Akshay's Gyaan: Nov 5, 2010

Posted by Alutsyah Luthfian

Merapi

Merapi, a volatile volcano located at the northernmost border between Yogyakarta and Central Java. The name Merapi cames from Old Javanese term "Meru" which mean mountain and "Api" which mean fire. So the term Merapi itself means Mountain of Fire. Its legend of eruption starts from 1006 AD (120 AD?) when the collapse of Old Merapi volcano killed as much as 3000 lives. The New Merapi then growing and erupting with short pause. Merapi is an basic-intermediate volcano which height is 2968 m. It started to grow from the floor of ocean circa 700,000 years ago. At that time, just like another oceanic volcanoes its lava is basaltic. This basic basaltic lava created a broad base of Old Merapi volcano which is now visible as hilly terrain of Western Boyolali regency. After the collapse of Old Merapi, its characteristics change. Its lava then "more acidic" and has higher viscosity. This filled the big caldera left by the Old Merapi rapidly.

Merapi's eruption has its own characteristic. It grows a lava dome before an eruption. The lava dome's growth fasten rapidly when the lava is near the earth surface, thus it indicates the the D day of eruption will not wait any longer and villagers living 5 km from Merapi's summit must be evacuated, especially those who live in southern flank. On the eruption day, the lava dome collapses and pyroclastic flow roll down its flank (mostly southern flank). After the lava dome collapsed, then glimmers of lava emanate from its summit. If rain with amount more than 50 mm occurs when Merapi erupt, then lahar will flood many creeks up to 10 kilometers away from its source and threaten many sand-miners of Sleman Regency.

Also, some people living in the flank of Merapi could hear a "harmonic noise" created by magma finding its path to the earth surface a couple weeks before its eruption day. They called this sound as "Jathilan Song" and they have to run down from Merapi flank rapidly after hearing the noise.

This 2010 eruption have predicted by me one month before (September). It was a morning when i went to Jakarta from Klaten, my ancestors' town. I see that Merapi looked unusual: it spewed more smoke than it does on ordinary days.

"Hi dad.."

"What's wrong?", said my dad.

"I'm sure that Merapi will erupt this year"

"How can you said that?", my father replied me with confusion.

"See its smoke. That's all."

Entire people inside my car keep silent.

Then I posted my prediction on Merapi at the end of September and the early October. Everyone commented on my post with confusion. To reduce wrong interpretation of my post and gossips, i delete that post hastily.

OCTOBER 26, 2010, 17.02 GMT+7

Blarr! The sound of swiftly-rolling (200 km/h) hot (800 K) pyroclastic cloud of Mount Merapi signed the start of its eruption. After bulging 42 cm a day before, its summit lava dome finally collapse and spewed hot cloud to the South flank. It killed 31 lives in Kinahrejo and Umbulharjo community.

OCTOBER 27, 2010

Merapi's ash cloud is blown to West (because of Westerly Wind above the PBL which is common in tropical area), disrupting train in Purworejo, Central Java province by putting ash on railway switcher, causing it to fail. Ash is also reported to fall in Ciamis, West Java, some 250 km away from Merapi.

OCTOBER 30, 2010

For the second time, Merapi started its new episode of explosive eruption on October 30, 2010 at 12.16 - 12.34 AM GMT+7. In this second explosive eruption, the ash plume reached the height of 3,5 KM and rain of sand fell in Sleman Regency of Yogyakarta. Ash from second eruption disrupted aircraft transportation in Adisucipto Airport of Yogyakarta, causing it to be closed from 12 PM up to 02 PM GMT+7. Also, a plane departing from Adisumarmo airport of Surakarta was serviced in Hang Nadim airport of Batam because of ash from Merapi filthed its machines and body. Until the time this article written, there are 78 times of material collapse, 27 times of multiphase earthquake, once shallow volcanic earthquake and 3 times of deep volcanic earthquake.

OCTOBER 31, 2010

Pyroclastic cloud happened twice, the first is at 02.45 p.m. and the second 03.15 p.m (GMT+7). Each of them happened as long as 10 minutes. Those times' pyroclastic flows is directed to east and south east.

Until November 4, 2010, Merapi still emit pyroclastic clouds and rain of sand still happened in Magelang (since upper level wind is directed to West). Cold lahar has arrived at the city of Yogyakarta at November 3, 2010.

on November 5, 2010, Dangerous Zone of Merapi was broaden up to 20 km from its crater. At 12.45 AM, a bang was heard 30 km away followed by huge fireball emanating from Merapi's summit and after that, rain of stones fell in Merapi's flank. Ash plume's height was 9 km, thus 41 flights from Adisucipto Airport of Yogyakarta is cancelled. Also, lightning flashes lit the city of Muntilan on the northwestern Merapi flank. At 03.00 AM, the village of Argomulyo (17 km from crater) was swept by pyroclastic cloud. At noon, Ash and dust fell as far as Bandung (320 km from Merapi). Inhabitants of Yogyakarta is prohibited to approach the area 300 meters surrounding the River Code because of cold lahar. Refugees in Yogyakarta has been moved to the provincial capital and its surroundings.

By November 5, 2010 afternoon, the ash from Merapi has reached Puncak, Bogor (400 km from Merapi).

2010 eruption of Merapi Data

VEI : 4 (the worst eruption since 1872)

Volume of Ejecta: 100 million cubic meters

Type of eruption : Explosive

Lava type : Andesitic (intermediate)

Evacuated: 100,000+ inhabitants

Victims: 109 inhabitants.

Characteristic of ash: slippery because of high content of Silica and fractions of Obsidian stones.

MASTER MARIJAN

Javanese culture is full of supernatural things, including there in geophysics circumstances. In Javanese culture, upcoming geophysics phenomena could be mitigated by the coming of a "holy dream" to the "holy man", in which the dream tells him about how affecting is the phenomenon to the people. The "holy man" then tells the people to be ready for the phenomenon. One of this "holy man" is Master Marijan or Master Penewu Suraksohargo (Old Javanese noble man title meaning "A master which lead some communities that can retain his nobelity"). He is the caretaker of Merapi volcano from 1983 up to his death (aged 83) in his prayer when pyroclastic cloud swept his house on October 26, 2010. He is well known by the Indonesians because of his debut in 2006 Eruption of Merapi volcano. He was refused to be evacuated and said that 2006 eruption is not harmful and prove it by climb the mountain and went back with no injury. Starting from that time, he signed some contracts with TV programs and advertisements.

Master Marijan died in his charge "keeping the Merapi" and his loyality to his holiness KingHamengku Buwono X (Old Javanese term meaning "the Manajer of the World") of Yogyakarta. He has knew that Merapi will erupt this 2010 a couple of weeks before October 26, and also knew that this 2010 eruption will swept away his house because a triangular stone capping a lava dome is lost. He has asked many people to run down from Merapi flank. Some people died at the eruption are the ones who was refused to run down because they want to accompany the Master. When the condition of Merapi goes eerie, evacuators ask Master Marijan to run down quickly, but he said that he will run down if the king asked him to do so because of his loyality to the king.

At the time of sunset on October 26, the king asked Master to run down because the condition of Merapi is very eerie. But the Master said, "I want to do the 5th prayer first. Please wait." The pyroclastic flow swept his house when he was praying. His corpse is found in the kitchen at the position of prostrating.

As a caretaker of Merapi Volcano and a noble man in Yogyakarta Kingdom, Master Marijan has some restrictions. The restrictions are: He should not has luxurious living, Do some meditations, Loyal to the king, and Do strict fastings. This restrictions are intended for him to get closer to the nature of Merapi Volcano.

PREDICTION

I hope that Merapi eruption lasts no longer than 2 - 3 weeks (around November 10- 20, 2010). Though the pressure of Merapi still stored in magma chamber, but it has an outlet today, so the pressure of eruption could be reduced and flow constantly outside until the volcano reach stability.

VIDEO OF MERAPI ERUPTION SEEN FROM BOYOLALI

(narration in Indonesian)

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