TEOTWAWKI?
No, says the USGS, in 1999, what will we see in the "real millennium"?
1999's Disasters - Far
From History's Worst
Says USGS
www.unisci.com
1-4-2000
Nature dealt staggering blows to the Earth and its people in 1999: Killer landslides in Venezuela and Mexico; devastating earthquakes in Turkey and Taiwan; massive floods along the East Coast of the United States. But these were not the worst disasters of the century, either in the power of the events or in the loss of life and property they caused.
"The costs of natural disasters -- lives lost, homes destroyed, economies disrupted -- have skyrocketed in this century, as the world's population has grown and has moved onto areas that are vulnerable to earthquakes, hurricanes, landslides, and other natural hazards," said USGS Director Chip Groat. "But there is reason for hope. By understanding how and where these natural events occur, so that we can build and live safely on the Earth, and by providing real-time information about floods, earthquakes, and other hazards, so that we can respond effectively when disaster strikes, the USGS is helping build stronger, safer communities that are resilient to natural disaster."
Landslides
Landslides -- lethal mixtures of water, rocks, and mud -- generally are triggered by earthquakes, volcanoes, or weather events. The two largest landslides in the world this century occurred at Mount St. Helens, Washington, in 1980 and at Usoy, Tajikistan, in 1911.
At Mount St. Helens, a moderate earthquake caused roughly 1.7 cubic miles of rocks and mud to break free and slide down the side of the volcano, releasing pent-up pressure to produce the major eruption of May 18.
Although this was the largest landslide recorded in historic time, fewer than 60 people were killed because most residents and visitors had been evacuated. The Usoy landslide, also triggered by an earthquake, moved 1.5 cubic miles of material and built a dam 1880 feet high (half again as high as the Empire State Building) on the Murgob River; the dam still impounds a lake nearly 40 miles long. This landslide took place in a sparsely populated area and thus caused few deaths.
An earthquake was responsible for the deadliest landslide this century, which caused 40,000-50,000 deaths in western Iran on June 20, 1990. A magnitude 7.8 earthquake at Mount Huascaran, Peru, on May 21, 1970, triggered a rock and snow avalanche that buried the towns of Yungay and Ranrahirca, killing perhaps as many as 20,000 people.
Weather-related landslides also proved deadly in recent years. The death toll is still unclear from the rain-caused landslides that hit Venezuela in mid-December of 1999; official estimates are as high as 30,000 deaths. On October 30, 1998, the day of peak rainfall as Hurricane Mitch moved across Central America, the side of Casita Volcano collapsed, creating a landslide/mudflow that wiped out two towns in Nicaragua and killed more than 2,000 people.
The most costly landslide in U.S. history was a relatively slow-moving event in Thistle, Utah, in the spring of 1983. The landslide, caused by the wet El Nião winter of 1982-83, dammed the Spanish Fork River and buried U.S. Highway 6 and the main line of the Denver and Rio Grande Western Railroad. The town of Thistle was inundated under the floodwaters rising behind the landslide dam. Total losses were estimated at more than $400 million in 1983 dollars.
Earthquakes
The largest earthquake this century was a magnitude 9.5 event that struck Chile on May 22, 1960. More than 2,000 people were killed in Chile, Hawaii, Japan, and the Philippines from this earthquake and the deadly tsunami that the earthquake created. (cont)
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