Further Reading

Albritton, C. C., Jr. Catastrophic Episodes in Earth History. London: Chapman and Hale, 1989. Alvarez, Walter. T. Rex and the Crater of Doom. Princeton, N.J.: Princeton University Press, 1997. Blong, Russel J. Volcanic Hazards: A Sourcebook on the Effects of Eruptions. New York: Academic Press, 1984.

Eldredge, N. Fossils: The Evolution and Extinction of Species. Princeton, N.J.: Princeton University Press, 1997. Fisher, R. V., G. Heiken, and J. B. Hulen. Volcanoes: Crucibles of Change. Princeton, N.J.: Princeton University Press, 1998.

Francis, Peter. Volcanoes: A Planetary Perspective. Oxford:

Oxford University Press, 1993. Martin, P. S., and R. G. Klein, eds. Quaternary Extinctions. Tucson: University of Arizona Press, 1989. Melosh, H. Jay. Impact Cratering: A Geologic Process.

Oxford: Oxford University Press, 1988. Robock, Alan, and Clive Oppenheimer, eds. Volcanism and the Earth's Atmosphere. Washington D.C.: American Geophysical Union, 2003. Scarth, Alwyn. Vulcan's Fury, Man against the Volcano.

New Haven, Conn.: Yale University Press, 1999. Sepkoski, J. J., Jr. Mass Extinctions in the Phanerozoic Oceans: A Review. In Patterns and Processes in the History of Life. Amsterdam: Springer-Verlag, 1982. Simkin, T., and R. S. Fiske. Krakatau 1883: The Volcanic Eruption and Its Effects. Washington, D.C.: Smithsonian Institution Press, 1993.

Freeman, 1986. Stanley, Steven M. Extinction. New York: Scientific American Library, 1987.

mass wasting Mass wasting is the movement of soil, rock, and other Earth materials (together called regolith) downslope by gravity without the direct aid of a transporting medium such as ice, water, or wind. An estimated 2 million or more mass movements occur each year in the United States alone. Mass movements occur at various rates, from a few inches (few centimeters) per year to sudden catastrophic rock falls and avalanches that can bury entire towns under tons of rock and debris. In general, the faster the mass movement, the more hazardous it is to humans, although even slow movements of soil down hill slopes can be extremely destructive to buildings, pipelines, and other construction and infrastructure. In the United States alone, mass movements kill tens of people and cost more than 1.5 billion dollars a year. Other mass movement events overseas have killed tens to hundreds of thousands of people in a matter of seconds. Mass wasting occurs under a wide variety of environmental conditions and forms a continuum with weathering, as periods of intense rain reduce friction between regolith and bedrock, making movement easier. Mass movements also occur underwater, such as the giant submarine landslides associated with the 1964 Alaskan earthquake.

Mass movements are a serious concern and problem in hilly or mountainous terrain, especially for buildings, roadways, and other features engineered into hillsides, in addition to along riverbanks and in places with large submarine escarpments, such as along deltas (like the Mississippi Delta in Louisiana). Seismic shaking and severe storm-related flooding further compound the problem in some prone areas.

Imagine building a million-dollar mansion on a scenic hillside, only to find it tilting and sliding down the hill at a few inches (5-10 centimeters) per year. Less spectacular but common effects of slow downhill mass movements are the slow tilting of telephone poles along hillsides and the slumping of soil from oversteepened embankments onto roadways during storms.

Mass wasting is becoming more of a problem as the population moves from the overpopulated flat land to new developments in hilly terrain. In the past, small landslides in the mountains, hills, and canyons were not a serious threat to people, but now large numbers of people live in landslide-prone areas, thus landslide hazards and damage are rapidly increasing.

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The Basic Survival Guide

The Basic Survival Guide

Disasters: Why No ones Really 100 Safe. This is common knowledgethat disaster is everywhere. Its in the streets, its inside your campuses, and it can even be found inside your home. The question is not whether we are safe because no one is really THAT secure anymore but whether we can do something to lessen the odds of ever becoming a victim.

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