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  • Around 252 million years ago

  • more than 96 percent of marine

  • species and 70 percent of land

  • species disappeared in a

  • geological instant. This event

  • the so-called end-Permian mass

  • extinction or more commonly

  • known as, "The Great Dying"

  • remains the most severe

  • extinction event in Earth's

  • history, but its direct cause

  • has remained a mystery.

  • Scientists suspect massive

  • volcanic activity in an area of

  • Russia called The Siberian Traps

  • may have had a role in the

  • Great Dying by raising the air

  • and sea temperatures and

  • releasing toxic amounts of

  • greenhouse gases into the

  • atmosphere of a very short

  • period of time. However, until

  • now, scientists could not

  • pinpoint when exactly the mass

  • extinction and eruptions happened

  • in relation to each other.

  • MIT researchers have now

  • determined the Siberian Traps

  • erupted at the right time and

  • for the right duration to have

  • been a likely trigger for the

  • end-Permian extinction.

  • By determining the age of rocks

  • in the region the team came up

  • with an exact timeline for the

  • start and end of the eruptions.

  • They found that the Siberian

  • Traps began to erupt around

  • 300 thousand years before the

  • start of the extinction.

  • These initial eruptions were

  • followed by massive outpourings

  • of lava covering a region as

  • large as the United States. This

  • area likely kept erupting in

  • fits and starts finally petering

  • out about 500 thousand years

  • after the extinction's end.

  • While the Siberian Traps has

  • long been a suspected cause of

  • the end-Permian extinction the

  • team says its new timeline is

  • in essence a smoking gun,

  • placing the eruptions in the

  • right place and time to have

  • been the extinction's main

  • trigger. Next, the team hopes

  • to determine the exact tempo of

  • eruptions, to perhaps identify

  • a tipping point int he planet's

  • climate leading up to the

  • mass extinction.

Around 252 million years ago

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B1 中級 美國腔

西伯利亚陷阱可能引发了二叠纪末期生物大灭绝(Siberian Traps likely triggered end-Permian mass extinction)

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    joey joey 發佈於 2021 年 05 月 15 日
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