Volcanoes: Cinder, Composite, and Shield

What is the primary material ejected from cinder cone volcanoes during an eruption?

• Lava flows

• Ash and dust

• Large rocks

• Volcanic bombs and lapilli

How do cinder cone volcanoes typically form?

• Through the accumulation of hardened lava

• By the buildup of volcanic ash layers

• Through the piling up of volcanic bombs, lapilli, and ash around a vent

• By the cooling of a large magma chamber

What is a distinctive feature of composite volcanoes?

• They are flat and spread out

• They consist entirely of volcanic ash

• They have steep slopes and a conical shape

• They are small with a wide base

Composite volcanoes are made up of alternating layers of what materials?

• Lava and ice

• Lava flows and volcanic ash

• Sand and gravel

• Mud and volcanic bombs

What triggers the eruptions of shield volcanoes?

• High gas content in magma

• Sudden cooling of magma

• Low viscosity lava

• High pressure from the Earth's crust

What is the shape of shield volcanoes?

• Tall and narrow

• Small and round

• Broad and low

• Steep and conical

How do shield volcanoes typically erupt?

• Explosively, with lots of ash and gas

• Gently, with lava flows spreading over large areas

• With a single, catastrophic explosion

• Intermittently, with periods of quiet and sudden bursts

What type of lava is most commonly associated with shield volcanoes?

• Andesitic

• Rhyolitic

• Basaltic

• Dacitic

Which type of volcano is typically the smallest?

• Cinder cone

• Composite

• Shield

• Lava dome

What is the main cause of the explosive eruptions seen in composite volcanoes?

• Low gas content in magma

• High viscosity of magma

• Low viscosity of magma

• High temperature of magma