Rocks to eat?

The latest Earthlearningidea is 'Rocks to eat? How we get the elements we need to stay healthy'. Like all living things, we need many chemical elements in order to be healthy. These elements come from minerals in the soil and the soil gets the minerals from the rocks beneath. This activity explores how these elements reach us and other living things.
Do please let us have feedback on this activity.

Cracking the clues

This activity is great fun to try - 'Cracking the clues: making your own cracking clues to the Earth's past'.
Your pupils may have noticed that, when a pool dries up, it often leaves a muddy bed, which cracks into regular shapes (polygons) as the wet mud shrinks. Therefore, ancient mudcracks show us that the area where they are found must have been mud that dried out in the past. It must have been surface mud rather than mud laid down under deep water. So the cracks are key clues to the conditions in which the mud was laid down.
Polygonal cracking in natural materials is caused by shrinkage and the shrinkage is caused either by drying out or by contraction on cooling.
Please let us know how you get on with this latest Earthlearningidea. Which method did you use?

Weathering

Click here to view the latest Earthlearningidea - 'Weathering - rocks breaking up and breaking down'. In this activity pupils are asked to match pictures and descriptions of weathered rocks with the processes of weathering that formed them.
Weathering occurs all around us, and in all climates. It affects construction materials as well as natural exposures of rocks. Weathering contributes to the concentration of economic resources, such as china clay and bauxite and is very important in the formation of soil. It probably plays a vital role in climate change as well.

ELI - October update

Since Earthlearningidea started in May 2007, we have had just over 8000 visits to the site from 112 countries. We have published maps showing the countries and cities where Earthlearningidea activities have been viewed. As you can see from the map, there is a large area in Africa that we have not reached. Can anyone help? Contact us via this blog or by email.

What controls the speed of a tsunami wave?

This our latest Earthlearningidea - click here. This activity investigates the relationship between the depth of water in a tank and the velocity of a water wave generated by lifting and then dropping one end of the tank.
Please try this activity with your pupils and let us know their results. What do they think affects the speed at which a tsunami travels? Will the wave travel faster or slower in shallow water than it does in deep water? Write your comments on this blog.

From Russia

The following has been sent to us from the Institute of Natural Science, Perm State University in Russia;-
"I am grateful for this project and that you send news regularly. I teach Environmental Geochemistry and Biogeochemistry in the Department of Geography in Perm State University and I have used some Earthlearningideas as examples of geological and biological processes. I also recommend your site to my students."
We are very pleased to hear news like this. Thank you.
The Earthlearningidea Team