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Ambae Island and Lombenben Volcano

Flood and explosion at Voui Lake  |  Voui Lake: 50 million cubic meter of acid water  |  Recent resumption of volcanic activity  |  Real-time satellite
monitoring of the volcano

Recent resumption of volcanic activity

A resumption of volcanic activity has been observed since 1990 in the crater lake Voui. This has resulted in deforestation of the lake's islets, and of the western shores downwind of the acid gases. A photograph taken on March 20, 1995,  seventeen days after the phreatic explosion (itself limited to the ejection of chunks of sediment over the summit area) shows the substantial rise in temperature of the water, evidenced by a lowering of the lake's level due to increased evaporation. The level dropped by 7 metres, representing a volume of 13,500 m3 of water. By the beginning of June 1995, the water was still at a temperature of 40°C.
Along with this resumption of activity in the lake in 1991, a near-surface quake (magnitude 4.8) was recorded on December 4, 1994. It was centered in the vicinity of Ambae and was followed by several after-shocks. The quake was strongly felt by the population, particularly in the northern districts of the island. It triggered an alert, which was maintained for several months, a period during which another phreatic explosion occurred (March 3, 1995). By late March, the tremors were observed to decrease in intensity, and the alert level was downgraded. In the end, no one among the 9000 residents of the island threatened by the volcano needed to be evacuated.

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