The 1985 Kayrakkum earthquake (Russian: ) struck Soviet Tajikistan on October 13 at about 22:00 local time. The earthquake measured 5.8 and struck at a depth of . At least 29 people died, over 80 were injured and another 8,000 were made homeless. Damage totaled $US200 million. Figures of the casualties were not disclosed until the following month.

Tectonic setting

Central Asia Central Asia, also known as Middle Asia, is a subregion, region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes t ...

is situated in a region of active convergence involving the

Eurasian Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago ...

and

Indian Indian or Indians may refer to: Peoples South Asia * Indian people, people of Indian nationality, or people who have an Indian ancestor ** Non-resident Indian, a citizen of India who has temporarily emigrated to another country * South Asia ...

plates. While situated at a considerable distance from the

collision In physics, a collision is any event in which two or more bodies exert forces on each other in a relatively short time. Although the most common use of the word ''collision'' refers to incidents in which two or more objects collide with great fo ...

front, the Pamirs and Tien Shan have risen significantly due to

intraplate deformation Intraplate deformation is the folding, breaking, or flow of the Earth's crust within plates instead of at their margins. This process usually occurs in areas with especially weak crust and upper mantle, such as the Tibetan Plateau (Figure 1). Intr ...

brought by the collision. The earthquake occurred in the east–west trending

Fergana Valley The Fergana Valley (; ; ) in Central Asia lies mainly in eastern Uzbekistan, but also extends into southern Kyrgyzstan and northern Tajikistan. Divided into three republics of the former Soviet Union, the valley is ethnically diverse and in the ...

, situated between the

Pamirs The Pamir Mountains are a mountain range between Central Asia and Pakistan. It is located at a junction with other notable mountains, namely the Tian Shan, Karakoram, Kunlun, Hindu Kush and the Himalaya mountain ranges. They are among the world' ...

and

Tian Shan The Tian Shan,, , otk, 𐰴𐰣 𐱅𐰭𐰼𐰃, , tr, Tanrı Dağı, mn, Тэнгэр уул, , ug, تەڭرىتاغ, , , kk, Тәңіртауы / Алатау, , , ky, Теңир-Тоо / Ала-Тоо, , , uz, Tyan-Shan / Tangritog‘ ...

. The valley is seismically active—four earthquakes have magnitudes exceeding 7.0 since 1900. These earthquakes display thrust-faulting mechanism. One of the strongest earthquakes in the valley occurred in 1946, measuring 7.3.

Earthquake

The mainshock had a

focal mechanism The focal mechanism of an earthquake describes the deformation in the source region that generates the seismic waves. In the case of a fault-related event it refers to the orientation of the fault plane that slipped and the slip vector and is ...

corresponding to shallow reverse faulting with some strike-slip component.

Impact

In Kairakkum, 90 percent of the city's multi-story brick buildings were destroyed—this earned the earthquake a maximum

Modified Mercalli intensity The Modified Mercalli intensity scale (MM, MMI, or MCS), developed from Giuseppe Mercalli's Mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the eff ...

(MMI) of IX (''Violent''). The

Kayrakkum Reservoir Kayrakkum Reservoir ( Tajik: Обанбори Қайроққум; Russian: Кайраккумское водохранилище), also spelled variously as Qayroqqum, Qayraqqum, Kayrakum or Kairakum, is a large artificial lake in Ghafurov Distric ...

embankments failed and were pushed into the water. The collapse of a

carpet A carpet is a textile floor covering typically consisting of an upper layer of pile attached to a backing. The pile was traditionally made from wool, but since the 20th century synthetic fibers such as polypropylene, nylon, or polyester hav ...

factory caused many casualties during the evening shift. Many workers were trapped under the rubble. The earthquake razed many industrial buildings, homes and cultural infrastructures, according to state media

TASS The Russian News Agency TASS (russian: Информацио́нное аге́нтство Росси́и ТАСС, translit=Informatsionnoye agentstvo Rossii, or Information agency of Russia), abbreviated TASS (russian: ТАСС, label=none) ...

. At nearby villages, adobe houses collapsed. Several landslides swept away roads. South of Kayrakkum, at

Ghafurov tg, Ғафуров , image_skyline = , imagesize = , image_caption = , image_flag = , image_seal = , image_map = , map_caption = , pushpin_map = Tajikistan , pushpin_label_position =bottom , pushpin_mapsize = , pushpin_ ...

, a hospital was destroyed but its occupants had previously evacuated. Nearly 900 buildings were destroyed at

corresponding to MMI VIII (''Severe''). MMI VII damage was reported at Leninabad. Telephone services were cut at Leninabad. The city's carpet and silk manufacturing districts were heavily damaged. About away from Leninabad, a hydroelectric dam was slightly damaged. A

Soviet Communist Party "Hymn of the Bolshevik Party" , headquarters = 4 Staraya Square, Moscow , general_secretary = Vladimir Lenin (first)Mikhail Gorbachev (last) , founded = , banned = , founder = Vladimir Lenin , newspaper ...

official said that there was no conclusion to whether the damaged dam was at risk of collapsing or if there was a need to evacuate residents.

Aftermath

reported that it was the largest earthquake to strike the Soviet Union since 1976. Initial reports on October 15 stated that people had been killed and injured, but specific figures were not released. The

National Earthquake Information Center The National Earthquake Information Center (abbreviated NEIC) is part of the United States Geological Survey (USGS) located on the campus of the Colorado School of Mines in Golden, Colorado. The NEIC has three main missions: * First, the NEIC determ ...

in Colorado, United States described the earthquake as "moderate" in magnitude. Soviet leaders expressed their condolences to the victims. Local media reported that essential supplies were being distributed to the affected. Rescue workers at Leninabad attended to the ruins of the city's industrial area. ''

The Los Angeles Times ''The'' () is a grammatical article in English, denoting persons or things already mentioned, under discussion, implied or otherwise presumed familiar to listeners, readers, or speakers. It is the definite article in English. ''The'' is the m ...

'' said on November 7, Soviet newspaper '' Sotsialisticheskaya Industriya'' disclosed that the earthquake resulted in 29 fatalities and over 80 injuries. The figure was disclosed to stop "distortions and rumors" of the disaster. It is uncommon for Soviet media to release casualty numbers in disasters. An ''

Izvestia ''Izvestia'' ( rus, Известия, p=ɪzˈvʲesʲtʲɪjə, "The News") is a daily broadsheet newspaper in Russia. Founded in 1917, it was a newspaper of record in the Soviet Union until the Soviet Union's dissolution in 1991, and describes ...

'' reporter said that damage caused by the earthquake was "unnessary". He added that authorities have long "resisted" classifying the Leninabad oblast an earthquake-prone region. Buildings in the area had been constructed in such practice that was not ideal for surviving earthquakes. The Leninabad area also does not have any seismic instruments to monitor seismic activity to assist in

earthquake prediction Earthquake prediction is a branch of the science of seismology concerned with the specification of the time, location, and magnitude of future earthquakes within stated limits, and particularly "the determination of parameters for the ''next'' s ...

. A recent evaluation of seismic hazards found that the area can experience stronger earthquakes than previously thought, yet no action was taken by authorities. Existing structures were not strengthened, and there were no updated safety codes for newly constructed buildings. These factors led to considerable destruction.

References

External links