Question

Explain why some volcanic eruptions are explosive and others effusive

Answer 1

Volcanic eruptions vary in explosiveness due to differences in magma composition and gas content. Explosive eruptions typically involve viscous magma with high gas content, causing pressure buildup, whereas effusive eruptions involve less viscous magma allowing gases to escape more easily, resulting in gentler lava flows.

Step-by-step explanation:

Volcanic eruptions vary in explosiveness due to differences in magma composition and gas content. Explosive eruptions typically involve viscous magma with high gas content, causing pressure buildup, whereas effusive eruptions involve less viscous magma allowing gases to escape more easily, resulting in gentler lava flows.

Answer 2

Volcanic eruptions can be either explosive or effusive. Explosive eruptions occur when there is a high gas content in the magma, resulting in an explosive release of ash, lava fragments, and gases. Effusive eruptions occur when the magma is low in gas content and flows steadily from the volcano.

Step-by-step explanation:

Volcanic eruptions can be either explosive or effusive depending on several factors. Explosive eruptions occur when there is a high content of gas, such as water vapor, carbon dioxide, and sulfur dioxide, in the magma. The gas expands rapidly when the magma reaches the surface, causing an explosive release of ash, lava fragments, and gases. These eruptions typically result in pyroclastic flows, ash clouds, and volcanic bombs.

On the other hand, effusive eruptions occur when the magma is low in gas content and flows steadily from the volcano. Lava effuses or spills out onto the surface, creating lava flows and forming shield volcanoes. These eruptions are generally less explosive and pose fewer hazards compared to explosive eruptions.