generalspeaking

The Great Dying

Now there's an event that shook the world. Of course there was no one around at that time who witnessed it, to make a record of it, to express their astonishment and fear, to carry the legend forward through time and recorded history. On the other hand, there was a presence that took note of what occurred. And did pass on throughout the historical fossil record that something amiss had once taken shape on this Earth.

And that something resulted in a geological and paleontological record that is just now, 250,000 millions of years later, being recognized and investigated and parsed for posterity. Actually, posterity has taken care of it. For here we are, with all our scientific capability, an intelligent investigative, scientific race of animals with big brains and opposable thumbs, capable of visualizing through decipherable evidence, an historic event that wiped out almost all lifeforms on Earth.

We know so little of what occurred all that time ago, for we ourselves did not exist then. But what did occur possibly had the potential of such complete devastation that nothing might have survived and the opportunity for new life forms to become viable might also have been so impacted that we would never, over aeons of time, have resulted. There are many, no doubt, who claim the world would have been a better place without us.

Grim, forbidding, barren, with no discernible life forms. Is that better? Canada's High Arctic islands are presenting a record of ash deposits and fossils affirming the disappearance of living organisms coinciding with a vast period in the timeless past when in present-day Siberia, a massive volcanic eruption occurred. A group of science writers have published their study in the Geological Society of America Bulletin, explicating how it was that Earth "almost became a lifeless planet."

In “The Great Dying” 250 million years ago, the end came slowly
The geology of Griesbach Creek in the Arctic tells an ancient tale of slow extinction.
Credit and Larger Version

But when the cataclysmic upheaval occurred, its results were nowhere like immediate, or even gradual as we might imagine a collapse and dying-off taking place in a period of months, even years. The study issued by the National Science Foundation, the U.S. agency that funded the Arctic research, together with NASA and Canada's NSERC research council, demonstrate that "mass extinctions need not be sudden events".

The belief that noxious fall-out occasioned as a result of the Siberian volcanoes eruptions may indicate that mercury in the environment resulted in deadly oceanic acidification, contributing to the extinction that resulted, has arisen. It is called the Great Dying, a "runaway greenhouse event", resulting from the Siberian volcanoes.

New evidence from an Ellesmere Island fiord points to primitive sponges having disappeared from the fossil record fully 100,000 years before other known species extinctions as a result of those eruptions.

"We're not sure how long the greenhouse effect lasted, but it seems to have been tens or hundreds of thousands of years", according to University of Cincinnati geologist Thomas Algeo, co-author of the GSA Bulletin study. Extinction evidence previously studied from China and elsewhere seemed to lead to the conclusion that the mass die-off "was generally abrupt". And that conclusion is being re-written.

"Based on such observations, it has been widely inferred that the extinction was a globally synchronous event."

Like folk legends of the Biblical-era-described Flood. Something that occurred at a time when humans were present and passed on dim memory of that historical record, as a globally synchronous event. The dinosaurs before us haven't left us any messages writ on stone about what occurred when a massive space object is said to have impacted Earth wiping out most species as a result of the dust storm shutting out the sun.

Science, observation and speculation. Theories and suppositions. Intelligent analyses.

Labels: Environment, Nature, Science, World News

posted by Pieface @ Tuesday, February 07, 2012