Undersea volcanic activity has been blamed for a mass extinction in the seas 93 million years ago.

[Dover]

Undersea volcanic activity has been blamed for a mass extinction in the seas 93 million years ago.

In the so-called "anoxic event" of the late Cretaceous Period, the ocean depths became starved of oxygen, wiping out swathes of marine organisms.

Researchers from the University of Alberta, Canada, found a tell-tale signature of underwater volcanism in rocks dating to the period.

Their findings have been published in the journal Nature.

At the time of the anoxic event, the average temperatures were higher than those of today, researchers say.

Palm trees grew in what would later become Alaska and large reptiles roamed northern Canada. The Arctic Ocean was ice-free and scientists think it would have had a temperature we might describe today as lukewarm.

However, the oceans were also hit by a mass extinction which wiped out a type of large clam common at the time as well as tiny ocean creatures known as foraminifera, which live on the sea floor.

Ocean chemistry

Helped by a sudden sluggish shift in ocean circulation, the remains of these minuscule organisms littered the sea bed in thick layers, and over geological time became transformed into oil...cont'd

http://news.bbc.co.uk/2/hi/science/nature/7510541.stm

[jwirr]

1. Was this from the series "Earth: The Biography"? I noticed that

it was sponsored by GE, and several oil companies. Also it seemed to be saying that these climate changes are natural and are happening all the time. Otherwise I liked the series.

[DCKit]

2. At did what latitude did Alaska, northern Canada and Antarctica rest...

when the dinosaurs were roaming around and chomping the tops off those palm trees?

I'm not criticizing, just saying they should have presented all the information. Only the Xians believe everything exists as it has always been (I'm imagining German T-Rex's running around wearing Nazi cross armbands).

As much as I love watching the science shows, their explanations are far too often simplistic. Granted, they're playing to an audience of morons, but those morons are going to remain ignorant until they're challenged to think. They need to start tying all this shit together - climate, continental drift, extinction events, asteroid/comet impacts.... It'd be a hell of a series.

As to the sponsorship of those shows, sure, climate change has always been, but when that particular extinction event took place, better than 70% of all species were wiped off the planet. Shouldn't we be doing our bit to make sure we're not causing that kind of catastrophe by burning every scrap of sequestered carbon that ever existed? Few of us are prepared to struggle and scrape every day simply to survive, and it's doubtful that any apex predator survived that particular event, no matter how wealthy or smart they were.

The extra CO2 in the atmosphere is already causing acidification of the oceans and, aside from the obvious effects to plankton and shellfish, I haven't seen any postulation about what's going to happen to the geology, fish, plankton and cetaceans, or the massive deposits of methane hydrate on the ocean floor - the same deposits that were very likely disturbed by those same volcanic eruptions and further exacerbated runaway global warming.

It's all connected and we don't need to be poking Mother Nature with a stick until we understand the full consequences of our actions.