GIFT2011: The delicate balance between Chicxulub impact and/or Deccan traps
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- čas přidán 10. 07. 2012
- GIFT presentation by Jan Smit (full title: The delicate balance between Chicxulub impact and/or Deccan traps induced mass-extinctions at the K-Pg boundary) at the 2011 General Assembly of the European Geosciences Union. The 2011 Workshop, webtv.egu.eu/gift/2011/, covered Evolution and Biodiversity. (Credit: EGU/Cactus)
The EGU Committee on Education has organized Geosciences Information For Teachers (GIFT) Workshops since 2003. These are two-and-a-half-day teacher enhancement workshops held in conjunction with EGU's annual General Assembly. There, selected top-level scientists working in the Earth Sciences offer the invited teachers talks centered on a different theme every year.
The main objective of the GIFT workshops is to spread first-hand scientific information to science teachers of primary and secondary schools, significantly shortening the time between discovery and textbook, and to provide the teachers with material that can be directly transported to the classroom. In addition, the full immersion of science teachers in a truly scientific context (EGU General Assemblies) and the direct contact with world leader geoscientists are expected to stimulate curiosity towards scientific research that the teachers then transmit to their pupils. - Věda a technologie
At 31.33 he shows a dinosaur tooth and dinosaur vertebra mixed in with the debris .The dinosaurs they came from might well have witnessed the asteroid itself coming down and the entire event.A truly unique fossil find.Actual Eyewitnesses!
best lecture I have heard about KTB
a thorough and convincing lecture in favor of Chicxulub
Very compelling presentation. Why have we not heard more about the vertebrate fossils in the presumed tsunamite? I'm still unsure of the argument for placing the "Z" coal lower in the Hell Creek: I thought the "boundary" was where the clay layer and the tektites occur - yet no mention of them occurring in the "Z" coal to confirm the impact layer? Also, with regard to cooling, there is a sea level drop prior to the K-T boundary - so cooling was not "sudden". As for the Deccan traps, people are not understanding their full potential for environmental impact. Last year Kilauea erupted and extruded a river of lava that emitted all sorts of noxious gases. People were astounded at all the smoke and fire - yet it was a pinpoint compared to what happened during the Deccan eruptions - and the Deccan eruptions lasted hundreds of thousands of years! Surely that continual assault on the planet did in many more organisms on the planet than just the inoceramid clams.
I have no doubt that Chicxulub impact was spectacular, but I would like to have heard more about the Deccan Traps. Apparently they amounted to an eruption of 5e+5-1.5e+6 km^3 of lava, with most of it being erupted within 30k years. That surely had some adverse impact on life at the time. Also, it seems that the dates for impacts, eruptions, extinctions, etc, are not well constrained. It's common to see dates given +-300k years. In geologic time, a blink of an eye, but quite meaningful for life.
www.theatlantic.com/magazine/archive/2018/09/dinosaur-extinction-debate/565769/
czcams.com/video/og_Zues7w3w/video.html
It looks like the climate data favors Chicxulub but it is skewed by Chicxulub as an outlier after Deccan released most of the SO2.
Are the dates of the impact and the flood basalt event in India really "certain"?
Layered rocks of the ecretionary lapilli seem like hail, continual surges of hot air will force the small particals to form another layer everytime it is recycled through the layering process due to updrafts into cooler air, until they become heavier than the updrafts force can handle and fall.
And the fossils have been preserved due to their covering of the sediments from those rivers, indicating that they were there after the river formed. Plus your decision to indicate that tha z-coal line is inducative of the k/t boundary, even though every other part of earth is using iridium to indicate that bounary fits your ideals, but not science.
sir i stared phd in doing research in deccan traps in india, which site is suitable for doing research in indian deccan volcanism, give suggestion, thnak you
Where is the rest of the lecture?
It seems unlikely to me that randomly a large volcanic eruption happened at the same time as a large asteroid impact (but maybe I'm wrong that this is improbable). I wonder whether or not the Deccan Traps might have been caused by a much larger asteroid impact and the Chicxulub impact was merely a secondary impact caused by debris from the original???
I'm not making any kind of argument here rather simply hypothesizing--has this idea been refuted (and/or can it be refuted)?
The Deccan Traps were a series of ultra massive eruptions that occurred over many thousands of years, ~65 million years ago.
See Dr. Chatterjee’s many papers about a possible super giant impact structure off the coast of India, called Shiva.
there is a theory that an asteroid struck off the coast of India near KTB
Error bars
Why do none of the craters on earth have the rock that created them? Always totally vaporized ... really?
that is not unusual. Unlike the moon and other places that don't have the mechanisms that exist on earth: eg, erosion from water & wind, tectonic plates moving around, changing sea levels, continental drifts, etc. Mainly it's because of the erosion of the terrain over geologic time spans. The fact that this giant crater was found under the water, at the Yucatan Peninsula (Chicxulub) is not a typical thing. Billions of years ago there was a time, when the earth was young, when it went through a long period when it was getting bombarded on a quite frequent basis. But, unlike the moon, for example, all those impact scars were erased & replaced by new land, changed topography of the land, sea level differences, etc.
Why do you think a rock traveling at over 20km/sec would still be intact after impact?
Iron-nickel asteroids leave debris behind. The energy of large impacts just leaves gaseous debris at a few thousand degrees orbiting the earth.
Yes, the enormous speed at which the meteor hits earth will reduce it to vapors.This has been tested in labs