Astride A Plate Boundary
New Zealand is currently astride the convergent boundary between the Pacific and Australian Plates. The Pacific Plate is subducted beneath the Australian Plate from around Samoa and Tonga in the north, through the Tonga Trench, Kermadec Trench, and Hikurangi Trough to the east of the North Island of New Zealand, down to Cook Strait, and the Marlborough Sounds and Kaikoura region. Through most of the South Island, the plates slide past each other, with slight obduction of the Pacific Plate over the Australian Plate, forming the Alpine Fault and Southern Alps. From Fiordland south, the Australian Plate subducts under the Pacific Plate forming the Puysegur Trench.
Over time, the position of the plate boundary has altered. Around 23 Ma, the convergent plate boundary formed Northland. Around 10 Ma, the Coromandel Ranges were formed. Activity has now moved further East, generating the Kermadec Ridge and Trench, and the Taupo Volcanic Zone. The Southern Alps are quite recent, only forming in the last 10 million years.
Read more about this topic: Geology Of New Zealand
Famous quotes containing the words astride, plate and/or boundary:
“They give birth astride of a grave, the light gleams an instant, then it’s night once more.”
—Samuel Beckett (1906–1989)
“Say “Yessum” to the ladies, an’ “Yessur” to the men,
And when they’s company, don’t pass yer plate for pie again;
But, thinkin’ of the things yer’d like to see upon that tree,
Jes ‘fore Christmas be as good as yer kin be!”
—Eugene Field (1850–1895)
“It appeared that he had once represented his tribe at Augusta, and also once at Washington, where he had met some Western chiefs. He had been consulted at Augusta, and gave advice, which he said was followed, respecting the eastern boundary of Maine, as determined by highlands and streams, at the time of the difficulties on that side. He was employed with the surveyors on the line. Also he called on Daniel Webster in Boston, at the time of his Bunker Hill oration.”
—Henry David Thoreau (1817–1862)