Monte Burney
[10] The strongest volcanic eruption in the region occurred 7,750 years before present at Cerro Hudson volcano,[11] which deposited tephra all over southern Patagonia and Tierra del Fuego.
[12] This eruption probably caused a major depopulation of Tierra del Fuego, the temporary disappearance of long-range obsidian trade, and a change in the prevalent lifestyles of the region.
[17][10] In terms of composition, Lautaro, Aguilera and Viedma form one group distinct from Burney, and Reclus lies between these two.
[18] 420 kilometres (260 mi) southeast of Monte Burney lies Fueguino, a volcanic field with possible historical activity in 1820 and 1712.
[19] Large explosive eruptions have occurred at Aguilera, Reclus and Burney but due to the long distance between these volcanoes and critical infrastructure they are considered a low hazard.
[20][14] A 6 kilometres (3.7 mi) wide caldera lies in the area, which is partly filled by pyroclastic flows.
[1] It is not a simple volcanic cone,[7] has its own summit caldera[21] with a crescent of spires,[7] and a steep wall on the northern side with uncertain origin.
[20] In the case of Monte Burney, these magmas then underwent some fractionation during ascent, as it was retarded by the tectonic regimen, which is somewhat compressive.
Polar cold air outbreaks, cool ocean upwelling, orographic precipitation and the Antarctic Circumpolar Current further affect the regional climate.
[36] According to the Potrok Aike record, Monte Burney may be the most active volcano in the region during the late Quaternary.
[44] The MB2 eruption may have formed the summit caldera as well as tephra deposits exceeding 5 metres (16 ft) of thickness east of the volcano.
[48][39] Both the MB1[49] and MB2 eruptions may have affected the settlement patterns of prehistoric humans in the region,[50] driving them to areas with more predictable resources.
[52] Fires leaving charcoal in bogs on Tierra del Fuego[53] and a sulfate spike in an Antarctic ice core around 4,100 ± 100 years before present may have been caused by MB2.
[58] Further findings were made at Ushuaia, Brunswick Peninsula,[59] a number of other sites[60] and for MB1 on the Falklands Islands about 950 kilometres (590 mi) away from Monte Burney.
[40] Tephra from an eruption that occurred about 2,000 years before present reached a thickness of 12 centimetres (4.7 in) in a peat bog 70 kilometres (43 mi) away from Monte Burney.
[65] Two tephras at Fiordo Vogel and Seno Skyring have been linked to Monte Burney; they are dated 4,254 ± 120 and 9,009 ± 17 - 9,175 ± 111 years before present.
[68] A reworked tephra identified at Hooker's Point, East Falkland, may come from a mid-Holocene eruption that took place between the MB1 and MB2 events.
[69] Reports from natives, mentioned in 1847, of a volcano at the end of a bay that makes the ground tremble probably refer to Monte Burney, which is visible on clear days from Almirante Montt Gulf [es].
[72] The mountain was already known before 1871; a book written in that year by Robert Oliver Cunningham records the following travel report mentioning Monte Burney:[73] the entire mass of a magnificent solitary mountain a little to the northward, in general shrouded more or less in mist, and the summit of which we had never seen, was revealed, without a cloud to dim the dazzling splendour of its jagged snowy peaks, the extensive snow-fields which clothed its sides and the deep blue crevassed glaciers which filled its gorges.The appearance of the mountain was considered "majestic" in 1899.
[75] Eric Shipton explored the area in 1962, and after a failed attempt in 1963 climbed Monte Burney on 10 March 1973, reaching its summit together with Peter Radcliffe and Roger Perry.
