Months of volcanic restlessness（不安定） preceded（在前面） the eruptions this spring of Icelandic volcano Eyjafjallajökull, providing insight into what roused（唤醒） it from its centuries of slumber（睡眠） . An international team of researchers analyzed geophysical（地球物理学的） changes in the long-dormant volcano leading up to its eruptions in March and April 2010. In a study published in the Nov. 18 issue of the journal Nature, the scientists suggest that magma（岩浆，糊剂） flowing beneath the volcano may have triggered its reawakening.

"Several months of unrest preceded the eruptions, with magma moving around downstairs in the plumbing and making noise in the form of earthquakes," says study co-author Kurt Feigl, a professor of geoscience at the University of Wisconsin-Madison. "By monitoring volcanoes, we can understand the processes that drive them to erupt."