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- The extinction event 359 mya that ended Devonian times may have been caused by a nearby supernova.
A popular science article on the end of the Devonian era examines the likelihood of an extinction event mediated by a nearby supernova.
https://www.sciencedaily.com/releases/2020/08/200818142104.htm
Per the article -
A convincing argument can be made by finding Samarium 146 and/or Plutonium 244 isotopes in rock strata from that period.
The proposed model includes what the authors call a double whammy:
First a blast of ionizing radiation, then a massive radioactive cloud of ejecta that persists over a long period. Both which could alter the magnetosphere of Earth and allow the solar wind to damage extant flora and fauna. The latter cloud effect could persist over long periods. Which matches the known geologic record of a ~100000 year decline in species diversity at the end of the Devonian.
My takeaway is this looks like a great research project.
Gather rocks from several sites around the globe, test for those two isotopes that do not naturally occur on Earth. The most likely results will be either clearly negative or positive if the experiment is well designed. A positive result is sure to spark intense criticism of the experimental design. New findings are often generate that. The downside is Geology has a long and tortuous history of downright ugly debate.
Ruling out other causes for the presence of those two isotopes would be intense. Meteors.
Finding anomalous abundances of weird elements in rock layers often is the result of meteor impacts. They may need to be ruled out. Meteor impacts can create layers. Thin layers with odd isotopes or elements have been found and used to help prove other hypotheses. Example:
Iridium in the K-Pg (KT is the old name) boundary layer caused by the Chicxulub impact, which made life hard for the dinosaurs. This layer is high in Iridium, rare or non-existent in most Earth rock. It is sometimes called the Iridium Anomaly.
https://en.wikipedia.org/wiki/Cretaceous–Paleogene_boundary
https://en.wikipedia.org/wiki/Chicxulub_crater
https://en.wikipedia.org/wiki/Iridium_anomaly
https://www.sciencedaily.com/releases/2020/08/200818142104.htm
Per the article -
A convincing argument can be made by finding Samarium 146 and/or Plutonium 244 isotopes in rock strata from that period.
The proposed model includes what the authors call a double whammy:
First a blast of ionizing radiation, then a massive radioactive cloud of ejecta that persists over a long period. Both which could alter the magnetosphere of Earth and allow the solar wind to damage extant flora and fauna. The latter cloud effect could persist over long periods. Which matches the known geologic record of a ~100000 year decline in species diversity at the end of the Devonian.
My takeaway is this looks like a great research project.
Gather rocks from several sites around the globe, test for those two isotopes that do not naturally occur on Earth. The most likely results will be either clearly negative or positive if the experiment is well designed. A positive result is sure to spark intense criticism of the experimental design. New findings are often generate that. The downside is Geology has a long and tortuous history of downright ugly debate.
Ruling out other causes for the presence of those two isotopes would be intense. Meteors.
Finding anomalous abundances of weird elements in rock layers often is the result of meteor impacts. They may need to be ruled out. Meteor impacts can create layers. Thin layers with odd isotopes or elements have been found and used to help prove other hypotheses. Example:
Iridium in the K-Pg (KT is the old name) boundary layer caused by the Chicxulub impact, which made life hard for the dinosaurs. This layer is high in Iridium, rare or non-existent in most Earth rock. It is sometimes called the Iridium Anomaly.
https://en.wikipedia.org/wiki/Cretaceous–Paleogene_boundary
https://en.wikipedia.org/wiki/Chicxulub_crater
https://en.wikipedia.org/wiki/Iridium_anomaly