The 1981 Dawu earthquake occurred on ,
[ in ]Sichuan
Sichuan is a province in Southwestern China, occupying the Sichuan Basin and Tibetan Plateau—between the Jinsha River to the west, the Daba Mountains to the north, and the Yunnan–Guizhou Plateau to the south. Its capital city is Cheng ...
, China. Registering a surface-wave magnitude
The surface wave magnitude (M_s) scale is one of the magnitude scales used in seismology to describe the size of an earthquake. It is based on measurements of Rayleigh surface waves that travel along the uppermost layers of the Earth. This mag ...
of 6.8, the earthquake killed about 150 people and injured roughly 300 more. It caused comprehensive damage within close range of its epicenter.
Background
China has an extensive history of catastrophic earthquakes that ranges back to 1290. The first verified earthquake took place in Chih-li
Zhili, alternately romanized as Chihli, was a northern administrative region of China since the 14th century that lasted through the Ming dynasty and Qing dynasty until 1911, when the region was dissolved, converted to a province, and renamed ...
, killing roughly 100,000 people. The next great earthquake was probably the 1556 Shaanxi earthquake
The 1556 Shaanxi earthquake ( Postal romanization: ''Shensi''), known in Chinese colloquially by its regnal year as the Jiajing Great Earthquake "" ('' Jiājìng Dàdìzhèn'') or officially by its epicenter as the Hua County Earthquake "" ('' ...
, the most devastating earthquake of all time. Roughly 830,000 were killed by the event. Other earthquakes in 1917, 1918, 1920, 1923, 1925, 1927, 1931, 1932, 1933, 1948, 1950, 1966, 1969, 1970, 1974, 1975, 1976 each killed at least one thousand people. Since 1981, earthquake fatalities have diminished greatly, though have not been stopped. As recently as 2008, an earthquake in Sichuan killed nearly 90,000 people.
Characteristics
The epicenter was pinpointed to Dawu County in Sichuan. Its official magnitude was 6.8 and its surface wave magnitude reached 6.6.focal mechanism
The focal mechanism of an earthquake describes the Fault (geology)#Slip.2C heave.2C throw, deformation in the Hypocenter, source region that generates the seismic waves. In the case of a Fault (geology), fault-related event, it refers to the ori ...
indicates that the earthquake was probably a result of left lateral strike-slip faulting
In geology, a fault is a Fracture (geology), planar fracture or discontinuity in a volume of Rock (geology), rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust (geology ...
[ on the Daofu fault. The Daofu fault forms part of the ]Xianshuihe fault system
The Xianshuihe fault system or the Yushu-Ganzi-Xianshuihe fault system is a major active sinistral (left-lateral) Fault (geology)#Strike-slip faults, strike-slip fault zone in southwestern China, at the eastern edge of the Tibetan Plateau. It has ...
, which experienced a sequence of four earthquakes greater than 6.0 between 1973 and 1982, with each event triggering the next in the sequence by changing the stress state.surface rupture
In seismology, surface rupture (or ground rupture, or ground displacement) is the visible offset of the ground surface when an earthquake rupture along a Fault (geology), fault affects the Earth's surface. Surface rupture is opposed by buried rup ...
has been reported for the 1981 earthquake.
Damage and casualties
The earthquake killed roughly 150 people and 300 or so were injured. Damage was considerable, but limited to a small zone around the area.[
]
References
External links
*
{{Earthquakes in China
Dawu Earthquake, 1981
Dawu Earthquake, 1981
Earthquakes in Sichuan