
A
Mw 6.4 earthquake struck the island of
Lombok
Lombok is an island in West Nusa Tenggara province, Indonesia. It forms part of the chain of the Lesser Sunda Islands, with the Lombok Strait separating it from Bali to the west and the Alas Strait between it and Sumbawa to the east. It is ...
on the morning of 29 July 2018 at a shallow depth of . Widespread damage was reported in the area, and authorities confirmed that 20 people were killed in the earthquake while hundreds were injured.
The
epicentre
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 located in Sembalun Subdistrict,
East Lombok Regency
East Lombok Regency is a regency ( id, Kabupaten) of the Indonesian Province of West Nusa Tenggara. It is located on the island of Lombok, of which it comprises the eastern third (including minor offshore islands); the administrative capital is th ...
. The earthquake was a
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 ...
to the larger 6.9 earthquake
which struck the island a week later.
Tectonic setting
Lombok lies on the
destructive plate boundary
A convergent boundary (also known as a destructive boundary) is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a p ...
between the
Australian Plate
The Australian Plate is a major tectonic plate in the eastern and, largely, southern hemispheres. Originally a part of the ancient continent of Gondwana, Australia remained connected to India and Antarctica until approximately when India broke ...
and the
Sunda Plate
The Sunda Plate is a minor tectonic plate straddling the Equator in the Eastern Hemisphere on which the majority of Southeast Asia is located.
The Sunda Plate was formerly considered a part of the Eurasian Plate, but the GPS measurements have ...
. To the east of
Bali
Bali () is a province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller neighbouring islands, notably Nusa Penida, Nusa Lembongan, and Nu ...
the plate boundary starts to involve a collision between the leading edge of the Australian
continent
A continent is any of several large landmasses. Generally identified by convention rather than any strict criteria, up to seven geographical regions are commonly regarded as continents. Ordered from largest in area to smallest, these seven ...
and the eastern part of the
Sunda Arc
The Sunda Arc is a volcanic arc that produced the volcanoes that form the topographic spine of the islands of Sumatra, Nusa Tenggara, and Java, the Sunda Strait and the Lesser Sunda Islands. The Sunda Arc begins at Sumatra and ends at Flores, ...
and the western end of the
Banda Arc
The Banda Arc (main arc, Inner, and Outer) is a set of island arcs in eastern Indonesia. It is the result of the collision of a continent and an intra-oceanic island arc. The presently active arc is located on what appears to be oceanic crust wh ...
. In response to this collision, the arc itself has begun to be pushed over the
back-arc Bali Basin along a major
thrust fault
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks.
Thrust geometry and nomenclature
Reverse faults
A thrust fault is a type of reverse fault that has a dip of 45 degrees or less.
If ...
, the long Flores Thrust. The Lombok earthquake has been attributed to movement along the
Flores Thrust.
[
]
Earthquake
The earthquake struck on Sunday, at 06:47 local time, at a shallow depth of . Residents reported severe shaking near the epicentre, with multiple structures reportedly collapsed. Dozens of houses were destroyed and widespread damage was reported. The shaking lasted 10–20 seconds. Local residents have said it was the strongest quake to have ever hit Lombok. The earthquake was felt as far away as Denpasar
Denpasar (; Balinese: ᬤᬾᬦ᭄ᬧᬲᬃ) is the capital of Bali and the main gateway to the island. The city is also a hub for other cities in the Lesser Sunda Islands.
With the rapid growth of the tourism industry in Bali, Denpasar has e ...
, Bali
Bali () is a province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller neighbouring islands, notably Nusa Penida, Nusa Lembongan, and Nu ...
. and in Karangasem Regency
Karangasem Regency (Indonesian: ''Kabupaten Karangasem'') is a regency (''kabupaten'') of Bali, Indonesia. It covers the east part of Bali, has an area of 839.54 km2 and had a population of 396,487 at the 2010 Census which rose to 492,402 ...
, Bali, a temple collapsed and a local court was damaged.
Landslides struck the north portion of Mount Rinjani
Mount Rinjani ( id, Gunung Rinjani) is an active volcano in Indonesia on the island of Lombok. Administratively the mountain is in the Regency of North Lombok, West Nusa Tenggara (Indonesian: ''Nusa Tenggara Barat'', NTB). It rises to , making ...
, where routes popular with hiking tourists are located. Authorities confirmed that 826 hikers were trapped on the mountain and waited to be rescued.
In Selong
Selong is a town on the island Lombok and is also the capital of the East Lombok Regency in the Indonesian province West Nusa Tenggara.
Climate
Selong has a tropical savanna climate
Tropical savanna climate or tropical wet and dry climate is a ...
, the capital of East Lombok Regency
East Lombok Regency is a regency ( id, Kabupaten) of the Indonesian Province of West Nusa Tenggara. It is located on the island of Lombok, of which it comprises the eastern third (including minor offshore islands); the administrative capital is th ...
, dozens of patients were evacuated from dr. Soedjono regional hospital while in Sembalun a Community Health Centre was significantly damaged.
Authorities confirmed that 276 moderate aftershocks from 5.0–5.5 Mw were recorded by the Indonesian Agency for Meteorology, Climatology and Geophysics
Meteorology, Climatology, and Geophysical Agency ( id, Badan Meteorologi, Klimatologi, dan Geofisika, abbreviated BMKG) is an Indonesian non-departmental government agency for meteorology, climatology, and geophysics.
History
Its history began ...
(BMKG). The largest aftershock at a magnitude 5.7 Mw recorded at 10:16 local time. On 3 August, officials confirmed that more than 500 aftershocks had been recorded.
Casualties
Authorities confirmed that a Malaysian tourist was killed by a falling wall. The Indonesian National Board for Disaster Management
The National Agency for Disaster Countermeasure (Indonesian: ''Badan Nasional Penanggulangan Bencana''; officially National Disaster Management Agency), abbreviated as BNPB, is the Indonesian board for natural disaster affairs. It was establish ...
(BNPB) confirmed that 10 people were killed and 40 people were injured. The government confirmed that 18 Malaysians were affected by the earthquake.
On the evening of 29 July, officials announced that the number of people who had been killed by the earthquake had risen to 16. Later the number rose to 17, then 20 on 5 August.
Aftermath
In the aftermath of the earthquake, blackouts occurred throughout Lombok and telecommunications went down. The National Electricity Company (PLN) stated that they would temporarily cut the electricity in East Lombok Regency for examination. They later announced that normal operation would resume within hours.
The government immediately closed the Mount Rinjani National Park
Mount Rinjani National Park is located on the island of Lombok, Indonesia in the North Lombok Regency. The park covers about and consists of mountainous areas. Mount Rinjani (''Gunung Rinjani''), which is the third highest volcano of Indonesia ...
. Hiking and other activities were banned in the area due to fear of landslides. Indonesian President Joko Widodo
Joko Widodo (; born 21 June 1961), popularly known as Jokowi, is an Indonesian politician and businessman who is the 7th and current president of Indonesia. Elected in July 2014, he was the first Indonesian president not to come from an elit ...
, who had planned to visit West Nusa Tenggara prior to the earthquake, ordered Muhammad Zainul Majdi
Muhammad Zainul Majdi (born 31 May 1972) is an Indonesian
Indonesian is anything of, from, or related to Indonesia, an archipelagic country in Southeast Asia. It may refer to:
* Indonesians, citizens of Indonesia
** Native Indonesians, divers ...
, the Governor of West Nusa Tenggara
West Nusa Tenggara ( id, Nusa Tenggara Barat – NTB) is a province of Indonesia. It comprises the western portion of the Lesser Sunda Islands, with the exception of Bali which is its own province. Mataram, on Lombok, is the capital and largest ...
to immediately deploy search and rescue personnel to the affected areas.
Authorities stated on 29 July 2018, that East Lombok Regency had suffered the most damage. Sembalun District and Sambelia District were regarded as the worst affected areas in the regency. Hundreds of tents were set up while dozens of search and rescue personnel, including members from the Indonesian Armed Forces, police and other government institutions, were deployed onto the declared disaster zone.
On 29 July 2018, Bali Red Cross announced that they would send medical experts and volunteers to Lombok.
Indonesian Social Minister Idrus Marham confirmed that the government would send multiple aids to the victims.
On 30 July, Joko Widodo
Joko Widodo (; born 21 June 1961), popularly known as Jokowi, is an Indonesian politician and businessman who is the 7th and current president of Indonesia. Elected in July 2014, he was the first Indonesian president not to come from an elit ...
, the Indonesian President, Muhammad Zainul Majdi the Governor of West Nusa Tenggara, and Idrus Marham, the Social Minister visited survivors and victims of the earthquake and sent condolences to the affected families. Majdi declared a state emergency for three days. They distributed books and other supplies to survivors and later examined the damage. Joko Widodo later announced that the government would help the victims rebuild their houses and infrastructures in Lombok. On 31 July he stated that the government would immediately provide compensation of at least 50 million rupiah for each damaged or destroyed building. The renovation of the damaged buildings would be assisted by the Indonesian National Armed Forces
, founded = as the ('People's Security Forces')
, current_form =
, disbanded =
, branches =
, headquarters = Cilangkap, Jakarta
, website =
, commander-in-chief = Joko Widodo
...
.
Spokesman of the BNPB, Sutopo Purwo Nugroho
Sutopo Purwo Nugroho (7 October 1969 – 7 July 2019) was an Indonesian civil servant and academic who worked at the Indonesian National Board for Disaster Management as its head of public relations.
An alumnus of Gadjah Mada University and Bogo ...
, stated that more than 1,000 structures across Lombok were either damaged or destroyed. BMKG advised people not to enter their homes as more aftershocks are expected in the following days.
The Malaysian government through their Prime Minister Mahathir Mohamad
Mahathir bin Mohamad ( ms, محاضير بن محمد, label= Jawi, script=arab, italic=unset; ; born 10 July 1925) is a Malaysian politician, author, and physician who served as the 4th and 7th Prime Minister of Malaysia. He held the office ...
have announced that aid would be sent to the Indonesian people who were affected by the earthquake, with Mercy Malaysia
MERCY Malaysia or Malaysian Medical Relief Society is a non-profit organisation focusing on providing medical relief, sustainable health related development and risk reduction activities for vulnerable communities in both crisis and non-crisi ...
also began to distribute essential relief items for the victims. The Malaysian Global Peace Mission (GPM) deployed a team to identify the urgent needs of victims, with an initial RM10,000 aid, and an additional RM50,000 brought the following week by a second aid team.
On 5 August 2018 a Mw 6.9 or 7.0 earthquake struck Lombok, prompting tsunami warnings.
Search and rescue
The Indonesian National Search and Rescue Agency
The National Search and Rescue Agency ( id, Badan Nasional Pencarian dan Pertolongan, literally translated Search and Rescue National Agency; formerly named ''Badan SAR Nasional'', both abbreviated Basarnas) is a government agency of Indonesia. ...
(SAR) announced that there were two main locations where trapped hikers were located. The first one was in Segara Anak Lake while the second one was at the basecamp. As of 30 July more than 700 hikers were on the mountain, of whom 100 were from Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...
, the United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...
, and other countries. SAR stated that they had prepared two helicopters for the evacuation process and that at least 500 hikers had been evacuated from the mountain.
There were confusions among officials on the number of hikers on the mountain, as it was reported that most hikers were not registered by their tour guides. Several media stated that around 600 hikers were on the mountain, while another stated that there were around 500 people. Officials later finalized the total number to more than 1,200 hikers of whom around 700 of them were foreigners from 26 countries, the majority are Thais. Government officials stated that around 300 Thais were on the mountain during the disaster.
On 1 August, all 1,226 hikers had been rescued from the mountain.
References
External links
*
*
{{DEFAULTSORT:2018 Lombok earthquake, July
2018 disasters in Indonesia
2018 earthquakes
2018 in Indonesia
Earthquakes in Indonesia
July 2018 events in Indonesia
West Nusa Tenggara
Landslides in Indonesia