The Lost Worlds
During the Jurassic, the original "Pangaea" super-continent split into 4 main pieces: Laurentia (North America), Baltica, Siberia and Gondwana - large rafts of the earth's crust, "floating" on the planet's molten interior.
This map shows how the modern southern continents fitted together - as confirmed by exact correlations between rock and mineral formations, now separated by thousands of miles and major oceans.
Gondwanaland - How the Continents Fitted Together
Wikipedia has ths comment on climate: "During the late Paleozoic, Gondwana extended from a point at or near the south pole to near the equator. Across much of Gondwana, the climate was mild. During the Mesozoic, the world was on average considerably warmer than today. Gondwana was then host to a huge variety of flora and fauna for many millions of years."
During the mid Jurassic - about 167,000,000 years ago - while things were still pretty warm, this large continent also began to break up, with the eastern portion, comprising Antarctica, Madagascar, India and Australasia, slowly separating from Africa and South America, before the individual continents gradually split away from each other.
At the southern end of this huge landmass was a geosyncline - we call it the Andean Geosyncline to the west and the New Zealand Geosyncline to the east. This is an area of subsidence in the earth's crust. In this active subduction zone, the edge of the crust is constantly being drawn back into the hotter regions of the mantle below. And there's little old New Zealand sitting right in it!
It's this process that feeds volcanic activity - hence the volcanoes along the west coast of South America and the clear linear arrangement of volcanoes in Aotearoa.
 
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