UTC time | 1902-08-22 03:00:22 |
---|---|
ISC event | 16957769 |
Local date | August 22, 1902 |
Local time | 09:00:22 |
Magnitude | 7.7 Mw |
Depth | 18.0 km (11.2 mi) |
Epicenter | 39°52′N76°25′E / 39.87°N 76.42°E |
Type | Thrust |
Areas affected | China & Kyrgyzstan |
Max. intensity | RFS X (Extremely high intensity tremor) |
Aftershocks | Many. Largest was a Ms 6.8–7.3 |
Casualties | 5,650–10,000 dead |
The 1902 Turkestan earthquake (also known as the Artush or Kashgar earthquake) devastated Xinjiang, China, near the Kyrgyzstan border. It occurred on August 22, 1902, at 03:00:22 (09:00:22 local time) with an epicenter in the Tien Shan mountains. [1] The thrust earthquake measured 7.7 on the moment magnitude scale (Mw ) and had a depth of 18 km (11 mi).
The Tien Shan mountains is situated in a zone of complex convergence caused by the Indian–Eurasian plate interaction. This zone is actively deforming—accommodated by active thrust faults responsible for seismic activity. The mainshock was preceded by an intense series of foreshocks in the years prior. Many aftershocks followed, several were larger than magnitude 6.0 and the largest measured 6.8–7.3. Aftershocks were recorded for three years. Additional shocks were recorded over a decade after the mainshock.
An estimated 5,650–10,000 people were killed in the mainshock. Widespread destruction occurred—at least 30,000 homes were destroyed. Shaking was felt across an area of 927,000 km2 (358,000 sq mi). The effects of the earthquake led government officials to relieve victims of taxes and provide compensation.
The Pamir–Tien Shan region is situated in a broad deformation zone caused by the ongoing collision of the Indian plate with the Eurasian plate. This deformation led to the formation of the Tien Shan mountains. [2] Its formation began in two stages during the Paleozoic era—first (southern Tien Shan) in the Late Devonian–early Carboniferous and later (northern Tien Shan) in the late Carboniferous–early Permian. [3] Before the Indian subcontinent collided with Eurasia, there were island arcs and microcontinents (terranes) between the two landmasses. These terranes were later accreted to Eurasia as the northward-moving Indian subcontinent collided, and are now in present-day Central Asia. The collision of terranes and island arcs as well as the collision with Eurasia eventually formed the Tien Shan mountains. Ancient suture zones mark the boundary where these collisions took place. [3] [4] The region is dominated by large, north and south dipping thrust faults along the southern edge of the Tien Shan mountains, and the northern boundary of the Tarim Basin. [2] The Tien Shan actively accommodates crustal shortening by underthrusting of the Tarim Basin in the south and overthrusting of the Pamirs in the west southwest. Most of the 20 ± 2 mm (0.787 ± 0.079 in)/year shortening is accommodated along its southern boundary. The northwestern Tien Shan is seismically active—earthquakes are caused by thrust faulting and usually have shallow focal depths of 15 km (9.3 mi) or less. [5]
The mainshock was recorded on seismographs across Europe. [6] It was also instrumentally recorded in Cape Town, Toronto, Irkutsk, and Christchurch. [7] It is the largest and earliest instrumentally recorded earthquake in the Tien Shan region. [8] Previously thought to have a seismic magnitude exceeded 8, [5] [9] such as in Chinese earthquake catalogs which placed the surface-wave magnitude (Ms ) at 8.25 (written as 81⁄4). [10] Seismologists Beno Gutenberg and Charles Francis Richter assigned mb (body wave magnitude) 7.9 and Ms 8.6, respectively. [11] Due to the sparse network of seismic instruments to record the mainshock, its magnitude was greatly overestimated. [12] In 2017, the magnitude was recalculated to Mw 7.7 ± 0.3 and Ms 7.8 ± 0.4, at a focal depth of 18 km (11 mi). The epicenter was also relocated ( 39°52′N76°25′E / 39.87°N 76.42°E ) further east from previous determinations ( 40°00′N77°00′E / 40.0°N 77.00°E ). [5]
Scientific knowledge of the earthquake was limited due to the period when it happened. Academic research into the event spanned nearly 40 years, but due to the inaccessible location, understanding its characteristics was a challenge. Strike-slip and thrust faulting was previously suggested as the mechanism of this earthquake. The lack of an agreement on its source is due to the complex tectonic setting. [13]
The Ttiotegongbaizi–Aerpaleike Fault (TAF) located at the southern flanks of the Tien Shan range, [14] near the western part of the larger Kalpin fold and thrust belt, was postulated as the source fault. [5] [15] This thrust fault is 200 km (120 mi) long, and has a gentle wave-shaped surface fault trace. It dips to the north at varying angles of 25° to 60°. For a magnitude 7.7 earthquake, a 110 km (68 mi) rupture is needed, and the dimensions of the TAF suggest it is large enough to be the source. The fault is within area with the highest seismic intensity based on observations. Thrust faulting was also indicated by the earthquake's focal mechanism, further supporting the theory. Field observations along the TAF found no trace of surface ruptures indicating the event was a blind thrust earthquake. [5] The same fault system was responsible for a Ms 6.9 earthquake in 1996. [16] [17]
Also proposed was a steep-dipping left-lateral strike-slip boundary fault inferred to be the source. The proposed fault marks the boundary between the southwestern Tien Shan and northern Tarim Basin. However, no surface deformation supports the existence of strike-slip deformation in the area. Moreover, reflection seismology does not support the existence of fault with such a characteristic in the area. [13]
Scientists also proposed that the earthquake was the result of two thrust faults rupturing in succession of each other. Two sub-parallel surface ruptures trending north–northeast were identified and attributed to the earthquake. These surface ruptures were identified via field studies, digital elevation model data and remote sensing, which had a combined length of 108 km (67 mi). They were located along pre-mapped faults—namely the Autushi and Keketamu faults with lengths of 60 km (37 mi) and 48 km (30 mi), respectively. These faults located at the base of the Tien Shan and are exposed at the base of anticlines. These south-dipping faults displayed recent thrust faulting activity and thrust-related folds. A possible maximum vertical displacement of 2.9 ± 0.1 m (9 ft 6.2 in ± 3.9 in), and an average of 2.5 m (8 ft 2 in) was measured. [13]
The earthquake was felt strongly across Central Asia for 927,000 km2 (358,000 sq mi), extending from south of Tashkent to north of Almaty. In Xinjiang, it was felt in Yining, Ürümqi, Korla, Taxkorgan and Hotan. It had a maximum intensity of X on the Modified Mercalli, Rossi–Forel, and Medvedev–Sponheuer–Karnik scales. [10] [18] Isoseismal X was felt over an elliptical area for 7,500 km2 (2,900 sq mi), in which the cities of Artux, Songtak, Halajun, and Ahu were within. Shaking occurred in an east–west direction at the southern base of the Tien Shan. [5] Isoseismal IX covered 18,200 km2 (7,000 sq mi), extending east–west from Wuqia to Karaqi. It was felt as far south in Kashgar, Shule, Shufu and Jiashi. Isoseismal VIII was felt in Kangsu, Toyun, Uqturpan, and Akto. It was also felt strongly in the counties of Yopurga, Kalpin, Yengisar and Maralbexi. [12] [19] [20]
Seismicity in the area prior to the mainshock had been relatively high. Multiple earthquakes of ~Ms 6.0 occurred, however, a large 650 km (400 mi) seismic gap existed. Historical records of earthquakes date back up to 10 years before 1902. In 1892, an Ms 6.3 event struck southeast of the 1902 mainshock. After a Ms 7.5 earthquake struck Tashkorgan in 1895, seismicity progressed north towards Atushi. The city was affected by a destructive earthquake (Ms 6.0+) once every year from 1896 to 1898. This high rate of seismicity ceased from 1899 and leading to the mainshock. Between 10 and 20 days before the mainshock, an estimated magnitude 3.1 tremor was recorded at Upal. [21] [19] [12] [20] [22]
Severe aftershocks were felt every day up till August 30. [6] There were at least 16 aftershocks with a recorded magnitude of 4.7 or greater from 1902 to 1926—eight were recorded within a month after the mainshock. The first recorded aftershock measuring Ms 6.1 occurred at 23:00 on August 22. Several aftershocks registered magnitude 6.0 or greater in the following years. [10] A Ms 6.8 or 7.3 aftershock occurred on August 30 with an epicenter 70 km (43 mi) from that of the mainshock. [23] By December 19, eight aftershocks were recorded with Ms between 5.7 and 6.4. There were few aftershocks recorded in 1905—possibly because earthquakes during this period went unrecorded. Strong earthquakes continued to rock the mainshock area for years—a Ms 5.8 in 1916, Ms 6.5 in 1919, and two Ms 5.0+ in 1920. The Tien Shan mountains was also the site of earthquakes in December 1906 and January 1911. [12] [19] [20]
There were unusual noises, peculiar animal behaviors, lights and a change in the weather prior to the mainshock. In Ahu, two hours before the earthquake, cattle, horses, chickens, dogs, cats and other livestock made unusual sounds. In areas which would eventually experience intense (VIII–IX) shaking, animals ran, flew or barked. Loud sounds emitted from the ground and was heard in Maralbexi. The sounds were described as similar to thunder, an airplane or gun blasts. In Artux, it was heard from the west, while at Shule, it was heard from the north. Lights were observed at Jiashi, Shufu, Artux and other places within the meizoseismal area. At Jiashi, these were described as "fire" and "lightning". At Shufu, a meteor-like fireball was observed. The weather was also unusually windy and rainy—there was also hail shortly before the mainshock struck. [19] [12] [20]
The earthquake produced strong shaking for 1.5 minutes. [6] Between 5,650 and 10,000 people were killed [24] and more than 30,000 homes collapsed. [25] An additional 600 livestock including sheep, cattle, camels, and donkeys died. [25] In Ahu, all houses with the exception of one located on bedrock collapsed. More than 300 were killed in the township—about 20 percent of its population. The earthquake triggered massive landslides with an estimated volume exceeding 200,000 m3 (7,100,000 cu ft). [26] [19] [12]
In the meizoseismal area, trees swayed in a forceful manner such that their tips touched the ground. Some trees were uprooted or snapped. Many tents were affected. Ground slumping near a riverbank blocked roads and dammed streams. Water gushed out from many of the large fissures. The largest fissure measured 1 km (0.62 mi) long, several meters wide, and 3 m (9.8 ft) deep. Five hundred people died in the area. Many domesticated animals were also killed. Old springs dried up while new ones formed. [27]
In Kashgar, sun-dried brick walls and homes collapsed. Masonry buildings did not sustain serious damage. [6] Numerous fissures opened in the northern entrance of the city, where the city walls had toppled. Several historical monuments including the Xiangfei Tomb partially collapsed and fractured. [27] At least 667 people died and thousands more were injured in Kashgar. [6] [28] In Artux, north of Kashgar, the earthquake collapsed nearly every home. Between 5,000 and 6,000 were killed in Artux. The Artux Grand Mosque, the first of its kind in Xinjiang, toppled. Up to half its city walls fell. At least 400 people perished in the village of Astyn, while in Jangi, 20 were killed. [29] In Yarkand, damage was lighter but two children died from toppled walls. Damage was reported in Naryn and At-Bashy but there were no fatalities. [6]
Valleys collapsed and many river channels were blocked, creating waterfalls and new springs. Most earth-constructed homes were destroyed in Songtak, and more than 50 people were killed. At Üstün Atux, 90 percent of its housing stock were destroyed. Several people died in Halajun. Forty deaths were recorded in Upal and the township lost 20 percent of its homes. A death toll exceeding 30 was recorded at Baykurut. [19]
Some villages spent four days burying dead bodies in the wake of the disaster. The Qing dynasty government provided pensions and tax exemptions for the victims. Recorded in Volume 566 of the Qing Shilu (Veritable Records of Qing), the Governor of Gansu and Xinjiang, Rao Yingqi, ordered an investigative committee to evaluate the situation and provide compensation. Guangxu Emperor also issued an edict for tax exemptions. [30]
The 1920 Haiyuan earthquake occurred on December 16 in Haiyuan County, Ningxia Province, Republic of China at 19:05:53. It was also called the 1920 Gansu earthquake because Ningxia was a part of Gansu Province when the earthquake occurred. It caused destruction in the Lijunbu-Haiyuan-Ganyanchi area and was assigned the maximum intensity on the Mercalli intensity scale. About 258,707-273,407 died, making it one of the deadliest earthquakes in China and disasters in China by death toll.
The 2003 Bachu earthquake occurred on 24 February at 10:03 local time in the Xinjiang Autonomous Region in northwest China. The epicentre was located near to the town of Jiashi and Bachu County, approximately 105 km east of Kashgar and 310 km west of Aksu.
The 2002 Denali earthquake occurred at 22:12:41 UTC November 3 with an epicenter 66 km ESE of Denali National Park, Alaska, United States. This 7.9 Mw earthquake was the largest recorded in the United States in 37 years. The shock was the strongest ever recorded in the interior of Alaska. Due to the remote location, there were no fatalities and only one injury.
The 1986 Chalfant Valley earthquake struck southern Mono County near Bishop and Chalfant, California at 07:42:28 Pacific Daylight Time on July 21. With a moment magnitude of 6.2 and a maximum Mercalli intensity of VI (Strong), the shock injured two people and caused property damage estimated at $2.7 million in the affected areas. There was a significant foreshock and aftershock sequence that included a few moderate events, and was the last in a series of three earthquakes that affected southern California and the northern Owens Valley in July 1986.
On 7 December 2015, an earthquake measuring 7.2 on the moment magnitude scale struck Tajikistan 105 km (65 mi) west of Murghab at 07:50 UTC at a depth of 26.0 km (16.2 mi). The earthquake was also felt in neighboring Xinjiang in China, India, Afghanistan, Pakistan and Kyrgyzstan.
The 2017 Jinghe earthquake occurred at 07:27 China Standard Time on 9 August 2017, in Jinghe County, Bortala Mongol Autonomous Prefecture, Xinjiang Uyghur Autonomous Region, China, with magnitude 6.6 and depth 11 kilometres. The epicentre was 44.27°N 82.89°E. Most cities in northern Xinjiang felt the quake. This earthquake occurred on the Tian Shan seismic zone. There was no direct relationship to the earthquake in Jiuzhaigou County that occurred the previous day.
The 1946 Sagaing earthquakes struck central Burma at 15:17 local time on 12 September. The first earthquake measured a magnitude of 7.3 Mw and was followed by a 7.7 Mw earthquake. Both events remain some of the largest in the country since the 1762 Arakan earthquake.
The Haiyuan Fault is a major active intracontinental strike-slip (sinistral) fault in Central Asia.
The 1988 Lancang–Gengma earthquakes, also known as the 11.6 earthquakes by the Chinese media were a pair of devastating seismic events that struck Lancang and Gengma counties, Yunnan, near the border with Shan State, Burma. The earthquake measured moment magnitude (Mw ) 7.0 and was followed 13 minutes later by a 6.9 Mw shock. These earthquakes were assigned a maximum China seismic intensity of IX and X, respectively. Between 748 and 939 people were killed; more than 7,700 were injured. Both earthquakes resulted in US$270 million in damage and economic losses. Moderately large aftershocks continued to rock the region, causing additional casualties and damage.
The 1973 Luhuo earthquake struck near the town of Zhaggo in Garzê Tibetan Autonomous Prefecture of Sichuan Province, China on February 6, 1973, with a magnitude of 7.6 Ms. The earthquake had a maximum intensity of X (Extreme) on the Modified Mercalli intensity scale. It resulted in between 2,175 and 2,204 deaths and a further 2,743 injuries. Serious and widespread destruction occurred in Luhuo County.
The 1906 Manasi earthquake (玛纳斯地震), also known as the Manas earthquake occurred in the morning of December 23, 1906, at 02:21 UTC+8:00 local time or December 22, 18:21 UTC. It measured 8.0–8.3 on the moment magnitude scale and 8.3 on the surface-wave magnitude scale. The epicenter of this earthquake is located in Manas County, Xinjiang, China. An estimated 280–300 people died and another 1,000 more were injured by the earthquake.
The 1994 Mascara earthquake occurred on August 18 at 02:13 local time with an epicenter in a rural part of Algeria. The earthquake measured 5.8 on the moment magnitude scale (Mw ) and had a depth of 10 km (6.2 mi). It caused the deaths of 171 people, left up to 12,500 homeless, and destroyed thousands of homes in Mascara Province. Many homes were damaged or destroyed due to poor building quality which collapsed on the inhabitants and resulted in a majority of the casualties. The national government launched a rapid response effort in its aftermath.
The Nemuro-Oki earthquake in scientific literature, occurred on June 17 at 12:55 local time. It struck with an epicenter just off the Nemuro Peninsula in northern Hokkaidō, Japan. It measured 7.8–7.9 on the moment magnitude scale (Mw ), 8.1 on the tsunami magnitude scale (Mt ) and 7.4 on the Japan Meteorological Agency magnitude scale (MJMA ).
The 2021 Maduo earthquake, also known as the 5.22 earthquake struck Madoi County in Qinghai Province, China on 22 May at 02:04 local time. The earthquake had a moment magnitude and surface-wave magnitude of 7.4. Highway bridges, roads and walls collapsed as a result of the earthquake. According to an anonymous source, at least 20 people were killed, 300 were injured, and 13 were missing. Officials stated that there were no deaths but 19 people sustained minor injuries. It was the strongest in China since 2008. It was assigned a maximum intensity of X in Machali, Maduo County on the China seismic intensity scale and Modified Mercalli intensity scale. This earthquake was preceded by another unrelated earthquake that occurred 5 hours earlier in Yunnan.
The 2020 Kashgar earthquake, also known as the Jiashi earthquake occurred on 19 January 2020 at 21:27:56 China Standard Time in Xinjiang Province, China. According to the United States Geological Survey, the earthquake had a moment magnitude of 6.0 and a surface wave magnitude of 6.4 according to the China Earthquake Network Center. It struck at a shallow depth of 5.6 km according to the USGS while the CENC has the figure at 16 km. Local emergency management agencies said the earthquake damaged more than 1,000 homes and businesses in the nearby populated towns and villages. One person is known to have died while two other children were injured.
The 1995 Menglian earthquake or 1995 Myanmar–China earthquake occurred on 12 July at 05:46:43 local time in the Myanmar–China border region. The earthquake had an epicenter on the Myanmar side of the border, located in the mountainous region of Shan State. It registered 7.3 on the Chinese surface wave magnitude scale (Ms ) and 6.8 on the moment magnitude scale (Mw ). With a maximum Mercalli intensity assigned at VIII, it killed 11 people and left another 136 injured. Over 100,000 homes in both countries were destroyed and 42,000 seriously damaged. Some damage to structures were also reported in Chiang Mai and Chiang Rai, Thailand. The low death toll from this earthquake was attributed to an early warning issued prior to it happening. Precursor events including foreshocks and some seismic anomalies led to an evacuation of the area before the mainshock struck. It is thought to be one of the few successfully predicted earthquakes in history.
The 1979 Ghaenat earthquakes were a series of large earthquakes in Qaen County, Khorasan Province, northeast Iran, near the Afghanistan border. The first mainshock, known as the Korizan earthquake with a surface wave magnitude (Ms ) of 6.6 and moment magnitude (Mw ) of 6.8, struck on November 14, while the Ms 7.1 or Mw 7.2 Koli-Boniabad earthquake struck on November 27. The two mainshocks were assigned a maximum Modified Mercalli intensity of VIII (Severe) and X (Extreme), respectively. The earthquakes caused extensive damage throughout northeastern Iran, killing an estimated 297 to 440 people and left at least 279 injured.
The 1889 Chilik earthquake occurred on July 11 on the Gregorian calendar, or June 30 on the Julian calendar at 15:14 local time in the Tien Shan mountains. The earthquake measured an estimated Mw 7.9–8.0 on the moment magnitude scale and was assigned a maximum intensity of X (Devastating) on the MSK 64 and Rossi-Forel scales. Over 92 people across Kazakhstan, Kyrgyzstan and China were killed.
The Shōnai offshore earthquake occurred at around 14:00 on December 7, 1833. It struck with an epicenter in the Sea of Japan, off the coast of Yamagata Prefecture, Japan. A tsunami was triggered by the estimated MJMA 7.5–7.7 earthquake. One hundred and fifty people were killed and there was severe damage in the prefecture.
The 1979 Saint Elias earthquake affected Alaska at 12:27 AKST on 28 February. The thrust-faulting Mw 7.5 earthquake had an epicenter in the Granite Mountains. Though the maximum recorded Modified Mercalli intensity was VII, damage was minimal and there were no casualties due to the remoteness of the faulting. Damage also extended across the border in parts of Yukon, Canada.
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