EESA06 Lectures 4/5
1. Rocks vs minerals
2. 2. The rock cycle
3. 3. Sedimentary rocks
4. 4. Metamorphic rocks
5. 5. Igneous rocks
A mineral has a crystallized substance and is a building block of rocks. Rocks are made up of different
Outcrops: is a geological term referring to the appearance of bedrock or superficial deposits exposed at
the surface of the Earth.
Geophysics the use of instruments to image what is down in the earth. To get information about the
layers at depth. In a contaminated site for example, we need to know how far the contaminants have
We start with magma, it is the source or primary product. Then it melts to produce igneous rock etc.
-A rock is a naturally formed, consolidated material composed of grains of one or more minerals
-a mineral is a naturally occurring, in organic, crystalline solid that has a definite chemical composition.
They are the building blocks of rocks
Minerals: 4500 different types but...
-the most important group are the silicate minerals containing silicon and oxygen and accounts for 90%
of all minerals. A few minerals dominate e.g.
-quarts – (silica = SiO2 = silicon plus oxygen
-olivine (mg, Fe, SiO4)
-Pyroxenes (e.g. augite)
-Clay minerals such as kaolinite montmorillonite
-As magma cools, its chemistry changes.
-The dominant mineral is basalt is olivine
How do we identify different minerals?