Start What is potassium argon dating

What is potassium argon dating

Ngauruhoe is the newest cone of the Tongariro massif and has been active for at least 2.5 ka.2126 Prior to European colonization the Maoris witnessed many eruptions from the mountain.27 The first lava eruption seen by European settlers occurred between April and August 1870, with two or three flows witnessed spilling down the northwestern flanks of the volcano on July 7.2832 The southern sub-crater filled with lava, which by late on February 10 had flowed over the lowest part of the rim and down the northwest slopes of the cone.

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.

It has been interpreted as oblique subduction of the Pacific plate beneath the Australian plate.

The results demonstrate that the technique is capable of achieving KAr dates as young as 2000 a with a few centuries accuracy.

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.

The zone extends approximately 300 km north-northeast across the North Island from Ohakune to White Island (fig.

1) and is up to 50 km wide in the central part, narrowing northward and southward. Ngauruhoe in the Taupo Volcanic Zone (TVZ), New Zealand, showing the main structural features.

Nearly all vents active within the last 10 ka lie on a gentle arc which extends 25 km north-northeast from the Rangataua vent on the southern slopes of Ruapehu through Ruapehu summit and north flank vents, Tama Lakes, Ngauruhoe, Red Crater, Blue Lake, and Te Mari craters.