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★★南極の氷の下に巨大クレーター発見★★

1 :同定不能さん:2006/06/06(火) 12:37:25
ネイチャー・ニュースより

南極の氷の下に巨大クレーター発見!か?
恐竜を絶滅させたユカタン半島沖クレーターの、実に4〜5倍の巨大な
クレーターがある!とオハイオ州立大のRalf von Freseが発表。
大規模火山活動によるとされてる、250万年前の二畳紀ー三畳紀境界大絶滅が
実は、このクレーターを作った天体衝突イベントによるのでは?と主張。
ネイチャニュース↓ちょと引用しまっす
ttp://www.nature.com/news/2006/060529/full/060529-11.html
"Does a giant crater lie beneath the Antarctic ice?"
The first sign of this possible impact was spotted by NASA's GRACE
satellites, a pair of orbiting probes that sense slight variations
in the Earth's gravity field. They revealed a 320-kilometre-wide plug
of dense mantle material more than 1.6 kilometres beneath the East Antarctic
ice sheet in an area known as Wilkes Land.・・・
When they looked at airborne radar images of the area, they found what they
say looks like a crater — a circular ridge some 500 kilometres wide running
around the mascon. "It could be the biggest impact ever found on Earth," says von Frese.・・
If an incoming asteroid did gouge out the hole it must have been up to 50 kilometres across,
says von Frese. That's four or five times larger than the object thought to have created
the Chicxulub crater on the Yucatan peninsula in Mexico, which was probably
responsible for wiping out the dinosaurs some 65 million years ago.
But that's peanuts compared with the Permian-Triassic extinction, which destroyed
more than three-quarters of all species on Earth about 250 million years ago.
The cause of this mass extinction is still hotly debated by scientists.・・・
Von Frese notes that the explanations aren't mutually exclusive: the shockwaves
from a huge impact could have travelled through the planet to trigger the
eruptions in Siberia, delivering a devastating combination of disasters

2 :納豆 ◆RIJOsogZOg :2006/06/06(火) 13:05:37
競輪板より記念パピコ

3 :同定不能さん:2006/06/07(水) 14:54:04
不思議の海のナディアで証明済み

4 :同定不能さん:2006/06/08(木) 11:00:43
>>1
250万年前って三畳紀?

5 :同定不能さん:2006/06/08(木) 12:56:15
>>1
2億5千万年前じゃ?

6 :同定不能さん:2006/06/14(水) 07:12:37
グランディスの姐さんと、ぬるぽしたい
ハァハァ

7 :同定不能さん:2006/06/14(水) 11:55:02
ゆかタンのエロ画像はまだですか

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