Igneous Rocks and Volcanic Activity

What is the texture of obsidian?

• glassy

• phaneritic/course

• aphanitic/fine

What is the texture of granite?

• glassy

• phaneritic/course

• aphanitic/fine

What is the texture of rhyolite?

• glassy

• phaneritic/course

• aphanitic/fine

What is the composition of rocks that have a high silica content?

• felsic

• intermediate

• mafic

What is the composition of rocks that have a low silica content?

• felsic

• intermediate

• mafic

How does silica affect viscosity?

• high silica = high viscosity

• high silica = low viscosity

Which terms go together?

• felsic - high silica - high viscosity

• mafic - high silica - low viscosity

• felsic - low silica - high viscosity

• mafic - low silica - high viscosity

Which mineral is the first to crystallize?

• olivine

• pyroxene

• quartz

• muscovite mica

Which mineral is NOT found in granite?

• quartz

• muscovite mica

• feldspar

• pyroxene

Tags

NGSS.MS-PS1-1

Which type of volcano has broad sides and basaltic magma?

• cinder cone

• shield

• stratovolcano