How would you describe a stratovolcano?

How would you describe a stratovolcano?

• A. A volcano with a flat top formed by many lava flows
• B. A tall volcano made of layers of hardened lava and tephra
• C. A small, dome-shaped hill of solidified lava
• D. A volcanic feature that forms underwater

Answer: (B)

A stratovolcano is characterized as a tall, steep-sided volcanic structure formed from alternating layers of hardened lava flows and fragments of volcanic rock, known as tephra. The layering results from the explosive eruptions typical of stratovolcanoes, which eject volcanic ash, pumice, and other pyroclastic material alongside more fluid lava. This composite formation is what gives stratovolcanoes their distinct and prominent conical shape. The nature of their eruptions is often violent due to the high viscosity of the magma, which can trap gas and lead to explosive volcanic activity. This sets them apart from other types of volcanoes, such as shield volcanoes that have gentle slopes and are primarily built from low-viscosity lava flows. In contrast, other options present different types of volcanic formations or characteristics that do not apply to stratovolcanoes. For instance, a flat-topped volcano is more consistent with a shield volcano, a dome-shaped hill relates to volcanic domes, and underwater volcanic features represent seamounts or other submerged volcanic systems rather than stratovolcanoes.

A stratovolcano is characterized as a tall, steep-sided volcanic structure formed from alternating layers of hardened lava flows and fragments of volcanic rock, known as tephra. The layering results from the explosive eruptions typical of stratovolcanoes, which eject volcanic ash, pumice, and other pyroclastic material alongside more fluid lava. This composite formation is what gives stratovolcanoes their distinct and prominent conical shape.

The nature of their eruptions is often violent due to the high viscosity of the magma, which can trap gas and lead to explosive volcanic activity. This sets them apart from other types of volcanoes, such as shield volcanoes that have gentle slopes and are primarily built from low-viscosity lava flows.

In contrast, other options present different types of volcanic formations or characteristics that do not apply to stratovolcanoes. For instance, a flat-topped volcano is more consistent with a shield volcano, a dome-shaped hill relates to volcanic domes, and underwater volcanic features represent seamounts or other submerged volcanic systems rather than stratovolcanoes.