1979 eruption of Sinila crater | |
---|---|
Volcano | Dieng Volcanic Complex, |
Date | 20 February 1979 |
Location | Central Java, Indonesia |
VEI | 1 [1] |
Impact | 175 [2] [3] –180 [4] [5] deaths (up to 800+ deaths have been reported [6] ) 1,000+ injured [2] [3] 17,000 evacuated [2] [4] |
During the night of 20 February 1979, the Sinila volcano of the Dieng Volcanic Complex erupted on the Indonesian island of Java in Central Java province. Over 175 people died, mainly due to gas poisoning in villages on the plateau near the Sinila crater. [7] [8] It was the fourth Sinila eruption since 1928, and the first one since 1951. [9] [3] This complex sits on a subduction zone between the Australian and Eurasian plates. [10]
The eruption started in the early morning, with 3 earthquakes before the initial explosion at 5 in the morning [10] . The eruption involved explosions, the expulsion of rocks and mud, intense steam and gas release, and a hot lahar that flowed over roads and farmland along a 3.5 km stretch [10] . A new crater was created, measuring approximately 90 m in diameter and 100 m deep. A new vent, 15 meters in width, formed after a second but minor eruption at 6:45 am, in the Sigludug area [11] . Mud and stones were expelled and a small lahar was released. During the eruption, the Sumur crater, which was initially dormant, got reactivated and started showing activity when carbon dioxide emissions started to occur [12] .
During the eruption, toxic gases were emitted from the crater for two days. Carbon Dioxide emissions continued for several months after the initial explosion. Voluminous amounts of carbon dioxide started to emerge from both the fracture and the Sigluduk crater and sheets of the dense gas flowed down to the Batur plain [12] . Gases were still released for several months after the explosion. These gases were sampled in early July, during the time they were being emitted [12] . The gas was made up of carbon dioxide, methane, and hydrogen sulfide. These craters are known for emitting toxic gases, which are dangerous for the people living nearby.
The eruption came unexpectedly as the Sinila volcano was considered extinct already for a long time. [2] The eruption followed after seven earthquakes and an explosion. [13] Two explosions occurred within an hour of each other, causing a lahar lava flow. [10] Next to lava, toxic gas was released which could be seen, smelled or tasted. [4] As the eruption took place during the night, people inhaled the poisonous gases during their sleep and died. The village with the most deaths was Pucukan, where bodies were also lying on the streets. [13] The rescue work was made difficult due to toxic gases and difficulty accessing the area. [13] At some places the streets were covered by an 8-metre (26 ft) layer of lava. [2] The worst affected village was Pekasiran, which was inaccessible due to the mud and lava. [14] [15]
Rescue work was also hampered due to a lack of gas masks. [4] Policemen, soldiers and volunteers were killed by the gases due to the absence of enough gas masks. [3]
A few days after the eruption, the death toll rose to 180. [4] Some sources even stated over 800 deaths. [6] According to an expert, most people died due to panic after the eruption. It was later discovered that 142 people among the casualties died due to the toxic gas sheets when they were fleeing along a trail from the village of Kepucukan towards the Batur village. [12]
People went to higher ground to flee the lava but were killed by the toxic gas. [4] Over 1,000 people were injured, [2] and many people were hospitalized. [13] The Indonesian government ordered that an area of 3 kilometres (1.9 mi) around the mountain be evacuated, affecting around 17,000 people. [11] [2] President Suharto stated that around 6,000 people had been evacuated by February 22nd. Evacuation efforts were hampered due to lava severing main roads, restricting access to the area.
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