| A | B |
|---|
| Nonexplosive Eruptions | produce calm lava flows |
| Explosive Eruptions | produce pyroclastic flows |
| Lava | Magma above the surface |
| Magma | Molten rock below the Earth's Surface |
| Lava with high viscosity | thick like syrup |
| Lava with low viscosity | runny like water |
| Cinder Cone volcano | formed by layers of pyroclastic material |
| Shield Volcano | formed by layers of calm lava flows |
| Composite Volcano | Fomed by alternating layers of pyroclastic material and calm lava flows |
| Magma Chamber | where molten rock gathers deep underground |
| When water & gas content of magma is high | explosive eruption will occur |
| When the water and gas content of magma is low | a nonexplosive eruption will occur |
| Viscosity | a fluid's tendency to flow |
| Types of pyroclastic material | bombs, blocks, ash, lapilli |
| Types of lava | aa, pahoehoe, pillow, blocky |
| Caldera | the depression created when the roof of a magma chamber collapses |
| Crater | a funnel shaped pit near the top of the central vent of a volcano |
| Mid ocean ridges have volcanoes that occur along this type of plate boundary | divergent boundaries |
| Pyroclastic material forms when | magma explodes into the air and hardens |
| Climate change caused by volcanic eruptions | ash in the atmosphere blocks sunlight, causing temperatures to drop |
