Palaeozoic and Proterozoic zircons from the Mid-Atlantic Ridge
Article Abstract:
The theory of plate tectonics states that rocks found close to mid-ocean ridges, where oceanica plates are formed, should be only a few million years old. A new discovery of zircons found in the vicinity of the Mid-Atlantic Ridge shows ages of around 330 and 1,600 million years. It is suggested that these unusually old zircons could have been exposed as a result of upshearing or could have been trapped within the Kane fracture zone following a series of transform fractures.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1998
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Evolution of the Altaid tectonic collage and Palaeozoic crustal growth in Eurasia
Article Abstract:
Eurasia grew by about 5.3 million square km during the Palaeozoic era. Nearly half this growth came from juvenile crust drawn from the mantle. Study of the Altaids, a geological structure surrounding the ancient core of Eurasia, suggests that giant subduction-accretion complexes grew along an arc from Siberia to the Baltic. These systems may have contributed up to 48% of the Earth's continental growth during their active period.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1993
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