Be cosmogenic dating


04-Apr-2016 01:59

This long period of applicability is an added advantage of cosmogenic nuclide dating.Cartoon illustrating cosmogenic nuclide exposure ages. A glacier transports an erratic boulder, and then recedes, exposing it to cosmic rays.Cosmogenic nuclides are rare nuclides that form in surface rocks because of bombardment by high-energy cosmic rays[3].Surface exposure dating is a collection of geochronological techniques for estimating the length of time that a rock has been exposed at or near Earth's surface.Cosmogenic isotopes are created when elements in the atmosphere or earth are bombarded by high energy particles (-mesons and protons, collectively known as cosmic rays) that penetrate into the atmosphere from outer space.Some cosmic ray particles reach the surface of the earth and contribute to the natural background radiation environment.Until just 20 years ago, when pioneering work in accelerator mass spectrometry (Elmore and Phillips, 1987), cosmogenic isotope systematics (Lal, 1988), and geologic applications (Craig and Poreda, 1986; Kurz, 1986) hit the presses, such conclusions were unreachable because many hypotheses regarding rates and dates of glacial processes were simply unfalsifiable.

They used protruding mountains as chronometric dipsticks (e.g., Stone et al., 2003), analyzing the Al content of submeter erratics left behind as the East Antarctic Ice Sheet lowered.No Derivative works ‒ You may not alter, transform, or build upon this work.