Landslides
Causing $1-2 billion in damages and more than 25 deaths per year, landslides are a major geologic hazard, caused by earthquakes and floods. Although, landslides are generally not as exciting or costly as earthquakes, major floods, tropical storms, and other natural disasters, they occur in more expanded places and may cause more property damage than any other geologic hazards. A wide variety of ground movements, such as rock falls, slope failure, and shallow debris flows can classify landslides. When a portion of a hill slope cannot support its own weight a landslide will occur. When rainfall or some other water source increases the water content of the slope the weakness is irritated, reducing the strength of the materials. Although gravity acting upon an increased slope is the main reason for a landslide, there are other elements that contribute to its cause. Loud sounds that occur during an earthquake also cause landslides. Erosion caused by rivers, glaciers, or ocean waves create oversteepened slopes. Heavy rains and melting snow weaken rock and soil slopes. Furth
This page updated: 16 November 1998 It is possible that any area made up of brittle and cracked materials lying on a steep slope will be subject to landslides. Scientists continue to try their best to lower the risk of landslides everywhere by producing landslide susceptibility maps for areas in the United States. Areas that are generally accessible to landslide hazards include: old landslides, bases of slopes, at the base of minor drainage hollows, at the base or top of an old fill slope or steep cut slope, and developed hillsides where leach field septic systems are used. However, there are areas that are safe from landslide activity: on hard bedrock that has not moved in the past, on flat land away from rapid changes in slope angle, and at the top or along the nose of ridges, set back from the tops of slopes. The URL of this page is http://landslides.usgs.gov/html_files/nlic/new1ft.shtml Even though, the natural cause of most landslides is unable to be stopped, geologic investigations, good engineering practices and effective enforcement of land-use management regula
Some common words found in the essay are:
, Giant Landslides, Hawaiian Islands, Gowen Groome, Alaska Hawaii, Page URL, Updated November, giant landslides, hawaiian islands, geologic hazards, cause landslides, landslide occur,
Approximate Word count = 735
Approximate Pages = 3 (250 words per page double spaced)
|
