Researchers find unexpectedly large methane source in overlooked landscape
When Katey Walter Anthony heard rumors of methane, a potent greenhouse gas, ballooning under the lawns of fellow Fairbanks residents, she nearly didn't believe it.
When Katey Walter Anthony heard rumors of methane, a potent greenhouse gas, ballooning under the lawns of fellow Fairbanks residents, she nearly didn't believe it.
Earth Sciences
Aug 8, 2024
0
235
Mammoths, the massive pre-historic ice age cousins of the modern-day elephant, have always been understood to have inhabited parts of British Columbia, but the question of when has always been a bit woolly.
Paleontology & Fossils
Aug 8, 2024
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71
Rocks recently exposed to the sky after being covered with prehistoric ice show that tropical glaciers have shrunk to their smallest size in more than 11,700 years, revealing the tropics have already warmed past limits last ...
Earth Sciences
Aug 1, 2024
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1693
Nestled high in the Eastern Lesotho Highlands, scientists have uncovered fascinating evidence of an ancient mountain lake that flourished thousands of years ago. This discovery, made by Professor Jennifer Fitchett from the ...
Earth Sciences
Jul 24, 2024
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8
Cut marks on fossils could be evidence of humans exploiting large mammals in Argentina more than 20,000 years ago, according to a study published July 17, 2024 in the open-access journal PLOS ONE by Mariano Del Papa of National ...
Paleontology & Fossils
Jul 17, 2024
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466
Archaeologists have uncovered one of the earliest Christian buildings in the Arabian Gulf—the first physical evidence of a long-lost community.
Archaeology
Jul 12, 2024
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158
We often hear that Aboriginal peoples have been in Australia for 65,000 years, "the oldest living cultures in the world." But what does this mean, given all living peoples on Earth have an ancestry that goes back into the ...
Archaeology
Jul 6, 2024
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22
Scientists in South Africa have been stunned to discover that termite mounds that are still inhabited in an arid region of the country are more than 30,000 years old, meaning they are the oldest known active termite hills.
Plants & Animals
Jul 4, 2024
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25
Historic shipwrecks often evoke dreams of sunken riches waiting on the bottom of the ocean to be reclaimed.
Archaeology
Jun 26, 2024
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113
Archaeologists have been investigating human bones found near the ruins of a bridge in the Three Lakes region of Switzerland. They seek not only to discover what took place, but also to better understand the Celtic heritage ...
Archaeology
Jun 17, 2024
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80
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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