Stegasaour is Jurrasic (1 Viewer)

[SaparotRob]

I am going to have to ask for more information as I have zero details on your chosen subject.

Does it have stegasaour?

See Farside cartoon "What really killed the dinosaurs".

 

[Thumpalumpacus]

I am going to have to ask for more information as I have zero details on your chosen subject.

Does it have stegasaour?

As I posted above:

 

[SaparotRob]

As I posted above:

View attachment 635589

And yes, it is now OFFICIALLY called the thagomizer in paleontology circles.

 

[The Basket]

What killed of the dinosaur?

I have no idea.

Probably volcanoes.

Yeah volcanoes.

 

[GrauGeist]

Or Climate Change (as in very sudden and violent climate change).
Giant meteors will do that, you know...

 

[The Basket]

Plenty of history of Volcanoes throwing so much gunk into the sky it blocks the sun and freezes the Earth.

Don't get me wrong, I am waiting for the comet to smash into the Earth to kill us all as much as the next guy
but that ship ain't sailing.

but volcanoes have a track record so that's where the smart money is.

 

[SaparotRob]

 

[GrauGeist]

It is true that periods of extreme Volcanic activity have influenced earth's history like the Lake Toba supervolcano 75,000 years ago (it's most recent) and even the heightened volcanic activity that led to the "Little Ice Age" starting in the 13th century (which had direct influence on human history) and even more recently, Krakatoa, which was one of the best documented events that had direct influence on the climate.

However, the Yucatan event presents a direct end to the Cretacious and a massive shift in the earth's ecology.
Last day of the dinosaurs' reign captured in stunning detail

 

[The Basket]

Were cigarettes around at the time of the dinosaurs? Perhaps the end of the dinosaurs was lung cancer.

Although I like how the Trexs are sharing a match. Shows that T Rex were social animals who didn't mind giving a brother a light.

My only concern with this picture is that the colours could be wrong. Thankfully no feathers are on show.

 

[special ed]

What was the wingspan of that giant Meteor?

 

[GrauGeist]

What was the wingspan of that giant Meteor?

6 miles.

 

[The Basket]

Just reading about the impact
Bad day to be a T-Rex. Although my boy Steggy was cool with it as he died out years before.

Odd to think that random chance of a comet strike is why us monkeys are here today. Otherwise we could be velociraptors on Google instead.

 

[Thumpalumpacus]

However, the Yucatan event presents a direct end to the Cretacious and a massive shift in the earth's ecology.
Last day of the dinosaurs' reign captured in stunning detail

Not only have they located and mapped the crater -- which dates correctly to both the fossil record of extinctions as well as the iridium layer that is essentially worldwide -- the vulcanism on the Indian subcontinent appears to have waned 300,000 years or so before extinctions rose. It may, or may not, be that the Shiva vulcanism stressed ecological systems, priming them for the impact event.

That being said, the ejecta from the impact are scattered far and wide, including iirc glass sphericles found in the Pacific near Hawaii which are detritus direct from the impact-site itself, as well a fossil zone in North Dakota littered with them, as well as evidence of tremendous turbulence generated by the tsunami the event generated (remember, central North America was at that time a large, shallow sea):

And at Tanis, the fossils record the moment this bead-sized material fell back down and strafed everything in its path.

Fish are found with the impact-induced debris embedded in their gills. They would have breathed in the fragments that filled the water around them.

There are also particles caught in amber, which is the preserved remnant of tree resin. It is even possible to discern the wake left by these tiny, glassy tektites, to use the technical term, as they entered the resin.

Geochemists have managed to link the fallout material directly to the so-called Chicxulub impact site in the Gulf. They have also dated the debris to 65.76 million years ago, which is in very good agreement with the timing for the event worked out from evidence at other sites around the world.

From the way the Tanis deposits are arranged, the scientists can see that the area was hit by a massive surge of water.

Although the impact is understood to have generated a huge tsunami, it would have taken many hours for this wave to travel the 3,000km from the Gulf to North Dakota, despite the likely presence back then of a seaway cutting directly across the American landmass.

Chicxulub asteroid impact: Stunning fossils record dinosaurs' demise

Remarkable specimens shed light on the minutes and hours following the Earth-changing asteroid strike.

www.bbc.com

Whatever other difficulties were unbalancing ecology around the world at the time, and excessive vulcanism can be a dangerous one, I think it's pretty well-settled that the K/T impact was the main driver behind that mass extinctions at that boundary.

 

[GrauGeist]

Yes indeed, the meteor impact was about as perfect as such things can be.
If it was smaller, it would just made a mess, if it were larger, it would have been a planet killer.
If it's trajectory was like that of a Stuka's, it would have been catastrophic, if it's angle were shallower, it would have most likely ricocheted back into space, taking a large amount of debris with it.
As it happens, it's mass and angle were perfect, rocking the earth 20° on it's axis which in turn, allowed the earth to have seasons.

Incidentally, unlike the movies, the time between the meteor entering the atmosphere and impact was minutes.
Also, due to it's speed and mass, it wasn't some flaming red ball that people could look up and point at, it was a brilliant ultraviolet mass of light that would have melted the face off of an onlooker in the vicinity of it's approach and blinded onlookers thousands of miles away - so not much good for hollywood...

 

[Thumpalumpacus]

Yes indeed, the meteor impact was about as perfect as such things can be.
If it was smaller, it would just made a mess, if it were larger, it would have been a planet killer.
If it's trajectory was like that of a Stuka's, it would have been catastrophic, if it's angle were shallower, it would have most likely ricocheted back into space, taking a large amount of debris with it.

The other thing: had it been 800 or 1000 miles eastward, striking in deep ocean, it wouldn't have blasted so much seafloor into the atmosphere, and would likely have had much-reduced climatological repercussions; rapid cooling well before it hit the seafloor would have blown it apart. There still would have been a huge tsunami, but 1) probably not as big and 2) not shrouding the atmosphere with particulates.

As it happens, it's mass and angle were perfect, rocking the earth 20° on it's axis which in turn, allowed the earth to have seasons.

I think the axial tilt of the Earth long predates this event. There's strong evidence of seasonal bias in the fossil record long before 65 mya. It's believed that the axial tilt resulted from the strike that was strong enough to blow off the material that eventually formed the Moon.

 

[GrauGeist]

The moon was formed roughly 4.5 billion years ago when the earth collided with another (smaller) planet while the solar system was young.

At that time, the earth was an inhospitable mess as things were still cooling down from the solar system formation.

 

[Thumpalumpacus]

The moon was formed roughly 4.5 billion years ago when the earth collided with another (smaller) planet while the solar system was young.

At that time, the earth was an inhospitable mess as things were still cooling down from the solar system formation.

Indeed. Being young, Earth's axial rotation was likely much more perpendicular to the plane of orbit. It got smacked and knocked on its side early in its development, which blew off most of the impactor and much of Earth. As the Moon coalesced, it exerted gravitation tides that pulled Earth back closer to a vertical axis, so that the Earth is now about 23° askew from the orbital plane instead of the 70° post-impact; and all the while the Sun has been pulling the Moon away from Earth, lessening its gravity and reducing its ability to straighten our Earth out any further.

What hit us at Chicxulub was much smaller than the strike which created the Moon, and simply didn't have the force to tilt 6.6 sextillion tons 23° over on its side. It was too small to instigate seasons, especially since it was hitting close to the equator (less leverage, dig?). You may as well try to tip a Peterbilt by flying a finch into it.

 

[GrauGeist]

If that Pete were floating in space, a tiny finch flying fast enough would certainly have influence on it's relative position, especially if it struck above the centerline and at a specific angle.

Here's a great and detailed examination of the event:
A steeply-inclined trajectory for the Chicxulub impact - Nature Communications

 

[The Basket]

From what I have read the axial tilt of the Earth is much older than the dinos.

The axial tilt is not fixed and so it would have altered regardless in the 65 million years anyway.

It is odd to think that the event which could have wiped out the dinos was a random event and not some long term decline.

 

[Thumpalumpacus]

If that Pete were floating in space, a tiny finch flying fast enough would certainly have influence on it's relative position, especially if it struck above the centerline and at a specific angle.

Here's a great and detailed examination of the event:
A steeply-inclined trajectory for the Chicxulub impact - Nature Communications

I'm not arguing that the K/T object did or didn't come in at a particular angle. I'm just pointing out that it simply didn't have the mass to impart a 23° tilt to the Earth's axis. Nothing in your linked article addresses that.