Posted by Don Keyes on September 03, at Do you know if ice core dating is accurate? I heard that Antarctica had ice rings like tree rings that go back 50, years undisturbed by a flood. If it is challenged do you know on what basis? An ice core of over 2km in length has been drilled and carefully analysed. Yes, the number of layers indicates many tens of thousands of years.
Dating by annual layer counting
Dating by annual layer counting – University of Copenhagen
I was wondering how ice cores are dated accurately. I know Carbon 14 is one method, but some ice cores go back hundreds of thousands of years. Would other isotopes with longer half-lives be more accurate? Also, how much does it cost to date the core? How are samples acquired without destroying the ice? I imagine keeping the ice intact as much as possible would be extremely valuable.
Ice Cores and the Age of the Earth WW II Planes
Figure 1 Scientists measure ice cores from deep drilling sites on the ice sheet near Casey station Photo by M. Antarctica is the coldest, windiest, highest and driest continent on Earth. That's right - the driest! Antarctica is a desert. The annual precipitation of snow, averaged across the continent, is about 30 centimetres, which is equivalent to about 10 centimetres of water.
An ice core is a core sample that is typically removed from an ice sheet or a high mountain glacier. Since the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper, and an ice core contains ice formed over a range of years. Cores are drilled with hand augers for shallow holes or powered drills; they can reach depths of over two miles 3. The physical properties of the ice and of material trapped in it can be used to reconstruct the climate over the age range of the core. The proportions of different oxygen and hydrogen isotopes provide information about ancient temperatures , and the air trapped in tiny bubbles can be analysed to determine the level of atmospheric gases such as carbon dioxide.