Activity 4 - Graded sediment
Learning intention:
We are learning to understand how sediment settles out in water, and how we can use that to undertand how sedimentary rocks are formed.
Language
Graded - this means sorting from big to little. In school, students test marks are graded - they are sorted from highest to lowest. Fruit is graded - from biggest to smallest, or from best quality to fruit just for juice.
Sediment - usually pebbles, sand, mud, grit etc - that settles out from water.
Sedimentary rock - rock that is hardened pebbles, sand, mud, grit ...
Materials
Glass jar
Sand, mud, pebbles
Water
Activity
Mix up about one cup of sand, mud, and pebbles
Place it into a glass jar
Add enough water to nearly fill the jar
Put the lid on firmly
Shake for about 15 seconds
Take a close-up photo of the sediment in the jar (leave the lid on)
Leave the jar to settle overnight
Take a photo of the sediment the next morning
Look at some of the rock samples in th room - do any of them show grading of the sediment.
Follow up
Check out the photos of some of the graded sedimentary rocks: