothesis first
Guess: where will the water go first?
What You'll Learn
Sinkholes form when underground limestone dissolves, leaving a cavity that collapses. They are common in areas with karst topography where water slowly dissolves the bedrock.
Key Words
- earthquake
- volcano
Steps
Look at the vocabulary words and write a definition for each in your own words.
Test rock hardness using Mohs scale: try scratching rocks with your fingernail, a penny, and a nail. Rank them from softest to hardest.
Compare the before and after states.
Write your conclusion: did the results match your hypothesis? What would you change next time?
Check Your Understanding
Question 1
1 of 3What causes ocean tides?
Where you see this in real life
This is shaping the ground you walk on, slowly, every single day.
Stretch Challenge
Try this in real life this week.
Find a rock outside and try to guess how old it is.
For the dinner table
“What's the slowest change you can think of?”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
Share this experiment
Send it to a parent who's looking for a 10-minute kitchen science win.
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