Hi all, In regard to Tunguska and bioturbation.
Paul H's post on bioturbation brings up an interesting question. The first expedition led by Leonid Kulik to Tunguska in 1927 to study the devastation and search for meteorites happened 19 years AFTER the event in 1908, (He had an earlier expedition in 1921 but wasn't successful in reaching the epicenter until 1927).
19 years is a LONG time for meteorites in the forested and swampy environment full of little critters, insects, and plants that could bury any stones. How deep can meteorites be buried in 19 years of snow, rain storms, mudslides, spring melt, critters, ants, termites, and other animals?
Could bioturbation be one cause for the failed attempts to recover meteorites at Tunguska?
You also have to take into account Leonid Kulik's mindset at the time. He was thinking that meteorites would be directly beneath the blast at the epicenter. Which made sense. Would he be looking for meteorites 10-40 miles away from the epicenter? He attributed the circular swampy bogs to craters formed by the meteorite impacts, which unfortunately turned out to be incorrect. Did he search for meteorites only under the epicenter? How far from the epicenter did his search area expand?
Were there other expeditions to Tunguska to search in the 10-40 mile ring from the epicenter?
Most scientists believe that the sheer force and energy of the blast at Tunguska event vaporized every trace of the meteoroid explaining that this is why there are no fragments to be recovered. This obviously makes sense, but would EVERYTHING be vaporized?
Take a look at the "accepted" theory of Chixulub and the extinction of the dinosaurs. This widely accepted theory is now being challenged. Perhaps we should look at Tunguska again, in a new light.
I am just wondering something out loud here about the Tunguska event. Yesterday I sent a load of links and questions and surprisingly got no response. Come on, this is the largest meteorite related blast in recent recorded history. So I'll will ask again.
Is it possible that there are in fact meteorites that survived the Tunguska event by being blasted away much further from the epicenter than previously thought?
Below is a copy of my post about some questions I had on Tunguska in yesterday's post.
-----------------------ORIGINAL POST--------------------- Hi Listees, Recently there's been more interest in the Tunguska event. More scientists are trying to explain it, and some are even looking at a lake near the blasts epicenter believing that this is the missing crater. http://news.bbc.co.uk/2/hi/science/nature/6239334.stm Photo of Lake Cheko: http://a52.g.akamaitech.net/f/52/827/1d/www.space.com/images/070626_lake_cheko_02.jpg A witness in Vanovara (36 Miles SE of the epicenter) said in O. Richard Norton's "Rocks From Space" "The crash was followed by noise like stones falling from the sky, or guns firing." and "when I lay on the ground I covered my head because I was afraid that stones might hit it." We all know too well that witness reports aren't ideal information but useful anyway. But, how would this person know to say that there was a "noise like stones falling" unless that were the case? Or did the witnesses report become tainted after countless interviews? How many times was this witness interviewed? I know people have searched for meteorites under and around the epicenter area. But what if this was a stony meteoroid, and the explosion blasted meteorite pieces 30-50 miles away. The devastation this explosion caused is evidence that it was one hell of a blast and was on par with a nuclear explosion. YouTube Video: http://www.youtube.com/watch?v=EiXpp-i442s Donald Yoemans (JPL) states in the History Channel video that this blast was 15 megatons of equivalent energy "roughly 1000 times that of the Hiroshima blast." VERY COOL ARTIST RENDERING: http://svidea.us/misha/image/tunguska2.jpg Photos of Devastation: http://astro.wsu.edu/worthey/astro/html/im-meteor/tunguska-photo.jpg http://upload.wikimedia.org/wikipedia/commons/a/ad/Tunguska.png http://www.wilsonsalmanac.com/images1/tunguska3.jpg http://www.world-mysteries.com/sci_tu3.gif Artist Rendering: http://aura.gaia.com/photos/34/338910/large/tunguska-1.jpg Area Map: http://www.world-mysteries.com/sci_tunguska1.gif Blast Damage Area: http://www.world-mysteries.com/sci_tu2.gif When you factor in all this information, how come people aren't looking 30-40 miles away for debris from this blast. If it was as powerful as they say (as evidenced by the downed trees and other devastation) wouldn't it make perfect sense that area around the blast would be completely void of meteorites as is the case? Having said that, wouldn't it be prudent to look further away from the blasts epicenter for fragments? How far will a blast such as that throw debris? If a Navy destroyer can launch a huge shell a hundred miles using a few pounds of gunpowder, how far can a meteoroid blast such as this launch stone fragments? Bomb squad techs and investigators will be the first to tell you that there's always something left over from a blast no matter how powerful. Pieces get thrown sometimes miles from the epicenter of powerful blast. In the case of Tunguska this blast was nuclear powerful! Yes a lot of the mass would have been melted and disintegrated but, how likely is it really that the blast would make ALL trace of the meteoroid disappear? Could there be meteorite pieces within a 30-50 mile ring around the epicenter? -- Regards, Eric Wichman Meteorites USA http://www.meteoritesusa.com 904-236-5394 ______________________________________________ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
