Oxidation--Chemical Weathering

This picture shows that chemical weathering has taken place by oxidation. When we used the rock hammer to chop into the cream colored clay layer in the bottom of the stream, we saw that the original color of the clay was blue. The blue color is a result of iron compounds containing ferrous iron. These compounds change to a cream color when the material reacts with oxygen in the atmosphere changing the iron to its ferric form. Changing iron from its ferrous form to its ferirc form is a typical oxidation chemical reaction.