Final answer:
The nature of a volcanic eruption is determined by three factors: volcano shape, magma temperature, and atmospheric pressure. Volcano shape controls eruption style, magma temperature affects lava viscosity, and atmospheric pressure influences eruption intensity.
Step-by-step explanation:
The three factors that determine the nature of a volcanic eruption are volcano shape, magma temperature, and atmospheric pressure. Each factor plays a role in different aspects of the eruption.
- Volcano shape: Volcano shape controls the eruption style. For example, a volcano with steep sides and a narrow vent may have explosive eruptions, while a volcano with gentle slopes and a wide vent may have effusive eruptions.
- Magma temperature: Magma temperature affects lava viscosity. Higher temperature magmas have lower viscosity, resulting in more fluid lava flows, while lower temperature magmas have higher viscosity, resulting in more explosive eruptions.
- Atmospheric pressure: Atmospheric pressure influences eruption intensity. Lower pressure at higher elevations can result in more explosive eruptions, while higher pressure at lower elevations can result in less explosive eruptions.