"It helps us understand the evolution of Earth and Earth's atmosphere, and evolution of life, for that matter." Chamberlain's contribution focuses on igneous rocks exposed in South Africa that record the existence of equatorial glaciers and contain chemical indicators for the rise of atmospheric oxygen.Chamberlain's in situ method to determine the age of the rocks does not require removing baddeleyite crystals from the rock.(no offence to the hard working souls who created it).There is a huge middle section that goes off on a technical tangent about a time lag, and only near the end do we get to the explanation of what actually happened.If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.This article is part of Wiki Project Evolutionary biology, an attempt at building a useful set of articles on evolutionary biology and its associated subfields such as population genetics, quantitative genetics, molecular evolution, phylogenetics, and evolutionary developmental biology.
The research relates to a period in Earth's history about 2.45 billion years ago, when climate swung so extremely that the polar ice caps extended to the equator and Earth was a snowball, and the atmosphere was largely isolated from the hydrosphere, Chamberlain says.This situation is part of the trigger for the "Snowball Earth" conditions."There are glacial deposits exposed in the Medicine Bow Mountains and Sierra Madre that are from this same event," he says.This process allows for analysis of key samples with smaller crystals than previously allowed.Using a mass spectrometer, the age of the rocks is determined by measuring the buildup of lead from the radioactive decay of uranium, he says.
"The basic story had been worked out earlier by others, but our results have significantly refined the timing and duration of the 'event,' which is more of a transition actually," Chamberlain explains.