[SunkenCiv]

Much longer ago -- 2.2 million years -- the Eltanin impact happened, and left telltale iridium. Couldn't find the file about the iridium layer, but it came from the web anyway.

Two Catastrophe Scenarios
by William Corliss

About 2.2 million years ago, a chunk of space debris about a kilometer in diameter splashed down in the Bellingshausen Sea between Antarctica and South America. It was some splash! The splash zone was about 20 kilometers across, waves 4 kilometers high raced away from Ground Zero, and a column of salt water ascended miles high into the upper atmosphere. The TNT equivalent is estimated at 12 billion tons. Ice clouds formed and shaded the planet, causing severe climate changes. On the floor of the Bellingshausen Sea, 5 kilometers deep, lies the Eltanin Impact Structure.

[Fred Nerks]

About 2.2 million years ago, a chunk of space debris about a kilometer in diameter splashed down in the Bellingshausen Sea between Antarctica and South America. It was some splash! ...

Sure was!