Earth and the Universe Flashcards
How are igneous rocks created?
Igneous rocks are magma which are either intrusive or extrusive.
Extrusive igneous rock cools quickly and has small crystals.
Intrusive igneous rock cools slowly and has large crystals
How are sedimentary rocks formed?
Sedimentary rocks are formed from lots of different small pieces of rocks under pressure of the sea
How are metamorphic rocks formed?
They are formed from sedimentary rocks under high pressure and heat from the earth’s crust
Give an example of a sedimentary rock
Sandstone, mudstone, limestone, shale
Give an example of a metamorphic rock
Marble, slate, quartzite
Give an example of an igneous rock
Obsidian, basalt, granite
How do fossils form
The organism dies and is covered by sediment
Minerals permeate the sediment to crystallise the remains.
The fossil eventually reaches the surface
What is the rock cycle
A cycle which shows how rocks change forms over time
How does the rock cycle work
Bits of sediment break down from erosion and weathering. They are then compacted down in the sea and form sedimentary rocks. The sedimentary rocks the go deeper in the earth, where it is hotter and with more pressure form metamorphic rock. If the metamorphic rocks go near a volcano’s magma chamber, they can turn into igneous rocks.
What is an intrusive rock
An igneous rock formed inside the earth
What is an extrusive rock
An igneous rock formed outside the earth
Name the three types of weathering
Chemical
Physical
Biological
Do intrusive rocks have large or small crystals
Large
Do extrusive rocks have large or small crystals
Small
Name the 4 types of erosion
Hydraulic action, abrasion, attrition, solution
