https://freerepublic.com/tag/coloradoplateau/ en-us Fri, 23 Aug 2019 01:45:52 GMT Focus Forum 15 https://freerepublic.com/focus/f-chat/3773778/posts Scientists have found that increasing oxygen levels are linked to the rise of North American dinosaurs around 215 M years ago. A new technique for measuring oxygen levels in ancient rocks shows that oxygen levels in North American rocks leapt by nearly a third in just a couple of million years, possibly setting the scene for a dinosaur expansion into the tropics of North America and elsewhere... The US-based scientists have developed a new technique for releasing tiny amounts of gas trapped inside ancient carbonate minerals. The gases are then channelled directly into a mass spectrometer, which measures their composition.... EurekAlert! https://freerepublic.com/focus/f-chat/3773778/posts#comment Fri, 23 Aug 2019 01:45:52 GMT