Why Do Rocks Get Holes By the Sea?

What Crafty Clover says in this video

Intro

Hey there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why do rocks get holes by the sea?

The Big Idea

Waves throw sand and pebbles at rocks. Soft spots wear away first. Some animals also drill tiny homes in the rock. Over thousands of years, a small dent can grow into a cave.

Waves Carry Grit

Step one: waves carry grit. Waves pick up sand and tiny stones. They throw that grit at the rocks again and again. The grit works like sandpaper, rubbing the rock a tiny bit each time.

Soft Spots Wear Away

Step two: soft spots wear away. Not all rock is equally hard. Soft or cracked spots wear down first and form a small hollow. Softer rocks, such as limestone and sandstone, wear away faster than hard granite.

A Hollow Grows

Step three: the hollow grows. Swirling water and grit keep scraping it deeper. Some animals move into the holes, and a few, like piddock clams, drill their own. A piddock clam uses its rough shell edge to scrape a neat round room.

A Closer Look

Let's take a closer look at a rock hole! A wave brings in water. The sand grit does the scraping. This makes a worn hollow. And a piddock hole is a neat round room.

Quick Facts

Quick facts! Do not put fingers in mystery holes, since animals may live there. Holey sea rock can be sharp and slippery. A piddock clam can bore a neat, round room. This takes a very long time.

Think Like a Scientist

Now, think like a scientist! Rub a piece of soft chalk with sand on a sidewalk. Look at what happens to the chalk. Try a hard stone, too. Why do some rocks get holes faster than others? Scientists notice differences and ask why. Happy exploring!

Outro

The sea drills with water and leftover sand! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!