Download Rock Cycle

A. Rock Cycle
A sequence of events involving the formation,
destruction, alteration, and reformation of rocks.
Grand canyon
B. Types of Rocks
1. Igneous Rocks (igneous means formed by fire)
Formed by cooling magma
95% of the Earth’s crust
Most common – granite and basalt
Intrusive – formed beneath Earth’s surface
Extrusive – formed at Earth’s surface
1. Igneous Rocks (igneous means formed by fire)
granite
basalt
obsidian
pumice
B. Types of Rocks
2. Sedimentary Rocks (weathered material)
Found in upper portion of crust
Sediments – accumulated weathered material
carried by water, wind, or ice
Most common – sandstone, shale, and limestone
Weathering – breakdown of rocks into smaller pieces
Erosion – transport of rocks from one place to another
2. Sedimentary Rocks (weathered material)
sandstone
limestone
shale
siltstone
B. Types of Rocks
3. Metamorphic Rock (metamorphic means changed in form)
Formed from pre-existing rocks that are
transformed by high temperatures, high pressures,
or both without melting
Most common – marble and slate
3. Metamorphic Rock (metamorphic means changed in form)
marble
quartzite
slate
Mica schist
C. Rocks are made of minerals
Minerals – naturally formed, generally inorganic,
crystalline solid composed of an ordered array of atoms
having a specific chemical composition
Some such as gold are composed of single elements
Most minerals are compounds
Most minerals are distinguished by their physical
characteristics – crystal form, hardness, cleavage,
luster, color, streak, and specific gravity
Most Common Minerals – Silicates
Feldspars and quartz are the most common silicates
Silicates contain oxygen and silicon which make up
46.6% and 27.7% of the Earth’s crust – 95% of the
continental crust is made up of feldspar and quartz
feldspar (orthoclase), KAlSi3O8
quartz (amethyst), SiO2
2nd Most Common Minerals – carbonates
The carbonate ion (CO32-) can bond with a variety of
other ions to produce the carbonate minerals.
Calcite is the most common carbonate. All carbonate
dissolve easily in acidic water
calcite (CaCO3)
azurite (Cu3(CO3)2(OH)2)
malachite (Cu2CO3(OH)2)
Other Common Minerals – oxides and sulfides
Oxides
O-2 ions
corundum (Al2O3)
magnetite (Fe3O4)
Sulfides
S-2 ions
galena (PbS)
millerite (NiS)