Rocks Flashcards
how are sedimentary rocks formed
rock fragments transported by water, wind or ice and get worn down, become grains
grains are deposited at bottom of rivers, lakes, seas, becomes sediment
layer of sediment collect on bed and bottom layer squash
the grains are forced close together (Compacted) and water is squeezed out
minerals from water glue grains together (Cementation)
sedimentary rock is formed
igneous-what is molten rock called
magma
igneous-what is lava
molten rock flowing out of volcanoes
when are igneous rocks formed
when magma cools down
Igneous- when are small crystals formed
when lava cools down quite quickly and forms rocks like basalt
Igneous-when are large crystals formed
magma underground cools down much more slowly and forms rocks like granite
how can sedimentary or igneous rocks be changed to metamorphic rocks
by heat or pressure
examples of sedimentary rocks
limestone, sandstone, mudstone, chalk
examples of igneous rocks
basalt, granite
examples of metamorphic rocks
marble, quartzite, slate, schist, gneiss
sedimentary - grains or crystals
separate grains
igneous - grains or crystals
crystals that are not lined up
metamorphic - grains or crystals
crystals. often line up or in bands of different colour
sedimentary - hard or soft
often soft or crumbly
igneous - hard or soft
hard
