سؤال قراءة ستيب محلول — فهم التفاصيل (تدريب 4430)

(1) Volcanologists constantly monitor any changes in levels of seismic activity on Vesuvius because they know that the increase of activity in the deep reservoir of magma causes both earth tremors and volcanic eruptions. Through measuring seismic activity, these scientists expect to predict an approaching eruption months before it happens. (2) The seismic activity of Mount Vesuvius happens again and again, and the longer the intervals between eruptions, the greater the next explosion will be. The frequent but low-level activity of Vesuvius in recent centuries has relieved the build-up of pressure. The catastrophic magnitude of the eruption of AD 79 was connected with the extended period of inactivity before it.