Sentences with phrase «uranium isotope ratio»
The study by Andersen and his colleagues is the first to use the uranium isotope ratio for the examination of igneous rock and apply it to the recycling process in deep Earth.
https://www.sciencedaily.com/ Not exact matches
Grind a few flecks of calcite off a cave painting, measure the ratio of uranium and thorium isotopes, and you can read out the age of the calcite.
By applying uranium - thorium dating to the corals and measuring ratios of oxygen isotopes in their skeletons, her lab reconstructed ocean temperatures for much of the last 7000 years.
In particular, the researchers found that a higher ratio of uranium - 238 to uranium - 235 is incorporated into the modern oceanic crust, when compared to the uranium isotope signature found in meteorites.
For this work, conducted at the University of Bristol including Morten Andersen (now Earth Science, ETH Zurich) along with researchers from the Durham (UK), Wyoming and Rhode Island (US), used the «fingerprint» carried in the ratio of the two uranium isotopes.
By comparing the ratio of protactinium - 231 to thorium - 230, two daughter isotopes of uranium decay that remain in seawater for relatively short but consistently different periods of time before drifting into the seafloor, they could determine when circulation was strongest.