Pottery was largely unknown in Australia before the recent past, despite well-known pottery traditions in nearby Papua New Guinea and the islands of the western Pacific. The absence of ancient Indigenous pottery in Australia ...
Archaeology
Apr 14, 2024
0
128
A research group coordinated by the University of Helsinki was able to measure a spike in radiocarbon concentration of trees in Lapland that occurred after the Carrington flare. This discovery helps to prepare for dangerous ...
Planetary Sciences
Apr 4, 2024
0
51
The Greater Caucasus mountain range stretches between the Black and Caspian Seas across parts of Russia, Georgia, and Azerbaijan. These formidable peaks are the result of the subduction of the Arabian plate beneath the Eurasian ...
Earth Sciences
Mar 27, 2024
0
1
Among the vast expanse of Antarctica lies the Thwaites Glacier, the world's widest glacier measuring about 80 miles on the western edge of the continent. Despite its size, the massive landform is losing about 50 billion tons ...
Earth Sciences
Feb 26, 2024
0
664
Two University of Wyoming anthropology professors have discovered one of the earliest circular plazas in Andean South America, showcasing monumental megalithic architecture, which refers to construction that uses large stones ...
Archaeology
Feb 14, 2024
0
150
Pioneering groups of humans braved icy conditions to settle in northern Europe more than 45,000 years ago, a "huge surprise" that means they could have lived there alongside Neanderthals, scientists said Wednesday.
Archaeology
Feb 4, 2024
0
51
River flooding is among the most catastrophic disasters worldwide. The Pearl River, the longest watercourse in southern China, particularly its lower reach with dense population and economic activity, has been identified ...
Earth Sciences
Jan 25, 2024
0
4
Excavation at the dried-out lake site of Papowo Biskupie in north-central Poland has revealed more than 550 bronze artifacts, providing the most telling evidence of ritual deposition of metal by the occupants of the region ...
Archaeology
Jan 24, 2024
0
335
A new study from a University of Colorado Boulder researcher, conducted with colleagues in Argentina, sheds new light on how the introduction of horses in South America led to rapid economic and social transformation in the ...
Archaeology
Dec 24, 2023
0
133
Timing is crucial when it comes to understanding the origins of humanity. Developing better dating techniques to discover the ages of key fossils will help scientists to discover how Homo sapiens and our relatives evolved.
Evolution
Dec 19, 2023
0
1286
Carbon-14, 14C, or radiocarbon, is a radioactive isotope of carbon discovered on February 27, 1940, by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley, though its existence had been suggested already in 1934 by Franz Kurie. Its nucleus contains 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method to date archaeological, geological, and hydrogeological samples.
There are three naturally occurring isotopes of carbon on Earth: 99% of the carbon is carbon-12, 1% is carbon-13, and carbon-14 occurs in trace amounts, e.g. making up as much as 1 part per trillion (0.0000000001%) of the carbon in the atmosphere. The half-life of carbon-14 is 5,730±40 years. It decays into nitrogen-14 through beta decay. The activity of the modern radiocarbon standard is about 14 disintegrations per minute (dpm) per gram carbon.
The atomic mass of carbon-14 is about 14.003241 amu. The different isotopes of carbon do not differ appreciably in their chemical properties. This is used in chemical research in a technique called carbon labeling: some carbon-12 atoms of a given compound are replaced with carbon-14 atoms (or some carbon-13 atoms) in order to trace them along chemical reactions involving the given compound.
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