On Thu, 06 Apr 2006 06:50:36 -0400, "IrquiM" wrote:

|David J Bush skrev:
| It is a bit suspicious that Iceland also happens to sit on or near
| the mid-Atlantic rift, but who knows...?
|
|Suspicious?
|
|Logical I'd say!

Since the currently held view is that Iceland originated purely as a
result of volcanic activity, I would imagine that most geologists
would regard an impact origin theory as an unjustified complication.
If a random object strikes the Earth, it is more likely to miss
than hit a border between large tectonic plates. That's all I meant,
when I said it was suspiscious.

But just because it is unlikely doesn't mean it couldn't have happened.
In his article, Ley describes what might happen if an object large
enough punched a hole through the ocean and the Earth's crust. The
ocean would rush in and be turned to steam by the upwelling magma.
A huge amount of water would be pumped into the atmosphere, along with
all the dust from the explosion. The increased cloud cover might
contribute to an overall cooling of the Earth's climate, possibly
even a relatively sudden ice age. You've heard all this before, but
Willy Ley described it first.
..