NAME
(Examples)
|
CAUSE
|
LOCATION
|
CHARACTERISTICS
|
Sedimentary
limestone;
sandstone; chalk; coal; rock salt; shale; dolomite; conglomerate
|
created
when layers of sediment (mud, sand, gravel and minerals) settle to the
bottom of the ocean and then compacted (pressed together) over thousands
of years
|
where
oceans or bodies of water once existed or still exist
|
soft,
layered, may contain fossils
|
Igneous
quartz;
pumice; granite; basalt; obsidian
|
created
when molten rock (lava) inside the Earth pushes through the crust (like
in a volcanic eruption) and then cools
|
where
volcanoes have or do exist
|
crystalline,
glossy, coarse-grained
|
Metamorphic
marble;
slate; gneiss; schist; quartzite; eclogite
|
created
when sedimentary or igneous rocks undergo metamorphosis (change) caused
by pressure, heat, and water acting on the rocks
|
deep
within the earth (where pressure and heat have a very large affect)
|
hard,
may contain bands or layers, may contain crystals
|
