Did dinosaur-killing asteroid trigger largest lava flows on Earth?

[orogenicman]

All the way back when I was a student at U of L, when the asteroid impact hypothesis for the extinction of the dinosaurs was first published, I have been a skeptic that it could have been the sole contributor. I have always said that the Deccan Trapps flood basalts were just as likely candidates. Now there is more definitive evidence that it could be true. I feel vindicated.

Did dinosaur-killing asteroid trigger largest lava flows on Earth -- ScienceDaily

Date:
April 30, 2015
Source:
University of California - Berkeley
Summary:
The theory that an asteroid impact killed off the dinosaurs 66 million years ago is well accepted, but one puzzle is why another global catastrophe -- the huge, million-year eruption of the Deccan Traps flood basalts in India -- occurred at the same time. Geologists now argue this is not a coincidence. The impact probably rang Earth like a bell, reigniting an underground magma plume and generating the largest lava flows on Earth.

Some of us have long made that argument. What was missing was more convincing evidence. This is more convincing to me that anything I've read yet. Obviously, more work is needed.

 

[Old Rocks]

It does make a lot of sense. Both in the physics of the effects of the impact on a plume, and the double whammy to existing life. Impact, immediate climate change to very cold compared to what was before. Very acid rain worldwide because of the sulpher content of the limestone the asteriod impacted. And both the impact and following eruptions contributing a massive amount of GHGs, you would have, during clear periods, very warm conditions, then during major eruptions, cold periods. Very rough on the existing ecology.

 

[waltky]

Dinosaurs May Have Been Done In by One-Two Climate Punch...

Research: Dinosaurs Done In by One-Two Climate Punch
July 07, 2016 WASHINGTON—New evidence suggests volcanic eruptions and asteroid impact 150,000 years later caused two dramatic spikes in global temperature, which together, meant doom

In the boxing ring, a one-two punch can often mean a knock-out victory. In the great outdoors, it can mean extinction. New research suggests that's what led to the demise of the dinosaurs. The giant reptiles ruled the earth for about 160 million years. Then, 66 million years ago, at the end of the Cretaceous Period, they disappeared. The dinosaurs' extinction followed two catastrophic events that literally rocked their world: a huge eruption of the Deccan Traps volcanic range in what is now India that spewed poisonous levels of carbon dioxide and sulfur into the atmosphere, and then, just 150,000 years later, the crash of a 12-kilometer-wide asteroid into the coast of Mexico which threw up a cloud of dirt and rocks that blocked the sun across the globe. Scientists have argued for decades about which of those event spelled disaster for the dinosaurs, but without a window into the past, the debate remained theoretical. Now, on an Antarctic island near the southern tip of South America, tiny fossilized clams may have provided an answer.

New evidence suggests that volcanic eruptions and an asteroid impact 150,000 years later caused two dramatic spikes in global temperature, which together, doomed the dinosaurs.​

Separating the environmental impacts
Archeologists have found ample evidence of both the volcanic eruptions and the asteroid strike. However, with only 150,000 years separating them, layers of sediment from the two events are so close together in the rock record that it’s very difficult to distinguish the effects of one, or the other.But University of Michigan paleoclimatologist Sierra Petersen told VOA, “At Seymour Island there’s 40 meters separating those two events, so we can really separate the influences of each one and that’s why we can see the climatic impacts of both as two separate events.” It turns out, says Andrea Dutton, now a geochemist at the University of Florida, "really [proponents of the volcano and asteroid impact theories] were both right.”

The rock record on Seymour Island provides a clear picture of changes in the ancient climate​

When Dutton was a graduate student at the University of Michigan, she tried to use fossilized shells from Seymour Island to study ancient climate changes. Her technique involved measuring levels of oxygen molecules in the fossils. But the numbers she came up with could be explained by both the temperature and the salt content of the water in which the shells formed. This made it difficult to interpret the results. So the fossils got shelved until Petersen showed up with a new technique. That analysis focuses on the types of carbon molecules present in a shell, which depend strongly on the water temperature when that particular layer of shell formed. So, for the first time, it was possible to determine the temperature record during the last days of the dinosaurs. And the record showed that things got hot. Twice.

Ancient global warming

“Preceding the impact event, at the time when the Deccan Traps volcanism in India began," Petersen explained, "we found a rapid warming spike that had not been seen before. We also found at the boundary itself when the meteorite hit ... another warming spike.” It was the ultimate one-two punch. If the dinosaurs thought the acid rain and volcanic dust were bad, things only got worse with the rapid temperature increase that followed. Dutton explains that the animals and plant life “had experienced temperatures this warm earlier in the Cretaceous, but what happened here was the temperature increase was so fast that it was a large stress ... they weren’t able to adapt that quickly.” Species that survived the first warming spike were quickly - at least in geologic terms - hit by another blow -- the asteroid impact, which also caused the temperature to rise. "We’re not necessarily saying that the warming is what killed everything at that time," Dutton stressed, "but it could have made things worse and it could have been responsible for part of that extinction."

Four bivalve specimens from Antarctica’s Seymour Island analyzed in the University of Michigan-led study, showing the range of sizes of the different mollusks.​

In any case, she and co-author Petersen suggest we pay close attention to their findings, reported in Nature Communications, because the effects of rapid climate change in the Cretaceous are eerily similar to the effects scientists are seeing now from global warming. “The volcanism preceding the meteorite impact put stress on that environment in the same way that the anthropogenic CO2 emissions we are doing now are putting on the environment today,” Petersen noted. “We are already seeing extinctions and certain organisms being under a lot of environmental stress. All of the same things we are observing today would have been in play during the Cretaceous as well.” “So,” she added with a nervous chuckle, “fingers crossed for no meteorite impact.”

Research: Dinosaurs Done In by One-Two Climate Punch

See also:

Dwarf Dinosaur Suffered from Jaw Tumor
July 06, 2016 - Millions of years ago in what is now the central Romanian region of Transylvania, a dwarf dinosaur walked the earth with a non-cancerous facial tumor similar to those found today in humans, other mammals and some reptiles.

The fossilized jaw of a Telmatosaurus transsylvanicus, a “type of primitive duck-billed dinosaur known as a hadrosaur,” was recently unearthed by researchers at the University of Southampton and is the first time a tumor has been discovered in a fossilized dinosaur. “This discovery is the first ever described in the fossil record and the first to be thoroughly documented in a dwarf dinosaur,” Kate Acheson, a PhD student at the University of Southampton. “Telmatosaurus is known to be close to the root of the duck-billed dinosaur family tree, and the presence of such a deformity early in their evolution provides us with further evidence that the duck-billed dinosaurs were more prone to tumors than other dinosaurs.”

A young Telmatosaurus hunted by the predator Balaur bondoc.​

The Telmatosaurus lived some 67-69 million years ago and was found in what is called the “Valley of the dinosaurs" in the Haţeg County Dinosaurs Geopark in Transylvania, western Romania, also a UNESCO site. “It was obvious that the fossil was deformed when it was found more than a decade ago but what caused the outgrowth remained unclear until now,” says Dr Zoltán Csiki-Sava of the University of Bucharest, Romania, who was involved in finding the fossil. “In order to investigate the outgrowth, our team was invited by SCANCO Medical AG in Switzerland to use their Micro-CT scanning facilities and to ‘peek’ un-intrusively inside the peculiar Telmatosaurus jawbone.”

A reconstruction of the young Telmatosaurus individual.​

The tumor is known as a ameloblastoma, a benign growth that is found in the jaws of humans and other animals and reptiles. Researchers say the dinosaur likely did not suffer any pain during the early stages of the tumor, but it died before being fully grown, and researchers are unsure if the tumor contributed to the creature’s death. “We know from modern examples that predators often attack a member of the herd that looks a little different or is even slightly disabled by a disease. The tumor in this dinosaur had not developed to its full extent at the moment it died, but it could have indirectly contributed to its early demise,” said Csiki-Sava.

Dwarf Dinosaur Suffered from Jaw Tumor

 

[IsaacNewton]

The KT extinction also wiped out many other species. Including species of plankton, land plants, and insects. It was a bad day for life on Earth. The worst extinction, the PT mass extinction roughly 242 million years ago saw 90-95% of all species go extinct. It took 10-20 million years for life to recover from that. A moment in time when life on Earth hung by the thinnest of threads.

And it does look like there was something of a decline already happening regarding the dinosaurs when the asteroid struck.

 

[SixFoot]

I always figured an asteroid that big would have no problem causing all sorts of volcanoes/super volcanoes to erupt wildly.

Is there also evidence to suggest that plate tectonics could have been affected?