Igneous Rocks

Where is lava located?

• above ground

• below ground

• in the core

• in the mantle

Course Grained

• Pumice

• Obsidian

• Fast cooling, small grains, extrusive rock

• Slow cooling, big grains, intrusive rock

fast cooling magma

• greater acidity

• finer texture

• small or no crystals --> fine texture

• coarser texture

Example of extrusive rock with glassy texture.

• granite

• obsidian

• pumice

• basalt

What does the texture of the igneous rock depend on?

• when magma erupts onto earth's surface through a volcano or fissure (cracks in earths crus) and cools quickly

• LARGER crystals --> coarse texture

• above and below the earth

• how fast magma cooled

porous texture

• small or no crystals --> fine texture

• slow cooling, big grains, intrusive rock

• larger crystals --> coarse texture

• spongy appearance,rock due to rapid cooling (extrusive)

Where is igneous rock formed

• small or no crystals --> fine texture

• pumice

• granite

• above and below the earth

What happens when magma cools very slowly

• Finer texture

• Small or no crystals --> fine texture

• Obsidian

• LARGER crystals --> coarse texture

Fine Grained

• Fast cooling, small grains, extrusive rock

• Obsidian

• Slow cooling, big grains, intrusive rock

• Small or no crystals --> fine texture

Example of intrusive igneous rock.

• granite

• pumice

• obsidian

• basalt