Vorkosigan

<a href="http://www.ev1.net/english/news/newsarticle.asp?articleID=21609126&subject=science " target="_blank">here</a>

lpetrich

This reminds me that I have to get to work on a project I'd neglected for the last month or so -- a globe viewer that can read in image files and project them appropriately. The purpose is to display past continent positions, so I can visualize continental drift.

This could be used to find out where an asteroid would have struck, if the Siberian Traps had been an antipodal effect of that asteroid. The Moon and Mercury have some examples of jumbled, chaotic terrain on the other side from some big craters, and the same effect could have happened on the Earth.

For the Permo-Triassic extinction, the asteroid would have hit a little to the west of the southern end of South America, which was a part of Gondwana at that time. That area of crust would have become subducted as South America drifted westward, erasing the asteroid's crater.

And for the Cretaceous-Tertiary extinction, the Chicxulub crater's antipode is somewhat to the east of India, which had had its Deccan Traps eruptions at the same time; the latitude is correct, but the longitude is a bit off.

As to the nature of the eruptions themselves, these were likely Hawaii-style eruptions, which produce relatively fluid lava and relatively little volcanic ash. However, they would also release CO2 and SO2. Carbon dioxide is a greenhouse gas, while sulfur dioxide forms sulfuric-acid droplets, making the atmosphere more reflective -- effects that go in opposite directions.

Here's a <a href="http://www.scotese.com" target="_blank">nice site</a> showing some reconstructed continental drift.