Earthquake Damage and Intensity Devastation Effects Encountered Historically

Earthquake Damage and Intensity Devastation Effects Encountered Historically

0 No detectable or measurable earthquake effect although about 100,000 quakes a year can be felt and at least 1000 cause some damage

1 Very slight earthquake effects felt by sensitive persons who may experience dizziness or nausea; other creatures may appear disturbed; gentle swaying may affect bodies of water as well as buildings and trees

2 Slight earthquake effects sensed by sensitive persons as well as other creatures who display uneasiness; hanging lamps and pictures swing slightly; buildings and trees sway slightly

3 Very moderate earthquake effects sensed by a few persons as well as by the most nervous and the most sensitive; dishes on shelves may rattle as may many windows; canned goods stored on shelves may rattle and may fall off, parked vehicles may rock and this is true of shrubs and trees

4 Moderate earthquake sensed by many and sufficient to awaken light sleepers; house frames creak and houses sway slightly; shrubs and trees tremble; parked vehicles may rock and sway

5 Near medium-strength earthquake felt by everyone and frightening most persons who tend to leave buildings and run out of doors to avoid cracking ceilings and crumbling walls; in older buildings plaster falls, ceilings crack, and windows break; pictures may fall off their hangers, dishes and glasses tumble off shelves; heavy desks and tables move and many may topple; old and weak chimneys may crack off at the roofline; ornamental cornices fall from buildings; church bells toll by themselves

6 Full-strength earthquake causing general fright approaching panic; stone walls crack; steep slopes and riverbanks crack; chimneys and towers may crack apart and fall; trees shake violently and often fall as do limbs; the Los Angeles Earthquake of 1971 measured 6.6, caused considerable damage, and took the lives of some 65 people

7 More devastating and more severe type of earthquake such as occurred in Nicaragua and Guatemala where thousands were killed in 1972 and 1976, respectively; or in the Chile Quake of 1906, which preceded the San Francisco Earthquake and Fire by only two days; 20,000 lives were lost in Valparaiso and 503 in San Francisco; both seismic disturbances were calculated in later years as representing 7.8 on the Richter Scale, though this figure has since been revised upward to greater than 8

8 Still more devastating and more severe earthquake causing general panic and marked by widespread land and water disturbances; many dams and dikes break, discharging vast volumes of flooding water; underground cables and pipelines crack and tear apart; railway rails bend and twist; brick, glass, and masonry facades peel off buildings and fall to the ground endangering people; loss of life can be quite severe as in the Peruvian Quake of 1970, accounting for the loss of some 66,000 people, or the Alaska Quake of 1964, reported as 8.4 on the scale, and marked by heavy damage in downtown Anchorage where 131 lost their lives; earthquakes of even greater magnitude occurred in Lisbon, Portugal in 1755 when 60,000 lives were lost and lakes in far off Norway were disturbed violently; the Shensi Province Quake, occurring in China in 1566, cost some 830,000 lives, calculated to have been 8.9 on the Richter Scale as was Japan’s great quake of 1923, destroying all of Yokohama and half of Tokyo, and killing 143,000 people; the sea bottom in Sagami Bay sank 387 meters or 1300 feet; earthquakes of this magnitude afflicted New Madrid, Missouri in 1811, Charleston, South Carolina in 1886, and are predicted as long overdue along the San Andreas Fault Zone of California extending from south of the Mexican Border to San Francisco and northward; overall damage might well equal or exceed the Shinsai or Great Quake felt around Tokyo in 1923; a Chinese earthquake of July 26, 1976 registered

Earthquake Data

8.2 with a 7.9 aftershock the following day; shocks affected an area in and around Peking and Tientsin and killed some 750,000 people

9 Most devastating and most intense earthquakes top of the Richter Scale, extending from 0 to 9; minor earthquakes and tremors provide stress-relief cracking of and easing of the great tectonic energy tension beneath us

Krakatoa volcanic Indonesian island between Java and Sumatra, scene in August 1883 of one of the world’s worst earthquakes

Recent Earthquakes Philippines (1991); Armenia (1989); Chile (1985); Colombia-Ecuador (1979); India (1988); Iran (1990); Japan (1931, 1946, 1948, 1983, 1993, 1995); Mexico (1985, 1999); San Francisco (1906, 1990), Los Angeles (1994), western Turkey (1999)

Greatest Earthquake ? Measuring 9.5 on the Richter Scale, an earthquake in southern Chile killed an estimated 5,700 people in May 1960

Emoticons