Amazing Facts About Rocks! By Chelsea McPherson Adapted by Chelsea Downie, Katie DiRe, Becky Ruddy, Kelly Schultz, and Holly Im-Hamper

A geologist is a scientist who studies rocks and earth materials. They use a hammer to separate rocks and look at the different layers. They use a magnifying glass or a microscope to better observe the properties. What is a person called who studies rocks?

How are rocks formed? One way rocks are formed is from lava coming out of an erupting volcano. When the lava hardens, it separates and forms 3 different rocks. They are basalt, tuff, and scoria. Two properties of basalt are gray and smooth. Basalt comes from the lava. Properties of tuff are white and dusty and it comes from the ashes of a volcano.

Scoria comes from the bubbly lava and its properties are red and rough. Can you see all the holes? Another way rocks are formed is by erosion. Erosion is when the wind, the rain, and the sun break away the earth’s surface and make rocks over time.

Erosion turns a boulder into a cobble. Erosion turns a cobble into a pebble. Erosion turns a pebble into gravel.

Erosion turns gravel into sand. Erosion turns sand into silt. Erosion turns a silt into clay.

Can you name earth materials from biggest to smallest? A boulder is bigger than 2 hands. A cobble fits in your hand. A pebble is about the size of popcorn.

The next 4 are gravel, sand, silt and clay.