Igneous Rocks Flashcards
What are the 3 classifications of rock types?
Igneous, sedimentary, and metamorphic
Igneous rocks form from cooling magma. What is significant about igneous rocks?
They are the only rocks we can date
How are sedimentary rocks formed:
through lithification of rock fragments
Metamorphic rocks are:
pre-existing rocks that are altered by heat and pressure.
Igneous rocks have two types of texture:
intrusive and extrusive
What does the intrusive texture type of an igneous rock mean:
cooled beneath the surface, cooled slowly, coarse(large) grained, CRYSTALS present
what does the extrusive texture type of an igneous rock mean:
cooled above surface, cooled quick, NO CRYSTALS
What are the two types of composition of igneous rocks?
Felsic and Mafic
Why are igneous rocks more resistant to weathering or erosion?
because they are high in silica
What is a batholith?
magma chamber
What is a sill?
is a horizontal break in the layers in which lava can rise.
What is a dike?
is a perpendicular or vertical pockets in the earth’s layers in which lava can flow.
Laccolith is:
an injection that’ stretching trying to get through the earth’s layers
Why do mountains appear larger than everything around them?
Because the mountains are high in silica and are weathered and eroded slow that the softer ground around it, which is worn down.
