Radiocarbon dating is based on the principle that 14C (or carbon-14), an unstable radiometric isotope of 12C, is produced in the earth’s upper atmosphere due to cosmic ray bombardment (Libby et al., 1949). From: Forensic Anthropology (Second Edition), 2019 ...
ra·di·o·met·ric dating (rā′dē-ō-mĕt′rĭk) A method for determining the age of an object based on the concentration of a particular radioactive isotope contained within it. The amount of the isotope in the object is compared to the amount of the isotope's decay products. The...
…greatly from the use of radiometric-dating techniques, which are based on the principle that a particular radioisotope (radioactive parent) in geologic material decays at a constant known rate to daughter isotopes. Using such techniques, investigators have been able to determine the ages of variou...
也可见: dating 名 — 约会 名 查看更多用例 • 查看其他译文 © Linguee 词典, 2024 ▾外部资源(未审查的) Comparison with more discriminating radiometric measures of attenuation can be made routinely. unesdoc.unesco.org 因此,提供给实时模拟人员的数据只是种类有限的参数(目前大多数是物 理学参数...
Does radiometric dating prove the earth is old?Riddle, Mike
Absolute dating using scientific processes to determine an exact age or an age within a tight range. Relative dating uses the position of rock in a set of strata to determine its age based on its proximity to rock layers of known age or fossils of organisms that only existed on Earth for...
This question is asked with the intention of understanding basically the decay constant of radiometric dating (although I know the above is not an entirely accurate representation). If there is a group of radioisotopes whose eventual decay ...
2. We now know the age of the glaciation accurately from radiometric dating of the carbon-14 in logs buried in the drift. 我们现在通过测量掩埋在漂流物中木头放射性的碳-14元素,以精确地确定冰川作用的时期。 youdao 3. The radiometric age of pitchblende is 109-108 m. 沥青铀矿的同位素年龄为108...
The validity of the ionium dates based on U-richsamples is demonstrated by the concordance between 234U/238U and 230Th/234U evolution in time, and by the o activity ratios that are generally within the range of sea-water value of 1.14 ± 0.04 . Some dolomite-rich samples are exceptional ...
Our new field mapping, geochemical investigations, and radiometric dating lead to a re-evaluation of previous suggested models of the massif. The Kazda± metamorphic succession is subdivided into two major units separated by a pronounced unconformity. The lower unit (the Tozlu metaophiolite) is a ...