Rock Type Review

Rock Texture: Small crystals, glassy texture
Rock Type: __________
Examples:____________

• Extrusive; Pumice, Obsidian
• Intrusive; Pumice, Obsidian
• Extrusive; Granite, Pegmatite
• Intrusive; Scoria, Basalt

Rock Texture: Large crystals, coarse grained
Type of Rock:______________
Examples:_________________

• Extrusive; Pumice, Obsidian
• Intrusive; Scoria, Pumice
• Extrusive; Granite, Pegmatite
• Intrusive; Granite, Gabbro

What Should be placed in the box labeled 1?

• Sedimentary Rock
• Igneous Rock
• Metamorphic Rock
• Sediments

Box number 5 represents --

• Metamorphic rock
• Sedimentary rock
• Igneous rock
• Molten rock

Rock layers tell a story about their past.  What is the basic assumption that is made when reading this story?

• The composition of the Earth's atmosphere has been constant.
• The processes in the rock cycle were the same in the past as they are today.
• The Earth's crust cooled and then remelted before rock layers began to form.
• Chemical reactions in the past were slower than they are today.

Obsidian, Pumice, and Scoria lack crystals because-

• They cooled too slowly
• They cooled deep inside Earth
• Not enough minerals were present where they formed
• They cooled too quickly

The rock shown is composed primarily of large crystals that were formed by-

• cooling magma
• faulting
• weathering
• compacting shells

Of these igneous rocks, which would contain the largest crystals?

• Obsidian
• Granite 
• Rhyolite
• Pumice

What does box number 2 represent?

• Metamorphic rock
• Sedimentary rock
• Igneous rock
• Sediment

What should be placed in the box labeled 3?

• Sedimentary rock
• Igneous rock
• Sediment
• Metamorphic rock