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"The oldest ice found in drilled cores is around 800,000 years old and with this new technique we think we can look in other regions and successfully date polar ice back as far as 1.5 million years," said Christo Buizert, a postdoctoral researcher at Oregon State University and lead author on the PNAS article. Through Polar Programs, NSF manages the United States Antarctic Program, which coordinates all U. research on the southernmost continent and the logistical support for the science.
"That is very exciting because a lot of interesting things happened with the Earth's climate prior to 800,000 years ago that we currently cannot study in the ice-core record."The work was supported by two collaborative awards 08389031 made by the Division of Polar Programs in NSF's Geosciences Directorate and by the U. Buizert, whose work also was supported in part by the National Oceanic and Atmospheric Administration, said reconstructing the Earth's climate back to 1.5 million years is important because a shift in the frequency of ice ages took place in what is known as the Middle Pleistocene transition.
Local relationships on a single outcrop or archaeological site can often be interpreted to deduce the sequence in which the materials were assembled.
Unlike carbon-14, however, Krypton is a Noble gas that does not interact chemically and is much more stable with a half-life of around 230,000 years, Buizert pointed out.
Carbon dating doesn't work well on ice because carbon-14 is produced in the ice itself by cosmic rays.
(The number in superscript preceding the element name indicates the atomic mass, the sum of its protons and neutrons.) Alpha decay releases a Helium nucleus (two protons and two neutrons) from the parent atom to create two atoms: the released Helium and a daughter product that has an atomic number two less than the original and an atomic mass four less than the original. Some creationists claim that there is too much helium in Earth's crust for the earth to be any more than two million years old (Sarfati, 2005).
If Earth has existed for billions of years, there should be little helium left in deeper rocks as a result of radioactive alpha decay.
organisms, geologists employ a variety of techniques.