The Rock Cycle Flashcards
Largest period of time
Eons
Amount of eons
4
Current eon
Phanerozoic
Second longest unit of time
Era
How many eras are there?
3
What era are we in?
Cenozoic
How long has the cenozoic era been?
66million years
What do eras reflect?
Noticiable changes in the Earths fossil record.
Second shortest period of time
Periods
What do periods show?
When a single type of rock was formed
Smallest unit
Epoch
What epoch are we in?
Holocene/anthropocene
What are the three types of rock
Igneous, metamorphic, and sedimentary
How is igneous rock formed?
When rocks melt into magma and then cool.
How are sedimentary rocks formed?
When rocks are weathered and eroded into sediment and compressed by layers of sand.
How are metamorphic rocks formed?
When rocks are transformed by heat or pressure
What are examples of igneous rock?
Granite
What is an example of a sedimentary rock?
Sandstone or limestone
What is an example of a metamorphic rock?
Marble
Where are igneous rocks found?
Mountains and continental outcrops
Where are sedimentary rocks found?
Oceans, deserts, and lakes.
Where are metamorphic rocks found?
Underground, in quarries.