Eruption Columns, Such as the One Pictured Above, Are Unstable

question 100

Multiple Choice

Eruption columns, such as the one pictured above, are unstable and often collapse towards the Ground because_______ .

• A) they consist mostly of gases, which can cool and descend
• B) they are mostly large pyroclastics and these cannot be supported by rising air
• C) they are propelled by the eruption, as in the case of Pompeii
• D) they are mostly liquid lava flows being lifted by updrafts

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Definitions:

Sartorius

The longest muscle in the human body, running from the hip to the knee, and aiding in flexing, abduction, and lateral rotation of the thigh.

Biceps Femoris

A muscle of the thigh located at the back of the leg, part of the hamstrings group, involved in knee flexion and thigh extension.

Gastrocnemius

A major muscle located in the back part of the lower leg that helps in bending the knee and pushing the foot down, such as when walking or jumping.

Tibialis Anterior

A muscle in the lower leg that dorsiflexes and inverts the foot.