The Red Soil of Malawi EarthCache

This is an Earthcache, not a physical geocache- there is nothing to find here! To claim and Earthcache you must visit the site using the listed coordinates and answer some questions about the earth science that you find there. Please email your answers to me before claiming the find. Any logs which have not had the go-ahead from me may be deleted!

The predominant colour of the soil across sub-Sararan Africa is red. Soil color is influenced by the amount of proteins or minerals present in the soil. Red soil can indicate the presence of iron oxides, and such soils are often known as ferrasoils for this reason. Such ground is sometimes called called laterite and is a clay which has been enriched with Iron and aluminium that has been developed over long periods of time by the heavy rainfalls and the intense heat.

Sometimes the material is rock hard but when scuffed by vehicle wheels it becomes a choking red dust. Many of the buildings in the area are made from this clay. Bricks are formed from the red clay/mud and are then fired in a makeshift kiln, making them durable and ready to use in single-storey buildings. It is the red colour of the soil which is reprented by the red band on the Malawian national flag.

There are countless places where you can see this soil- just look around you! So this location is just one of the accessible areas that I have regularly passed while living nearby. Feel free to make observations at any suitable location nearby and mention this in your post. All questions must be answered before you will be allowed to log. Please email the answers to the following questions before logging your "find". I will try and respond as soon as I can, web access permitting!

1) What is the chemical process that causes the iron content of the soil to turn red?
2) What is the approximate height (feet or metres) of the red soil bank at GZ?
3) Take a small sample of the red soil. Miix it with water ina clear, sealed container or jar and allow to settle. What do you notice about the order of colour bandings? Suggest a reason why this happens.
4) (Optional) Upload a photo of you and/or your GPS at the coordinates or by any area that clearly shows the soil colouration (But don't spoil Q3!)
 

I have earned GSA's highest level: