Topic
The dating of rocks from the abundance of radioactive isotopes they contain, used to establish when crust formed, melted or was reworked.
Researchers dated Oklahoma's Ames crater to 370 million years ago, 97 million years after the Ordovician impacts it was grouped with. That is about 2 million years after the Late Devonian extinction began, though the authors say the impact did not cause it.
Reality
Istanbul Technical University-led geologists date a previously unrecognized magmatic arc in northwestern Iran to about 101-97 million years ago. The Geoscience Frontiers study gives reconstructions of how the Neo-Tethys Ocean closed a dated subduction episode that earlier accounts of the region had missed.
Reality
UT Austin geologists dated zircons from Oklahoma's Ames crater to about 370 million years ago, nearly 100 million years younger than believed. That pulls the buried crater out of the Ordovician impact cluster some researchers cited as evidence of a debris ring around the ancient Earth.
Reality
Berkeley and Padua researchers dated eight Vesuvius sanidine samples to 1,938 years, give or take 13, against the 1,946 years that Pliny's account implies. The same historical date helped make potassium-40's half-life, the constant under every argon-argon age, twice as precise.
Reality
UT Austin researchers dated shocked zircons from Oklahoma's Ames crater to about 370 million years ago, nearly 100 million years younger than believed. That takes Ames out of the Ordovician impact cluster behind the idea of a debris ring around Earth.
Reality
A global compilation of granite ages traces Gondwanan crust from India through most of China into Kazakhstan, and that buried land is what carries the supercontinent past a 75 percent cutoff one of the paper's coauthors calls arbitrary.
Reality
Berkeley and Padua geochronologists dated eight crystals from Vesuvius to 1,938 years, plus or minus 13, against a recorded age of 1,946 years. The same eruption date let them measure potassium-40's decay twice as precisely. Carbon-14 and uranium-lead results can now be checked against that constant.
Reality