VOLCANO MADNESS: Re: [Geology2] KT Comments

Thursday, April 4, 2013

Re: [Geology2] KT Comments

I'm not sure what our K-T (sorry, I'm stuck in the marl with that one nomer) boundary here in Tennessee possesses. That was something I was remiss with the use of our microscopes at Coon Creek, as I was madly in love and had little sense for anything else during the latter part of my work there. I do know that we found fish scales, fish bones, foraminifera and other small inverts, and other detritus in what we did sample.

However, the exposure of that Iridium layer is easier found outside of Coon Creek, due to the fluctuations caused by the Mississippi Embayment. I do know that it is a dark layer sandwiched between the marl that repels water and the McNairy Sand formation that is so red it screams Fe. And getting to that layer requires a trip through creeks where most people don't want to walk or swim thanks to a nefarious fear of snakes (I don't have that-in fact, I'll chase them). I have found that layer in various places throughout McNairy County, but always near a deep ditch where water is present.

I will go back down there to gain some samples, so Kim won't have to buy it. Besides, West Tennessee is closer to the impact site, overall, and I would like to get a piece of that shiny substance under a scope and see what it really does contain. Excited? You bet. Just wish I had some of you with me to enjoy the find.

Lin

On Thu, Apr 4, 2013 at 11:04 AM, MEM <mstreman53@yahoo.com> wrote:

So much for "trimming" -- it is a bear in the digest mode to correct: here is a response in blanc to the KT issues of yesterday.

Bre Wrote:

Pardon my ignorance, I keep read that there hasn't been any dinosaur fossils found in the impact layer, fossils have only been found below the iridium layer, but nothing in it and that it is an extremely small layer. If it caused the dinosaur extinction why no fossils?

Eman: I believe there was a recent report of duckbilled populations dated up to either 10k or 100k after the K-Pg ( Formerly the K-T Event since we did away with the Tertiary in favor of Paleogene--I prefer K-T and apparently that is still acceptable but I digress) It wasn't just the impact itself as the entire upsetting of the eco system collectively caused the death of the very last dinosaur even those whose ancestors did survive in rare niches until those too were caught up in the inevitable environmental change.

The overall populations of land and marine species had been in decline for some time leading up to the K-Pg event. We also believe we've located several very closely spaced other major impacts around the globe so a decline in all life shouldn't come as a surprise.
Much can be read here
<http://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_boundary>
and here:<http://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_extinction_event>

2e
Kim Wrote:
I cannot overstate or overemphasize how much it would mean to me to have a
large vial or small jar of the K/T Boundary soot.

Eman: Samples are on Ebay all the time plus there are oodles of exposures in Colorado --Check out the Colorado Geological Survey website. The K-Pg boundry material from the Domminican Republic also have small tectites. For some reason the northern Colorado exposures are thick and well preserved--very sooty and I believe also contain lots of fulerenes ( aka Bucky Balls)

2g
Clay Wrote

Wed Apr 3, 2013 12:27 am (PDT) . Posted by:

"Clay Chesney" fossrme

In one of his books Robert Bakker dismissed the impact as the cause of the great extinction and asked, ". . .where are the piles of dinosaur bones? .

EMAN: They exist but were consolidated in unexpected places. A geologist friend of mine, Matt Morgan, was documenting piles of dinosaur bones left high "up slope" in North Dakota apparently deposited there way above normal sea level by any of several tsunami surges from the K-Pg event. Essentially, the tsunami swept up the populations of land based dinosaurs living at the edge of the great inland sea which occupied the interior of North America at the time. We tend to forget that dinosaur skeletons are rare --in general-- outside ash falls, river whirl pool deposits and marl beds. The first dinosaur skeleton found in the US was found in a marl bed in New Jersey. I think this pattern is insightful as to why dinosaur skeletons are not more common.

Clay: snip the wholesale slaughter of millions of bison, most left on the ground after being stripped of their hides, yet now there is scarcely a trace left of those animals.

EMAN: Actually these bones were gathered up into huge piles and railroaded to Chicago to be ground into fertilizer. Google Bison /Buffalo Bone Fertilizer industry.

Eman