from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A landslide or mudflow of volcanic fragments on the flanks of a volcano.
- n. The deposit produced by such a landslide.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A volcanic mudflow.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. an avalanche of volcanic water and mud down the slopes of a volcano
In extreme scenarios, a flood becomes a massive debris flow known as a lahar-a deadly tsunami of mud, boulders, and uprooted trees that can gouge 100-foot-deep gullies, flatten forests, and jump longstanding banks.
Active river channels and those perennially identified as lahar prone in the southern sector should also be avoided especially during bad weather conditions or when there is heavy and prolonged rainfall.
This combined with the tons of volcanic ash and debris that had collected on Mayon's slopes, creating a fast-moving avalanche of mud and boulders called lahar, destroying villages and leaving 1,266 people dead.
A lahar is a sudden and usually eruption induced mud flow made up of ash and water - very destructive and dangerous.
The noon was grey and still as we left the Whydah of the south, but at 2 P.M. the sea-breeze came up stiff and sudden, the tide also began to flow; the river roared; the meeting of wind and water produced what the Indus boatmen call a "lahar" (tide rip), and the Thalweg became almost as rough as the Yellala.
Mount Rainier in Washington erupted as recently as 5,700 years ago, unleashing a lahar, or mud flow, that reached all the way to what are now the suburbs of Seattle.
In some portions on the lowland plains many residents remember massive mud and lahar flows that burried towns and villages in pryoclastic debris some three years ago.
Any sign of sustain rainfall is a signal for people to go to evacuation areas as the steep mountain slopes can create massive flash floods of lahar and volcanic mudflows which can rage down slopes carrying with them boulders and the wet cement like 'Lahar flows' that can destroy almost any structure in the path of the fast flowing debris.
Directives all seem to focused on the most pressing problem and indeed one of the worst natural disasters of recent memory exceeded only by the 1990 Mt. Pinatubo disaster and subsequent year's lahar related problems that plagued the country in up to 1993.
We'd be far better off spending tax dollars starting tomorrow building earthquake bunkers or meteor hit bunkers, or lahar bunkers for Mt. Rainier eruptions, as any of those events could easily occur in the next 100 years and would a far more disastrous consequence than a 1 foot rise in sea level.