Sentences with phrase «zircons show»

Minerals and isotopes in these zircons show that water and granite were also present.38 The extremely low ratio of 13C to 12C suggests that all these carbon isotopes were not originally present.

Portrait of a young planet The Jack Hills zircons show that a magnetic field existed as early as 4 billion years ago, fluctuating in strength from a value similar to today's — around 25 microteslas — to about 12 % of that.

Not exact matches

The scientists identified 656 zircons containing dark specks that could be revealing and closely analyzed 79 of them with Raman spectroscopy, a technique that shows the molecular and chemical structure of ancient microorganisms in three dimensions.

Measurements on some 50 grains of zircon from the gneiss rocks found in Canada showed them to be 3.962 billion years old, with a margin of error of only three million years.

Careful radioactive dating shows that these zones formed essentially simultaneously, even in Hadean zircons of different ages, Mojzsis says.