[meteorite-list] Another, Different Chicxulub Theory

[Sterling K. Webb]

Dear List,
 
"Scientists Say Dinosaur-Killing 
Asteroid Made Earth's Surface 
Act Like Liquid:"
http://www.npr.org/sections/thetwo-way/2016/11/22/503013290/scientists-say-d
inosaur-killing-asteroid-made-earths-surface-act-like-liquid
 
"...recently published in the journal 
"Science." Deep drilled samples from
the crater... settled a major debate 
about how a planet's surface behaves 
during an asteroid impact - and 
how the mountain ring, known as 
a "peak ring," is formed. Some 
researchers have argued that the 
process is dominated by melting 
on the surface, which would mean 
that the ring is mainly formed from
material moving from side-to-side. 

In that model this ring of peaks are 
created by shallow material kind 
of moving towards the center and 
being uplifted. "On the drill floor 
when we're out there, out in our 
hard hats and so on, looking at 
these cores coming up," the 
researchers were seeing pink 
granite that emerged from about 
6 miles deep in the Earth and 
not the limestone that would 
have been on the surface during 
the Cretaceous Period... Everybody 
staring at it went, 'Wow, there's the 
answer. It's from deep.' "

The researcher was Sean Gulick, 
a geophysicist at the University 
of Texas, Austin. Gulick helped 
lead a team of researchers that 
drilled for samples of that mountain 
ring in the Chicxulub crater off 
the coast of Mexico.


Sterling K. Webb