Radioactive dating in antarctica
Of course, no geologist was present to test this assumption by observing ancient lavas when they cooled, but we can study modern lava flows. To also test the consistency of results within samples, second pieces of two of the 30 June 1954 lava samples were also sent for analysis. No specific location or expected age information was supplied to the laboratory.Geochron is a respected commercial laboratory, the K–Ar lab manager having a Ph. However, the samples were described as probably young with very little argon in them so as to ensure extra care was taken during the analytical work.Yes, what’s amazing is by ruling out terrestrial and cosmogenic sources of iron-60, they could show the presence of recent iron-60 with interstellar origin in Antarctica for the first time.
Mt Ngauruhoe is thought to have been active for at least 2,500 years, with more than 70 eruptive periods since 1839, when European settlers first recorded a steam eruption.Explosions of ash completed this long eruptive period. Cannon-like, highly explosive eruptions in January and March 1974 threw out large quantities of ash as a column into the atmosphere, and as avalanches flowing down the cone’s sides.Blocks weighing up to 1,000 tonnes were hurled 100 m (330 feet).The radioactive potassium-argon dating method has been demonstrated to fail on 1949, 1954, and 1975 lava flows at Mt Ngauruhoe, New Zealand, in spite of the quality of the laboratory’s K–Ar analytical work.Argon gas, brought up from deep inside the earth within the molten rock, was already present in the lavas when they cooled.
If any of these assumptions are violated, then the technique fails and any ‘dates’ are false. Eleven samples were collected from five recent lava flows during field work in January 1996—two each from the 11 February 1949, 4 June 1954, and 14 July 1954 flows and from the 19 February 1975 avalanche deposits, and three from the 30 June 1954 flow (Figure 6).