At 23:50 (

UTC+8 UTC+08:00 is an identifier for a time offset from UTC of +08:00. With an estimated population of 1.708 billion living within the time zone, roughly 24% of the world population, it is the most populous time zone in the world, as well as a ...

) on 6 February 2018, an earthquake of magnitude 6.4 on the

moment magnitude scale The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. It was defined in a 1979 pape ...

hit

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...

. The

epicenter The epicenter, epicentre () or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates. Surface damage Before the instrumental pe ...

was on the coastline near Hualien, which was the most severely affected area, with a maximum felt intensity of VIII (''Severe'') on the

Mercalli intensity scale 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 ...

. At least 17 deaths were reported, with 285 injured. The maximum

foreshock A foreshock is an earthquake that occurs before a larger seismic event (the mainshock) and is related to it in both time and space. The designation of an earthquake as ''foreshock'', ''mainshock'' or aftershock is only possible after the full sequ ...

was recorded on 4 February 2018, at 21:56:40. The epicenter was located at Hualien County, Taiwan, reaching a scale of M_L 5.8.

Tectonic setting

has a history of many strong earthquakes. The island is located within a complex zone of convergence between the

Philippine Sea Plate The Philippine Sea Plate or the Philippine Plate is a tectonic plate comprising oceanic lithosphere that lies beneath the Philippine Sea, to the east of the Philippines. Most segments of the Philippines, including northern Luzon, are part of ...

and

Eurasian Plate The Eurasian Plate is a tectonic plate that includes most of the continent of Eurasia (a landmass consisting of the traditional continents of Europe and Asia), with the notable exceptions of the Indian subcontinent, the Arabian subcontinent and ...

. At the location of the earthquake, these plates converge at a rate of 75 mm per year. To the south of Taiwan,

oceanic crust Oceanic crust is the uppermost layer of the oceanic portion of the tectonic plates. It is composed of the upper oceanic crust, with pillow lavas and a dike complex, and the lower oceanic crust, composed of troctolite, gabbro and ultramafic cumu ...

of the Eurasian Plate is

subducting Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the ...

beneath the Philippine Sea Plate creating an

island arc Island arcs are long chains of active volcanoes with intense seismic activity found along convergent tectonic plate boundaries. Most island arcs originate on oceanic crust and have resulted from the descent of the lithosphere into the mantle alon ...

, the Luzon Arc. At Taiwan the oceanic crust has all been subducted and the arc is colliding with

continental crust Continental crust is the layer of igneous, sedimentary, and metamorphic rocks that forms the geological continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called ''sial'' be ...

of the Eurasian Plate. To the north of Taiwan the Philippine Sea Plate is in contrast subducting beneath the Eurasian Plate, forming the Ryukyu Arc.

Earthquake

The earthquake formed the largest of a sequence of events that have affected the area over a period of days, with 11

s of M 4.6 and greater, starting on 3 February with an M 4.8 earthquake and including an M 6.1 event on 4 February, within a few kilometres of the event that took place on 6 February. 6 February earthquake was a result of oblique-slip faulting. The earthquake occurred on the second anniversary of the 2016 Taiwan earthquake in Tainan that had killed 117 people. The earthquake was followed by a series of aftershocks, with the largest being an M 5.7 event on 7 February at 23:21 local time, 19 km northeast of Hualien city, which reached a maximum intensity of VI (''strong''). File:2018 Hualien earthquake.svg,

Richter magnitude The Richter scale —also called the Richter magnitude scale, Richter's magnitude scale, and the Gutenberg–Richter scale—is a measure of the strength of earthquakes, developed by Charles Francis Richter and presented in his landmark 1935 ...

s of the 2018 Hualian earthquakes. Source: Taiwan Central Weather Bureau File:Map of 2018 Hualian earthquake.svg, Map of 2018 Hualian earthquakes as of 9 February (UTC+8) plotting 359 shocks. Source: Taiwan Central Weather Bureau File:Hualien 2018 foreshocks and aftershocks.png, Maps of 2018 Hualian fore-, main, and aftershocks: on the right, the location of M>4.5

s and the mainshock (red star); on the left, M>4.5 aftershocks (as of 18:00 UTC 9 February) and the mainshock. Both maps are from USGS earthquake catalog results.

Aftermath

Casualties

As of 11 February 17 people were reported dead and a further 285 injured. Of the reported fatalities, 9 were from

People's Republic of China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

, 5 from Taiwan, 2 from

Hong Kong Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China ( abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delt ...

Canadian Canadians (french: Canadiens) are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of ...

nationality, and 1 from the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

. 14 of them were in The Yun Men Tsui Ti building.

Damage

Many buildings in the city of Hualien were damaged, including four that had partially collapsed or were severely damaged. The lower floors of the Marshal Hotel collapsed, killing two people. 14 deaths were also reported from the twelve-story Yun Men Tsui Ti (雲門翠堤) residential building, which was severely tilted due to the collapse of some of the lower floors. Large beams were placed by cranes on one side of the building in an effort to prevent further tilting during the continuing rescue efforts. Many homes were left without water. Bridges and highways remaining closed due to damage from the earthquake. Hundreds of firefighters and military personnel stayed onsite to support efforts to rescue people trapped in damaged buildings.

International response

The Taiwanese government said that several countries offered to provide aid following the earthquake but stated that it had to "politely decline" such offers, including an offer from People's Republic of China reasoning that Taiwan has no shortage of relief workers and supplies. It decided to accept a Japanese contingent since they possess body-heat detection equipment, a technology Taiwanese authorities do not possess. The Japanese specialized rescue team arrived on 9 February to provide assistance for the search efforts. The Japanese team was the first international search-and-rescue team to arrive in Taiwan. Singapore also flew in US$103,000 worth of humanitarian supplies to Taiwan through a

C-130 Hercules The Lockheed C-130 Hercules is an American four-engine turboprop military transport aircraft designed and built by Lockheed Corporation, Lockheed (now Lockheed Martin). Capable of using unprepared runways for takeoffs and landings, the C-130 ...

of the

Republic of Singapore Air Force The Republic of Singapore Air Force (RSAF) is the aerial service branch of the Singapore Armed Forces (SAF) responsible for controlling and defending the airspace of the country, and providing air support to the Army and Navy. It was establish ...

. At least 63 countries, 18 of which have formal diplomatic ties with Taiwan, as well as the

European Union The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been des ...

, the

Organization of Eastern Caribbean States The Organisation of Eastern Caribbean States (OECS; French: ''Organisation des États de la Caraïbe orientale'', OECO) is an inter-governmental organisation dedicated to economic harmonisation and integration, protection of human and legal ri ...

, the

Central American Parliament The Central American Parliament ( es, Parlamento Centroamericano), also known as PARLACEN, is the political institution and parliamentary body of the Central American Integration System (SICA). Its headquarters are in Guatemala City. History ...

and the

Central American Integration System The Central American Integration System ( es, Sistema de la Integración Centroamericana, or SICA) has been the economic and political organization of Central American states since 1 February 1993. On 13 December 1991, the ODECA countries (Spa ...

sent condolences to the Taiwanese government.

References

External links

* * {{Earthquakes in Taiwan Hualien Hualien Hualien Hualien Hualien County Hualien City