A storm of fire and ice led to ‘snowball Earth,’ says new study.
During the largest glaciation event in history – called the ‘Sturtian snowball Earth’ event – ice covered our planet from pole-to-pole, Harvard scientists say. They have pinpointed the start of that event to about 717 million years ago.
At about the same time, a huge volcanic event known as the Franklin Large Igneous Province devastated an area stretching all the way from present-day Alaska to Greenland.
We’re talking about an immense area. The Franklin Large Igneous Province covers more than 2,000,000 square km (770,000 sq miles), about the size of all of Mexico. And it’s all buried beneath a layer of basalt some 1.1 km (3,600 ft) deep.
The researchers wonder if the sulphur dioxide emitted by this huge volcanic event might have rapidly cooled the Earth.
I wonder, of course, how much of that ancient volcanic activity took place under water. That would have heated the water, thereby pumping huge amounts of moisture into the skies, skies already cooled by the above-water volcanic activity. And then – wham! – instantaneous ice age.
As I say in Not by Fire but by Ice, “warmer seas and colder skies…a deadly combination (Chapter 10, Fish Stew.)
By the way, I think it is no coincidence that the Deccan Traps in India can be associated with the K-T extinction, or that the Siberian Traps in Russia can be associated with the Great Permian extinction.
Thanks to John Topal for these links