SCIENCE LAB SCARES : CALAMITY IN WAITING

' One catastrophe pinned down, in hopes of foreseeing the next ' : An outpouring of magma isn't the biggest risk to people living downhill from Mount Rainier in Washington.

The volcano's greatest danger comes from Lahars - amalgam of mud, rock and water that are as dense as wet concrete.

Over the past several thousand years at least nine large Lahars have barreled down the steep slopes of the 14, 410-foot [ 4, 392 meter ] mountain, sometimes reaching as far as the Puget Sound 60 miles [ 100 kilometres away.

The largest Lahar of the past 1,000 years was known as, Electron Mudflow, named for the small hamlet of Electron.

That event buried the nearby landscape in 20 feet of mud. But scientists have struggled to precisely date this event.

Knowing the year could make it possible to correlate the Lahar with other events and better predict future muddy outbursts.

The Electron Mudflow sent debris coursing up to 35 miles away, into what is now the small city of Orting.

Scientists believed that they could use dendrochronology, or the study of tree rings, to determine a more precise date.

That's because a Lahar tends to bury, uproot and otherwise kill trees, said Bryan Black, a tree ring scientist at the Laboratory of Tree-Ring Research at the University of Arizona.

This Publishing continues to Part [ 2 ]. The World Students Society thanks Katherine Kornei.