What causes a big bulge to slowly grow on the flank of an active Cascades volcano?
A) Thick lava flows pile up around the vent.
B) A huge gas bubble released from the magma inflates it.
C) The magma reacts with snow on the volcano, causing magma inflation.
D) The hot magma melts older ash, causing it to expand.
E) Rising magma is pushing it up.

Question

Quizplus · Accepted Answer

The rising magma is pushing up the flank of the volcano, causing a bulge to slowly grow. This is a common precursor to volcanic eruptions and can be monitored by geologists to assess the potential for eruption.

What Causes a Big Bulge to Slowly Grow on the Flank