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Mount Lamington is an andesitic stratovolcano in the Oro Province of Papua New Guinea. The forested peak of the volcano had not been recognised as such until its devastating eruption in 1951 that caused about 3,000 deaths. The volcano rises to 1680 meters above the coastal plain north of the Owen Stanley Range. A summit complex of lava domes and crater remnants rises above a low-angle base of volcaniclastic deposits that are dissected by radial valleys. A prominent broad avalanche valley extends northward from the breached crater.
The mountain was named after Charles Cochrane-Baillie, 2nd Baron Lamington who was Governor of Queensland.
In early January 1951, a series of minor explosions and earthquakes rocked Mount Lamington, a volcano in Oro Province, Territory of Papua and New Guinea. Prior to the eruption, Mount Lamington was not recognized as a volcano due to the absence of historically-recorded eruptions and dense vegetation cover.
From January 15, volcanic activity intensified, and tall eruption plumes were generated. The largest eruption occurred on the morning of January 21 when a thick black plume of ash rose 15,000 m into the atmosphere.
The eruption collapsed a lava dome and produced a lethal pyroclastic flow that killed 2,942 people. In the years after the eruption, new lava domes formed and collapsed in succession. Activity persisted until July 1956. The eruption is the deadliest natural disaster in Australian history, as the region was under the rule of the Government of Australia.
Volcanism in Papua New Guinea is due to the ongoing subduction of oceanic crust beneath the island due to plate tectonics.
Mount Lamington is situated within the Hydrographers Range; a small, forested coastal mountain range. The mountain range is the remnant of a heavily eroded Quaternary stratovolcano.
The dominant rock types are andesite and basaltic andesite. While a majority of the range's eruptive history occurred during the Pleistocene, the presence of cinder cones and craters on the southern flank of the range suggest volcanism also took place during the Holocene. The mountain lies adjacent to the Owen Stanley Range. Nearby volcanoes include Mount Suckling and Mount Victory.
More information: Volcano Hotspot
Mount Lamington rises to a height of 1,680 meters above the coastal flats north of the Owen Stanley Range. A summit complex of lava domes and crater remnants rises above a low-angle base of volcaniclastic deposits that are dissected by radial valleys. A prominent broad avalanche valley extends northward from the breached crater. The horseshoe-shaped crater was the result of a large prehistoric sector collapse.
Prior to the eruption in 1951, Mount Lamington was not known by locals to be an active volcano as no widespread ancient folklore or stories of the volcano existed among the native population. The only indication of volcanic activity was a small hot spring on the northern slopes, which was not known by most of the native population.
There were also settlements located on the flank of the volcano. A weak hint of its volcanic nature was a traditional story, related to the volcano's activity, of a lake on the summit which exploded, destroying villages and killing many people. The native population regards the mountain as a sacred and spiritual place.
Geologists however, understood that Mount Lamington and the Hydrographers Range were volcanic in origin, and that it was a geologically young feature. A geologist from the Netherlands classified Mount Lamington an active volcano. Only three eruptions were confirmed in the Holocene.
A number of inhabitants around Mount Lamington reported earthquakes in early January 1951. One eyewitness also saw a strange light on New Year's Day of 1951.
More information: PNGAA
On the morning of January 15, residents saw evidence of landslides in the crater wall of the volcano. Landslide scars identified as streaks of brown in the heavily forested volcano flank indicated the volcano was active. At a rubber plantation in Sangara, a village, a person reported white smoke or vapour cloud rising from the base of the volcano. Around the crater, vegetation was killed by the intense heat emitted from the ground.
The following day, January 16, a vapour cloud was seen from Higaturu. Large landslides were reported, many destroying the existing vegetation. The entire rainforest around the crater was destroyed by the late afternoon. An earthquake swarm occurred at 16:00. Up to 30 earthquakes were felt till 08:00 on January 17. Stronger earthquakes were felt in Isivita Mission, located northwest of the crater.
On January 17, an ash column rising between some hills and Mount Lamington was observed. The column grew larger as the hours passed. Earthquakes continued to be felt, and there was a red glow observed at night. By January 18, large plumes of dark grey ash ejected from the volcano. A large explosion occurred in the morning. A newly-constructed volcanic hill where volcanic material escaped was observed. The eruptions did not cause any human deaths, according to District Commissioner Cecil Cowley on January 19. Large columns of ash rising 6,100-7,600 m could be observed from Popondetta.
From Kokoda, the eruption was described as a large black column, and had a shape reminiscent of a cauliflower. Monsoon winds caused heavy ashfall on the southern side of the volcano. Some settlements where the Orokaiva people lived were damaged.
The most violent eruption occurred four days later at 10:40 local time. Occupants on two Qantas Empire Airways flights which flew in close proximity to the erupting volcano reported a large eruption column and base surge of pyroclastic debris. The captain of a Douglas DC3 flight witnessed a massive continuous column of black smoke erupting from the crater. The column rose over 4,300 m, punching through a layer of clouds. In two minutes, the column had risen 12,000 m from the crater, and expanded into a mushroom column. The captain of the DC 3 radioed authorities at Port Moresby about the sequence of events. Another Qantas flight; a de Havilland Dragon bound for Popondetta from Lae, was about to land when its occupants witnessed the side of volcano blow itself apart. A large surge of debris approached the aircraft, forcing its return to Lae.
The post-January 21 eruptive phase consisted of explosive eruptions which produced pyroclastic flows. A large pyroclastic flow was documented on March 5, 1951. After the climactic eruption on January 21, a new lava dome formed in the crater. The new lava dome grew to fill the crater.
From 1951 to 1953, new lava domes formed and collapsed, generating more pyroclastic flows. The dome eventually attained a height of 450 metres from the crater floor to its summit and had a volume of 0.2 km3. A lava spine emerged from the dome and grew to a height of 150 m. Lava spines continuously formed and were destroyed over a five-year period.
Rough estimates of the death toll appeared as early as 23 January which suggested 4,000 deaths. A thorough count did not happen because bodies were buried within days to weeks of the disaster. Port Moresby officials conveyed to the Department of External Territories; 3,466 people dead or missing. An administration official in Port Moresby performed an investigation of the local population from August to October and concluded that 2,907 people died. The total death toll amounted to 2,942.
More information: Smithsonian Institution-Global Volcanism Program
until the lava actually overtakes them.
George Santayana
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