Igneous Rock Characteristics and Identification

The video tutorial explains igneous rocks, which form from cooled magma or lava. It covers how to identify them by texture and composition, discussing common textures like phaneritic, aphanitic, vesicular, glassy, and pyroclastic. The composition is categorized into felsic, intermediate, and mafic, with examples like granite and basalt. Exceptions to general rules are also highlighted.

What is the primary difference between magma and lava?

• Lava is solid rock, while magma is liquid.

• Lava is found above the Earth's surface, while magma is below.

• Magma is found above the Earth's surface, while lava is below.

• Magma is solid rock, while lava is liquid.

Which texture is characterized by visible crystals in igneous rocks?

• Phaneritic

• Glassy

• Vesicular

• Aphanitic

What does a vesicular texture in igneous rocks indicate?

• Presence of large crystals

• Presence of glassy surfaces

• Presence of small crystals

• Presence of holes or vesicles

Which texture resembles a piece of dark glass?

• Phaneritic

• Aphanitic

• Vesicular

• Glassy

What is the main component of felsic igneous rocks?

• High magnesium content

• High calcium content

• High silica content

• High iron content

Which color is typically associated with mafic igneous rocks?

• Light pink

• Dark green

• Pale yellow

• Bright red

What is the composition of a rock with an even distribution of light and dark minerals?

• Intermediate

• Mafic

• Felsic

• Ultramafic

Which igneous rock is identified as felsic and phaneritic?

• Basalt

• Obsidian

• Granite

• Pumice

What is the specific rock name for a mafic aphanitic igneous rock?

• Basalt

• Diorite

• Granite

• Rhyolite

How are igneous rocks identified?

• By their texture and composition

• By their weight

• By their color alone

• By their size