Stuck on mass extinction theory...

i am currently researching an assignment about the mass extinction that occurred 65 millions years ago on the KT boundary (the period that the dinosaurs became extinct), in which a terrerstrial object struck the earth in the Gulf of Mexico.

This mass extinction was initiated by an impact located in the Gulf of Mexico named the Chicxulub Crater which is 180km wide created by an impact of an asteroid 10km in diameter travelling at 30km/s.

What is proposed it that this impact in the order of 100,000 mega tons of TNT or more than the worlds supply of nuclear weaponary hit the surface with such a force that it caused volcanic activitiy 180 degrees on the axis of the earth.

Deccan Traps, the area 180 degrees opposite the Gulf of Mexico 65 mya had a period of approx 1 millions years where spontaneous volcanic eruptions occured spewing unknown quantities of debris into the atmosphere and therefore in this researchers opinion was the cause of the mass extinction.

I would like to know the opinion of the experts out there if they believe this bullet theory could occur, and what would account for the extinction of the dinosaurs, if it was a direct result of volcanism? the impact itself? global climate change? or a combination of these occurances, or something different entirely?

For further reading about the bullet theory and ideas about mass extinctions, impacts on other planets and plans for the future check out the writing of Dr Michael Martin-Smith

abob.libs.uga.edu...

I believe the dinosaurs got extinct because of a series of cataclysms. It started with the increased volcanic activity. Then India had a period of volcanic eruptions named bassault lava eruptions which are much more violent than normal eruptions. Too finish it off 2 meteorietes impacted. One at Yucatan and one in India.

My sources? Several programs at the discovery channel.

First of all impact energy of ~10 km sized objects is in scale of world's nuclear stockpile multiplied with thousands.

Originally posted by tomcat ha
Then India had a period of volcanic eruptions named bassault lava eruptions which are much more violent than normal eruptions.

Completely wrong, this kind eruptions aren't violent, only big in them is amount of spewed out stuff. They're like Hawaiian eruptions. And there was no any second impact on India.

Also "end products" of explosive eruptions differ greatly from calm nonviolent Hawaiian eruptions which spew out magma. (instead of fine crushed rock aka volcanic ash)

A possible link between impacts and volcanism became evident in 1974 when the Mariner 10 spacecraft flew past the innermost planet Mercury. The planet was found to be covered with impact craters like the moon. One giant impact crater on Mercury was particularly interesting. Directly opposite the impact point, on the other side of the planet (called the "antipodal point") was a region of highly disrupted terrain with no evidence of an impact. The shock waves from the impact on one side of Mercury had traveled around the surface and met simultaneously at the antipodal point to create the chaotic features. Similar features have since been detected on several moons of the giant planets.

Chicxulub impact and that the shock waves caused the Deccan Traps. Taking into account millions of years of continental drift, this region would have been at the antipodal point to Mexico at the time of the impact.
www.space.com...

Mars has also highland in antipodal point of Hellas impact basin, this highland looks really like it would be result from massive volcanic eruptions.
(~ 40N, 280E right from typical shield volcanoes... and finding Hellas shouldn't be hard)

Really big TIFF-image here.

E_T.... When the huge earthquake hit on Dec 26th there were a number of volcanic eruptions that followed. Would it be unreasonable to assume that this giant impact could have done the same?

When I read Not By Fire But By Ice it states in the book that when there was drilling in the Gulf in that region that volcanic rock was discovered indicating that the crater may have been left by a massive underwater volcanic eruption instead of an impact. Its possible that the data from the drilling may have been misinterpreted. What are your thoughts?

Definitely, but instead of Deccan trap being separate/preceding event it's much more propable that it was just consequence of impact.

Originally posted by Indy..Not By Fire But By Ice it states in the book that when there was drilling in the Gulf in that region that volcanic rock was discovered indicating that the crater may have been left by a massive underwater volcanic eruption instead of an impact. Its possible that the data from the drilling may have been misinterpreted.

How about starting from the fact writer of that book has architect's education?
(and I wouldn't trust them even in building of house)

And he seems to be little late...
Found impact craters were kept always as volcanic craters in the past (~40 years ago), just like Finland's biggest/first found crater Lake Lappajärvi.
Also lot of people said cosmic impacts haven't happened after the birth period of solar system until comet Shoemaker-Levy 9 carpet bombed Jupiter creating earth sized fireballs/"mushroom clouds".

Impact craters leave very specific signs to rocks/bedrock, some of them are caused by extremely fast and hard shock. (effect which can not be fully imitated even in nuclear tests)
Some of the common signs are shatter cones, shocked quartz/planar deformation features (crystal structure look like pages of book dropped to floor at its corner), impact melt, impact breccia.
Impact melt is rock which has been partially/fully melted by shock like name suggest, part of this melted rock is blown "to sky" but lot of it is left on the floor of crater where it along with impact breccia creates impact melt/breccia lens.

Here's excellent diagram of impact crater.
www.lpi.usra.edu...


www.agu.org...
www.scn.org...
www.absoluteastronomy.com...


www.daviddarling.info...
www.impact-structures.com...



Here's information for literature discussing impacts.
www.geophysics.helsinki.fi...

BTW, on surface shatter cones are the most visible sign of impact... after circular depression/formation.
So watch out for them, you might even find new crater.