1.
In an active lava field, lava flows downhill in channels called ________.
Correct Answer
C. Lava tubes
Explanation
In an active lava field, lava flows downhill in channels called lava tubes. Lava tubes are formed when the outer layer of a lava flow cools and solidifies, while the inner lava continues to flow. This creates a tunnel-like structure through which the lava flows, protecting it from cooling too quickly and allowing it to travel further downhill. Lava tubes can range in size from small tunnels to large caverns, and they are commonly found in volcanic areas with basaltic lava flows.
2.
A _________ lies under a caldera.
Correct Answer
B. Magma chamber
Explanation
A magma chamber is a large underground pool of molten rock that lies beneath a volcano. It is the source of magma that erupts during volcanic activity. Calderas are large volcanic craters that form when a volcano collapses or explodes, often due to the emptying of the magma chamber. Therefore, it is logical to say that a magma chamber lies under a caldera.
3.
A _____ volcano is formed mostly by hot lava flowing down the sides of the mountain.
Correct Answer
A. Shield cone
Explanation
A shield cone volcano is formed mostly by hot lava flowing down the sides of the mountain. This type of volcano has a broad, gently sloping shape, resembling a warrior's shield. Shield cone volcanoes are typically formed by low-viscosity lava, which allows it to flow easily and cover large areas. As the lava flows, it cools and solidifies, building up the volcano over time. The lava from shield cone volcanoes tends to be less explosive compared to other types of volcanoes, resulting in a relatively calm eruption.
4.
A stone wind can cause:
Correct Answer
D. The destruction of trees
Explanation
A stone wind refers to a strong wind that carries stones or rocks with it. This can lead to the destruction of trees as the stones carried by the wind can hit and damage the trees, causing them to break or fall. The impact of the stones can break branches, uproot trees, or even completely destroy them. Therefore, a stone wind can be harmful to trees and cause their destruction.
5.
A volcano that has not erupted for 200 years is:
Correct Answer
B. Dormant
Explanation
A volcano that has not erupted for 200 years is considered dormant. Dormant volcanoes are those that have not erupted in a long time but still have the potential to erupt again in the future. While they are currently inactive, there is still some activity happening beneath the surface, such as the movement of magma. Therefore, a volcano that has not erupted for 200 years is best classified as dormant.