Evidence from coupled 147Sm-143Nd and 146Sm-142 Nd systematics for very early (4.5-Gyr) differentiation of the Earth's mantle
Article Abstract:
It has been thought that the Earth remained undifferentiated until 4.5 billion years ago, when the crust was thought to have started growing. But the isotope ratio of neodymium indicates that by 3.8 billion years ago 40% of the present crust had formed. This fact, together with an analysis of the ratio of samarium 147 to neodymium 143, suggests that the Earth began differentiating about 4.5 billion years ago.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
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The noble art of recycling
Article Abstract:
Well gases from the upper mantle of the Earth were investigated to challenge an established tenet concerning the existence of a 'subduction barrier' that prevents noble gases from recycling into the mantle through tectonic activity. It was found that the recycling of noble gases into the mantle reservoirs by subduction has n ever been proved.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2006
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Lost terrains of early Earth
Article Abstract:
Isotope data supply insight into the earliest aspects of terrestrial evolution. The most recent reappraisal buttresses the opinion that the early Earth possessed a cratered crust that crystallized from a magma ocean.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2003
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