Sonoma orogeny Sonoma orogeny The Sonoma orogeny was a period of mountain building in western North America. The exact age and structure of the Sonoma orogeny is controversial. The orogeny is generally thought to have occurred during the Permian / Triassic transition, around 250 million years ago, following the Late Devonian Antler orogeny. The Sonoma orogeny was one of a sequence of accretionary events along the Cordilleran margin, possibly caused by the closure of the basin between the island arc of Sonomia and the North American continent. Evidence of this event has been reported throughout western North America, but most distinctly in
Kaikoura Orogeny million years ago to the present day the rate of uplift has accelerated. Oligoclase and biotite schist have also been pushed to the surface of the Earth. In total about 20 kilometres of uplift has taken place during the Kaikoura Orogeny but most of this has been eroded away. Kaikoura Orogeny The Kaikoura Orogeny is a New Zealand orogeny that has given birth to the Southern Alps. It began 25 million years ago along the Alpine Fault. In this orogeny, the Southern Alps are being formed because the Pacific Plate is colliding with the Australian Plate, with a predominant oblique