Potassium argon dating problems
27-Jan-2020 08:03
We use cookies to make interactions with our website easy and meaningful, to better understand the use of our services, and to tailor advertising.For further information, including about cookie settings, please read our Cookie Policy .Eruptions from a central 400 m diameter crater have constructed the steep (33°) outer slopes of the cone.34 The Taupo Volcanic Zone, a volcanic arc and marginal basin of the Taupo-Hikurangi arc-trench (subduction) system,5 is a southward extension on the Tonga-Kermadec arc into the continental crustal environment of New Zealand’s North Island.
Solid triangles are basalt-andesite volcanoes.15 11 North-northeast-trending normal faults with throws up to 30 m cut the volcanoes within the graben.
1).12 Though not as well publicized as its neighbor, Mt.
Ruapehu (about 12 km to the south), Ngauruhoe is an imposing, almost perfect cone that rises more than 1000 m above the surrounding landscape.
Potassium-argon “dating” of five of these flows and deposits yielded K-Ar model “ages” from Ar* content.
A survey of anomalous K-Ar “dates” indicates they are common, particularly in basalts, xenoliths, and xenocrysts such as diamonds that are regarded as coming from the upper mantle.Activity decreased for two months after the last of the lava flows on September 26, but increased again during December 1954 and January 1955 with lava fountaining and many highly explosive pyroclastic (ash) eruptions.
