This article is about the mountain in Central Java Island. For the mountain in West Sumatra, seeMount Marapi.
Mount MerapiHighest pointElevationProminenceListingCoordinatesNamingEnglish translationLanguage of nameGeographyGeologyAge of rockMountain typeLast eruption
Mount Merapi, colour lithograph, Junghuhn and Mieling, 1853–1854
Mount Merapi,Gunung Merapi(literallyFire MountaininIndonesianandJavanese), is anactivestratovolcanolocated on the border betweenCentral JavaandSpecial Region of Yogyakartaprovinces,Indonesia. It is the most active volcano in Indonesia and has erupted regularly since 1548. It is located approximately 28 kilometres (17 mi) north ofYogyakartacity which has a population of 2.4 million, and thousands of people live on the flanks of the volcano, with villages as high as 1,700 metres (5,600 ft) abovesea level.
Smoke can often be seen emerging from the mountaintop, and several eruptions have caused fatalities. Pyroclastic flow from a large explosion killed 27 people on 22 November 1994, mostly in the town of Muntilan, west of the volcano.[3]Another large eruption occurred in 2006, shortly before theYogyakarta earthquake. In light of the hazards that Merapi poses to populated areas, it has been designated as one of theDecade Volcanoes.
On 20 October 2010, the Indonesian government raised the alert for Mount Merapi to its highest level and warned villagers in threatened areas to move to safer ground. People living within the range of a 20 km (12 mi) zone were told to evacuate. Officials said[who?]about 500 volcanic earthquakes had been recorded on the mountain over the weekend of 23–24 October[vague], and that the magma had risen to about 1 kilometre (3,300 ft) below the surface due to the seismic activity.[4]On the afternoon of 25 October 2010, Mount Merapi eruptedlava from its southern and southeastern slopes.[5]
The mountain was still erupting on 30 November 2010, but due to lowered eruptive activity on 3 December 2010, the official alert status was reduced to level 3.[6]The volcano is now 2930 metres high,[2]38 metres lower than before the 2010 eruptions.
After a large eruption in 2010, the characteristic shape of Mount Merapi was changed. On 18 November 2013, Mount Merapi erupted smoke up to 2,000 meters high, one of its first majorphreatic eruptionsafter the 2010 eruption. Researchers said that this eruption occurred due to the combined effect of hot volcanic gases and abundant rainfall.[7]The most recent eruptions so far were on 3 March 2020[8][9]and 27 March 2020.[10]
The nameMerapicould be loosely translated as the Mountain of Fire. The etymology of the name came fromMeru-Api; from the ancient classical language of India Sanskrit andJavanesecombined words;Merumeans "mountain", refers to mountain of Gods in Hinduism, andapimeans "fire".
Merapi is the youngest in a group of volcanoes in southernJava. It is situated at asubductionzone, where theIndo-Australian Plateis subducting under theSunda Plate. It is one of at least 129 active volcanoes in Indonesia, part of the volcano is located in the Southeastern part of the Pacific Ring of Fire–a section of fault lines stretching from the Western Hemisphere through Japan and South East Asia.[11]Stratigraphic analysis reveals that eruptions in the Merapi area began about 400,000 years ago, and from then until about 10,000 years ago, eruptions were typically effusive, and the out flowinglavaemitted wasbasaltic. Since then, eruptions have become more explosive, with viscousandesiticlavas often generatinglava domes. Dome collapse has often generatedpyroclastic flows, and larger explosions, which have resulted ineruption columns, have also generated pyroclastic flows through column collapse.
Typically, small eruptions occur every two to three years, and larger ones every 10–15 years or so. Notable eruptions, often causing many deaths, have occurred in 1006, 1786, 1822, 1872, and 1930. Thirteen villages were destroyed in the latter one, and 1,400 people were killed by pyroclastic flows.
Merapi in 1930
The very large eruption in 1006 is claimed to have covered all of central Java withash. The volcanic devastation is claimed to have led to the collapse of theHinduKingdom of Mataram; however, the evidence from that era is insufficient for this to be substantiated.
In April 2006, increasedseismicityat more regular intervals and a detected bulge in the volcano's cone indicated that fresh eruptions were imminent. Authorities put the volcano's neighboring villages on high alert and local residents prepared for a likely evacuation. On 19 April smoke from the crater reached a height of 400 metres (1,300 ft), compared to 75 metres (246 ft) the previous day. On 23 April, after nine surface tremors and some 156 multifaced quakes signalled movements of magma, some 600 elderly and infant residents of the slopes were evacuated.[12]
By early May, active lava flows had begun. On 11 May, with lava flow beginning to be constant, some 17,000 people were ordered to be evacuated from the area[13]and on 13 May, Indonesian authorities raised the alert status to the highest level, ordering the immediate evacuation of all residents on the mountain.[14]Many villagers defied the dangers posed by the volcano and returned to their villages, fearing that their livestock and crops would be vulnerable to theft.[11]Activity calmed by the middle of May.[15]
On 27 May, a6.3 magnitude earthquakestruck roughly 50 km (31 mi) southwest of Merapi, killing at least 5,000 and leaving at least 200,000 people homeless in theYogyakartaregion, heightening fears that Merapi would "blow".[16]The quake did not appear to be a long-period oscillation, a seismic disturbance class that is increasingly associated with major volcanic eruptions. A further 11,000 villagers were evacuated on 6 June as lava and superheated clouds of gas poured repeatedly down its upper slopes towards Kaliadem, a location that was located southeast of Mt. Merapi.[17]The pyroclastic flows are known locally as "wedhus gembel" (Javanese for "shaggy goat"). There were two fatalities as the result of the eruption.
Destroyed house in Cangkringan Village after the eruptions
In late October 2010 the Center for Volcanology and Geological Hazard Mitigation, Geological Agency (CVGHM), (Indonesian language—Pusat Vulkanologi & Mitigasi Bencana Geologi, Badan Geologi-PVMBG), reported that a pattern of increasing seismicity from Merapi had begun to emerge in early September.
Observers at Babadan 7 kilometres (4.3 mi) west andKaliurang8 kilometres (5.0 mi) south of the mountain reported hearing anavalancheon 12 September 2010. On 13 September 2010 white plumes were observed rising 800 metres (2,600 ft) above the crater. Lava dome inflation, detected since March, increased from background levels of 0.1 millimetres (0.0039 in) to 0.3 millimetres (0.012 in) per day to a rate of 11 millimetres (0.43 in) per day on 16 September. On 19 September 2010 earthquakes continued to be numerous, and the next day CVGHM raised the Alert Level to 2 (on a scale of 1–4).[18]Lava from Mount Merapi inCentral Javabegan flowing down the Gendol River on 23–24 October signalling the likelihood of an imminenteruption.[19]
On 25 October 2010, the Indonesian government raised the alert for Mount Merapi to its highest level (4) and warned villagers in threatened areas to move to safer ground. People living within a 10 kilometres (6.2 mi) zone were told to evacuate. The evacuation orders affected at least 19,000 people; however, the number that complied at the time remained unclear to authorities.[20]Officials said about 500 volcanic earthquakes had been recorded on the mountain over the weekend of 23–24 October, and that themagmahad risen to about 1 kilometre (3,300 ft) below the surface due to the seismic activity[21]
After a period of multiple eruptions considered to exceed the intensity and duration of those in 1872[22]on 10 November 2010 the intensity and frequency of eruptions was noticed to subside.[23]By this time 153 people had been reported to have been killed and 320,000 were displaced.[24]Later the eruptive activities again increased requiring a continuation of the Level 4 alert and continued provision of exclusion zones around the volcano.[25][26]By 18 November the death toll had increased to 275.[27]The toll had risen to 324 by 24 November and Syamsul Maarif, head of the National Disaster Mitigation Agency (BNPB) explained that the death toll had risen after a number of victims succumbed to severe burns and more bodies were found on the volcano's slopes.[28]
In the aftermath of the more intensive eruptive activities in late November, Yogyakarta's Disaster Management Agency reported that there were about 500 reported cases of eruption survivors in Sleman district suffering from minor to severe psychological problems, and about 300 cases in Magelang.[28]By 3 December the death toll had risen to 353.[29]
On Friday, 3 December 2010, the head of the National Disaster Management Agency (BNPB), Dr. Syamsul Maarif, M. Si, accompanied by the head of the Centre for Volcanology and Geological Hazard Mitigation CVGHM (PVMBG), Dr. Surono made a joint press release at the BNPB Command Post in Yogyakarta. As of 3 December 2010, at 09.00 am, the CVGHM (PVMBG) lowered the status of Mount Merapi to the level of Caution Alert (Level III). They clarified that with this alert level the potential of hot ash clouds and projected incandescent material remained. The Geological Agency provided several recommendations including that there would be no community activities in the disaster prone areas and proclaimed an ongoing exclusion zone of 2.5 kilometres (1.6 mi) radius.[30]
This image shows some of the instruments deployed by the Deep Carbon Degassing Project in the vicinity of Mount Merapi in 2014.
Mount Merapi is the site of a very active volcano monitoring program.Seismicmonitoring began in 1924, with some of the volcano monitoring stations lasting until the present. The Babadan (northwest location), Selo (in the saddle betweenMerbabuand Merapi), andPlawanganmonitoring stations have been updated with equipment over the decades since establishment. During the 1950s and early 1960s some of the stations were starved of equipment and funds, but after the 1970s considerable improvement occurred with the supply of new equipment. Some of the pre-1930 observation posts were destroyed by the 1930 eruption, and newer posts were re-located. Similarly after the 1994 eruption, the Plawangan post and equipment were moved intoKaliurangas a response to the threat of danger to the volcanological personnel at the higher point. This volcano is monitored by theDeep Earth Carbon Degassing Project.
The eruption of 1930 was found to have been preceded by a large earthquake swarm. The network of 8seismographscurrently around the volcano allow volcanologists to accurately pinpoint thehypocentresof tremors and quakes.
A zone in which no quakes originate is found about 1.5 km below the summit, and is thought to be the location of themagma reservoirwhich feeds the eruptions.
Other measurements taken on the volcano includemagneticmeasurements and tilt measurements. Small changes in the local magnetic field have been found to coincide with eruptions, and tilt measurements reveal the inflation of the volcano caused when the magma chambers beneath it is filling up.
Lahars(a type ofmudflowof pyroclastic material and water) are an important hazard on the mountain, and are caused byrainremobilizing pyroclastic flow deposits. Lahars can be detected seismically, as they cause a high-frequencyseismic signal. Observations have found that about 50 mm of rain per hour is the threshold above which lahars are often generated.
There are about 90 units (30 percent) from the total 258 units of sand barriers (sabo) were damaged. The cost for recovery is about Rp.1 trillion ($116 million).[34]
Following the 2010 eruption, three Indonesian government departments declared a prohibited zone which nobody can permanently stay and no infrastructure is allowed in 9 villages (dusun): Palemsari, Pangukrejo, Kaliadem, Jambu, Kopeng, Petung, Kalitengah Lor, Kalitengah Kidul and Srunen, all in Cangkringan district.[35]
In 2004, an area of 6,410 hectares around Mount Merapi was established as anational park. The decision of the Ministry of Forestry to declare the park has been subsequently challenged in court byThe Indonesian Forum for Environment, on grounds of lack of consultation with local residents.[36]During the 2006 eruption of the volcano it was reported that many residents were reluctant to leave because they feared their residences would be confiscated for expansion of the national park, meaning they wouldn't have a house.[37]
Merapi Museum Center,KaliurangStreet Kilometer 25.7,Pakemsubdistrict,Sleman,Yogyakarta. A replica of Merapi's Post 2010 Eruption has been created and Indonesian student visits to the museum has increased 30 percent since the latest eruption.[38]
Although most nearby villages have their own myths about the creation of Mount Merapi, they have numerous commonalities. It is believed that when the gods had just created the Earth,Javawas unbalanced because of the placement of Mount Jamurdipo on the west end of the island. In order to assure balance, the gods (generally represented byBatara Guru) ordered the mountain to be moved to the centre of Java. However, two armourers, Empu Rama and Empu Permadi, were already forging a sacredkerisat the site where Mount Jamurdipo was to be moved. The gods warned them that they would be moving a mountain there, and that they should leave; Empu Rama and Empu Permadi ignored that warning. In anger, the gods buried Empu Rama and Empu Permadi under Mount Jamurdipo; their spirits later became the rulers of all mystical beings in the area. In memory of them, Mount Jamurdipo was later renamed Mount Merapi, which means "fire of Rama and Permadi."[39]
The Javanese believe that the Earth is not only populated by human beings, but also by spirits (makhluk halus). Villages near Merapi believe that one of the palaces (inJavanesekraton) used by the rulers of the spirit kingdom lies inside Merapi, ruled by Empu Rama and Empu Permadi. This palace is said to be a spiritual counterpart to theYogyakarta Sultanate, complete with roads, soldiers, princes, vehicles, and domesticated animals. Besides the rulers, the palace is said to also be populated by the spirits ofancestorswho died as righteous people. The spirits of these ancestors are said to live in the palace as royal servants (abdi dalem), occasionally visiting their descendants in dreams to givepropheciesor warnings. "[40]
To keep the volcano quiet and to appease the spirits of the mountain, the Javanese regularly bring offerings on the anniversary of the sultan ofYogyakarta's coronation.[41]ForYogyakarta Sultanate, Merapi holds a significant cosmological symbolism, because it forms a sacred north-south axis line between Merapi peak and Southern Ocean (Indian Ocean). The sacred axis is signified by Merapi peak in the north, theTugu Yogyakartamonument near Yogyakarta main train station, the axis runs alongMalioborostreet to Northern Alun-alun (square) acrossKeratonYogyakarta (sultan palace), Southern Alun-alun, all the way to Bantul and finally reach Samas and Parangkusumo beach on the estuary of Opak river and Southern Ocean. This sacred axis connected thehyangsor spirits of mountain revered since ancient times—often identified as "Mbah Petruk" by Javanese people—The Sultan of Yogyakarta as the leader of the Javanese kingdom, andNyi Roro Kidulas the queen of the Southern Ocean, the female ocean deity revered by Javanese people and also mythical consort of Javanese kings.[42]
François Beauducel & François-Henri Cornet-Institut de Physique du Globe de Paris, Dpt Seismology, Edi Suhanto, Made Agung-Volcanological Survey of Indonesia, Constraint from displacement data on magma flux at Merapi volcano, Java.[43]
François Beauducel and François-Henri Cornet-Département de Sismologie, Institut de Physique du Globe de Paris, France. Edi Suhanto, Made Agung-Volcanological Survey of Indonesia, Bandung, Indonesia. T. Duquesnoy and M. Kasser-Institut Géographique National, St-Mandé, France. Java, Indonesia, Journal of Geophysical research, (Vol unknown) 2000, Constraints on magma flux from displacements data at Merapi volcano[44]
Camus G, Gourgaud A, Mossand-Berthommier P-C, Vincent P-M, 2000. Merapi (central Java, Indonesia): an outline of the structural and magmatological evolution, with a special emphasis to the major pyroclastic events. J Volc Geotherm Res, 100: 139–163
Charbonnier S J, Gertisser R, 2008. Field observations and surface characteristics of pristine block-and-ash flow deposits from the 2006 eruption of Merapi volcano, Java, Indonesia. J Volc Geotherm Res, 177: 971–982
Gertisser R, Keller J, 2003. Temporal variations in magma composition at Merapi volcano (Central Java, Indonesia): magmatic cycles during the past 2000 years of explosive activity. J Volc Geotherm Res, 123: 1–23
Lavigne F, Thouret J C, Voight B, Suwa H, Sumaryono A, 2000. Lahars at Merapi volcano, central Java: an overview. J Volc Geotherm Res, 100: 423–456
Newhall C G, Bronto S, Alloway B, Banks N G, Bahar I, del Marmol M A, Hadisantono R D, Holcomb R T, McGeehin J, Miksic J N, Rubin M, Sayudi S D, Sukhyar R, Andreastuti S, Tilling R I, Torley R, Trimble D, Wirakusumah A D, 2000. 10,000 years of explosive eruptions of Merapi volcano, central Java: archaeological and modern implications. J Volc Geotherm Res, 100: 9–50
Siswowidjoyo S, Suryo I, Yokoyama I, 1995. Magma eruption rates of Merapi volcano, Central Java, Indonesia during one century (1890–1992). Bull Volc, 57: 111–116
Thouret J-C, Lavigne F, Kelfoun K, Bronto S, 2000. Toward a revised hazard assessment at Merapi volcano, central Java. J Volc Geotherm Res, 100: 479–502
Triyoga, Lucas Sasongko. 1991Manusia Jawa dan Gunung Merapi – Persepsi dan Sistem KepercayaannyaYogyakarta, Gadjah Mada University Press.ISBN979-420-211-8
US Army, Corps of EngineersArmy Geospatial Center[45]webpage on the crisis of Mount Merapi, with data, citations, photographs and maps.
Voight B, Constantine E K, Siswowidjoyo S, Torley R, 2000. Historical eruptions of Merapi volcano, central Java, Indonesia, 1768–1998. J Volc Geotherm Res, 100: 69–138
Wirakusumah A D, Juwarna H, Loebis H, 1989. Geologic map of Merapi volcano, Central Java. Volc Surv Indonesia, 1:50,000 geol map
^BNPB (9 November 2010)."Rekor Baru Letusan Merapi"(in Indonesian). Badan Koordinasi Nasional Penanganan Bencana-Indonesian Disaster Management Office. Retrieved9 November2010.
^Triyoga, Lucas Sasongko (2010).Merapi dan Orang Jawa: Persepsi dan Kepercayaannya(in Indonesian). Jakarta: Gramedia Widiasarana Indonesia. pp. 50–52.
^Triyoga, Lucas Sasongko (2010).Merapi dan Orang Jawa: Persepsi dan Kepercayaannya(in Indonesian). Jakarta: Gramedia Widiasarana Indonesia. pp. 56–60.
^Mount Tourism – Mount Merapi. Ministry of Culture and Tourism. 2008.
^Triyoga, Lucas Sasongko (1991) Manusia Jawa dan gunung merapi : persepsi dan kepercayaannya Yogyakarta : Gadjah Mada University Press.ISBN979-420-211-8, see also Khairuddin, H. (1995) Filsafat Kota YogyakartaISBN979-499-180-5page 58 (in Indonesian) – Gunung Merapi sebagai terminal akhir dalam prosesSumbu Imajinerdiyakini pula sebagaiSurga pangratunan, yang berasal dari kataantu, yang artinya menanti, yakni menanti sevelum roh diinjinkan masuk surga, yaitu kembali kepada Sang Pencipta.
