Between the two great "Mass Extinction Events" and Serendipity !

[studiot]

These references do you mike?

 

https://www.google.co.uk/images?hl=en-GB&biw=&bih=&q=wignall+siberian+traps&gbv=2&sa=X&oi=image_result_group&ei=rEgiU7L-FsaZ0QX41YGICg&ved=0CEMQsAQ

[Mike Smith Cosmos]

These references do you mike?

 

https://www.google.co.uk/images?hl=en-GB&biw=&bih=&q=wignall+siberian+traps&gbv=2&sa=X&oi=image_result_group&ei=rEgiU7L-FsaZ0QX41YGICg&ved=0CEMQsAQ

 

Fairly comprehensive set of pictures . Ta

 

Mike

[Acme]

Well I think you are right , but there appears to be a bit of a theory about that , an impact by a, or a series of asteroids impacting even on the other side of the earth may have triggered the Siberian traps. I will try and find the quote. I think the thing lasted quite some time , dare I say 1000's even more years . I think .

 

Mike

The graph I posted gives that association, but I neglected to add the link to the full article and can't edit now. Here it is: Asteroid/Comet Impact Craters and Mass Extinctions >> http://users.tpg.com.au/users/tps-seti/crater.html

 

It is not proven yet, but suspected that the Siberian flood deposits may have been triggered by an antipodal impact near Australia. The crater there is called Bedout, as seen on the graph I posted. Here's more on it: >> Bedout: A Possible End-Permian Impact Crater Offshore of Northwestern Australia >> http://www.sciencemag.org/content/304/5676/1469.abstract

 

I don't have permission to access the full article, but here is the Abstract.

The Bedout High, located on the northwestern continental margin of Australia, has emerged as a prime candidate for an end-Permian impact structure. Seismic imaging, gravity data, and the identification of melt rocks and impact breccias from drill cores located on top of Bedout are consistent with the presence of a buried impact crater. The impact breccias contain nearly pure silica glass (SiO2), fractured and shock-melted plagioclases, and spherulitic glass. The distribution of glass and shocked minerals over hundreds of meters of core material implies that a melt sheet is present. Available gravity and seismic data suggest that the Bedout High represents the central uplift of a crater similar in size to Chicxulub. A plagioclase separate from the Lagrange-1 exploration well has an Ar/Ar age of 250.1 ± 4.5 million years. The location, size, and age of the Bedout crater can account for reported occurrences of impact debris in Permian-Triassic boundary sediments worldwide.

Besides impacts causing antipodal volcanic eruptions, impacts may cause eruptions by decompression right where they hit. Here's a PDF on that: IMPACT DECOMPRESSION MELTING: A POSSIBLE TRIGGER FOR IMPACT INDUCED VOLCANISM AND MANTLE HOTSPOTS ?>> http://www.mantleplumes.org/WebDocuments/JonesSpringer2003.pdf

[Mike Smith Cosmos]

The graph I posted gives that association,.....................

 

Well Swedgen lives in Australia . So he can pop out and have a check up !

 

Mike

[Acme]

Well Swedgen lives in Australia . So he can pop out and have a check up !

 

Mike

He'll need a boat. The crater is offshore.

[Mike Smith Cosmos]

He'll need a boat. The crater is offshore.

 

Well I am your man !

 

 

mike [ oops ! copy courtesy Acme ]

Edited March 14, 2014 by Mike Smith Cosmos

[Acme]

Well I am your man !

There is a second Australian impact crater that may have triggered extinctions in late Devonian (364 ± 8 million years ) It's on land. Krike!!

 

Woodleigh crater @ Wiki: >> http://en.wikipedia.org/wiki/Woodleigh_crater

 

Woodleigh is a large meteorite impact crater (astrobleme) in Western Australia, centred on Woodleigh Station east of Shark Bay. A team of four scientists at the Geological Survey of Western Australia and the Australian National University, led by Arthur J. Mory, announced the discovery in the 15 April 2000 issue of Earth and Planetary Science Letters.[1]

 

The crater is not exposed at the surface and therefore its size is uncertain. The original discovery team believe it may be up to 120 km (75 mi) in diameter,[1] but others argue it may be much smaller, with one study suggesting a diameter closer to 60 km (37 mi).[2] The larger estimate of 120 km, if correct, would make this crater tied for the fourth largest confirmed impact structure in the world, and imply a bolide (asteroid or comet) about 56 km (3.13.7 mi) in diameter.[3] A more recent study suggests the crater could be between 60 to 160 km or more, and was produced by a comet or asteroid 6 to 12 km wide.[4]

...

The Woodleigh impact event, originally thought to have occurred between the Late Triassic and Late Permian, is now thought to date from 364 ± 8 million years (Late Devonian).[5] This time corresponds approximately to a minor extinction event when around 40% of species disappeared. There is evidence for other large impact events at around the same time, so if the extinction is related to impact, perhaps more than one crater was involved.. It is on land and called Woodleigh.

...

Ooops... credit Acme

Edited March 14, 2014 by Acme

[Mike Smith Cosmos]

There is a second Australian impact crater that may have triggered extinctions in late Devonian (364 ± 8 million years ) It's on land. Krike!!Woodleigh crater @ Wiki: >> http://en.wikipedia.org/wiki/Woodleigh_crater Ooops... credit Acme

I have come across another major eruption ,akin to a mass extinction event . ... Toba .... Indonesia..Sumatra 75,000 years ago .

 

Although it is 45 mins long ( the video not the eruption) , it is worth watching if you are interested in near , mass extinction events . It is particularly on my mind as in 2 days I make my way to the Canary Islands (8th april 2014. ) I am going to this chain of Islands that got their origin by volcanic plumbs erupting under the ocean and making an island , then the tectonic plate moves the island onward , then another plumb eruption creates a new island and so on. In 1972 an eruption occurred on La Palma , one of the islands. I am going up toward the caldera on Grand Canaria. I have to look at a small native Canarian Fincas which is in the family and going to a daughter.( next to the small village/ town of Fataga See following :-

the town of Fataga is on the right and Fincas ( native house) is in the middle of picture ( courtesy of tar and google earth). . From space ( little white rectangle is looking down on the palm leaves roof and walls footprint.

 

 

 

Tar has asked me to do some phenomenal experiment with 3 meter sides being seen from space. ( maybe I paint the stones white to show up better. ( or lasers ) ? I am going to build a memorial 3 meters long * running SW to NE as two sides of a TARadian two diamond shape . ( in memory of the first users of Diamonds based on TaRadians { Tar, Janus , MD63356, Imatfaal, ACme, ....& mike } [Who says I don't do experiments - ,beat that one ] * [ Radius of Earth 6271000 meters and kept dividing by two until I got to 3.0379 meters.]

Now Seen from across the valley .

Between the palm tree and the small shrub the fincas can be seen strait forward .

Cortesy of trip advisors.

 

l have been commissioned by the Exeter u3a geology group to bring back photos and rocks. Meanwhile I hope a super volcano does not go off while I am here .

 

Sit back and enjoy the video :-

 

Link :- http://m.youtube.com/watch?v=j5jcBWzB3nM

 

Oops ! I better hurry up with these lines for Tar

 

Mike

Edited April 6, 2014 by Mike Smith Cosmos

[Acme]

 

There is a second Australian impact crater that may have triggered extinctions in late Devonian (364 ± 8 million years ) It's on land. Krike!!

 

Woodleigh crater @ Wiki: >> http://en.wikipedia.org/wiki/Woodleigh_crater

I have come across another major eruption ,akin to a mass extinction event . ... Toba .... Indonesia..Sumatra 75,000 years ago .

Although it is 45 mins long ( the video not the eruption) , it is worth watching if you are interested in near , mass extinction events.

 

I've done some reading on Toba, but I don't think I ever checked its antipode for a possible impact site. Currently running short of time and battery so will just give you a handy antipode mapping tool for now. >> http://www.findlatitudeandlongitude.com/antipode-map/#.U0HNFY2PJLM

 

It is particularly on my mind as in 2 days I make my way to the Canary Islands (8th april 2014. ) I am going to this chain of Islands that got their origin by volcanic plumbs erupting under the ocean and making an island , then the tectonic plate moves the island onward , then another plumb eruption creates a new island and so on. In 1972 an eruption occurred on La Palma , one of the islands. I am going up toward the caldera on Grand Canaria. I have to look at a small native Canarian Fincas which is in the family and going to a daughter.( next to the small village/ town of Fataga See following :-

image.jpg the town of Fataga is on the right and Fincas ( native house) is in the middle of picture ( courtesy of tar and google earth). . From space ( little white rectangle is looking down on the palm leaves roof and walls footprint.

 

Now Seen from across the valley .

Between the palm tree and the small shrub the fincas can be seen strait forward . image.jpg

Cortesy of trip advisors.

 

l have been commissioned by the Exeter u3a geology group to bring back photos and rocks. Meanwhile I hope a super volcano does not go off while I am here .

Sit back and enjoy the video :-

Link :- http://m.youtube.com/watch?v=j5jcBWzB3nM

Oops ! I better hurry up with these lines for Tar

 

Mike

IIRC, the East coast of the US is in more danger of loss of life & property than La Palma itself in the event of a quake large enough to shear off a major chunk of island. Can we say tsunami?

Can't wait to hear your report & see your pics. Bon voyage.

[Acme]

I've done some reading on Toba, but I don't think I ever checked its antipode for a possible impact site. Currently running short of time and battery so will just give you a handy antipode mapping tool for now. >> http://www.findlatitudeandlongitude.com/antipode-map/#.U0HNFY2PJLM

...

I was plugged in and time advantaged so I found the antipode to Lake Toba. Mind you I am not suggesting every hotspot or super-volcano has its beginning in an antipodal impact, but as the case is well made for some it behoves us to at least have a look. There is also the possibility Toba is the result of rebound from an impact right where it is, though I've not read anything suggesting that.

 

Not sure if any impact has been suggested off the coast of Ecuador, so I'll poke into that a bit too.

 

I have come across another major eruption ,akin to a mass extinction event . ... Toba .... Indonesia..Sumatra 75,000 years ago .

 

...

Mike

So looking on GoggleEuth, no apparent impact crater off Ecuador. Toba's antipode is right on the subduction plate boundary there so maybe any trace was erased. While 75,000 years seems not long enough to erase impact evidence, geologic study has shown that Toba has been a caldera for ~850,000 years*. Duck & cover!!

 

*source: >>http://en.wikipedia.org/wiki/Lake_Toba

...

IIRC, the East coast of the US is in more danger of loss of life & property than La Palma itself in the event of a quake large enough to shear off a major chunk of island. Can we say tsunami?

Can't wait to hear your report & see your pics. Bon voyage.

It seems this scenario may have been over-hyped. I feel so used.

 

ABSTRACT

Massive flank failures of island stratovolcanoes are extremely rare phenomena and none have occurred within recorded history. Recent numerical modeling studies, forecasting mega tsunami generation from postulated, massive slope failures of Cumbre Vieja in La Palma, Canary Islands, and Kilauea, in Hawaii, have been based on incorrect assumptions of volcanic island slope instability, source dimensions, speed of failure and tsunami coupling mechanisms. Incorrect input parameters and treatment of wave energy propagation and dispersion, have led to overestimates of tsunami far field effects. Inappropriate media attention and publicity to such probabilistic results have created unnecessary anxiety that mega tsunamis may be imminent and may devastate densely populated coastlines at locations distant from the source - in both the Atlantic and Pacific Oceans.

 

The present study examines the assumptions and input parameters used by probabilistic numerical models and evaluates the threat of mega tsunami generation from flank failures of island stratovolcanoes. Based on geologic evidence and historic events, it concludes that massive flank collapses of Cumbre Vieja or Kilauea volcanoes are extremely unlikely to occur in the near geologic future. The flanks of these island stratovolcanoes will continue to slip aseismically, as in the past. Sudden slope failures can be expected to occur along faults paralleling rift zones, but these will occur in phases, over a period of time, and not necessarily as single, sudden, large-scale, massive collapses. Most of the failures will occur in the upper flanks of the volcanoes, above and below sea level, rather than at the basal decollement region on the ocean floor. The sudden flank failures of the volcanoes of Mauna Loa and Kilauea in 1868 and 1975 and the resulting earthquakes generated only destructive local tsunamis with insignificant far field effects. Caldera collapses and large slope failures associated with volcanic explosions of Krakatau in 1883 and of Santorin in 1490 B.C., generated catastrophic local tsunamis, but no waves of significance at distant locations. Mega tsunami generation, even from the larger slope failures of island stratovolcanoes, is extremely unlikely to occur. Greater source dimensions and longer wave periods are required to generate tsunamis that can have significant, far field effects. The threat of mega tsunami generation from massive flank failures of island stratovolcanoes has been overstated.

...

source: >> http://www.drgeorgepc.com/TsunamiMegaEvaluation.html

 

Not to worry. The next major extinction event may be heading right for us as one of the estimated 5% or so massive asteroids we haven't found yet. In such an event I marvel at how clever the survivalists have been to have already constructed their tombs. Duck duck, cooked goose.

Edited April 8, 2014 by Acme

[Acme]

Something newer about something older about something boulder.

 

Dino-Killing Asteroid Impact Dwarfed by Earlier Space Rock Crash

Scientists have reconstructed a long-ago asteroid impact that makes the strike that wiped out the dinosaurs 65 million years ago look like a playful chuck on the chin.

 

The enormous collision occurred 3.26 billion years ago and involved an asteroid 23 to 36 miles (37 to 58 kilometers) across four to six times wider than the dino-killing space rock. The impact created a crater about 300 miles (500 km) wide and generated seismic waves far more powerful than those produced by any earthquake in recorded history, researchers said.

 

The asteroid impact was "far larger than anything in the last billion years," Jay Melosh of Purdue University, who was not involved in the new study, said in a statement.

...

Edited April 11, 2014 by Acme