Wednesday, October 11, 2017

Volcano Eruption From 16.5 Million Years Ago That Helped Cool Earth, Explained

[IB Times] Volcanic eruptions have served as cornerstones to evolution on Earth. From aiding the creation of first signs of life on Earth to the extinction of dinosaurs, volcanic eruptions constantly feature as important events in history that altered the course of planetary evolution.
Now researchers at Washington State University have determined that the Pacific Northwest was home to one of the Earth's largest known volcanic eruptions around 16.5 million years ago.
In fact, only two eruptions were larger than the one in the Pacific Northwest: the basalt flood of the Siberian Traps and the Deccan Traps.
These eruptions, a millennia-long spewing of sulfuric gas that blocked out the sun and cooled the planet, also led to large-scale extinction of life on the planet.
"These eruptions did have a global effect on temperatures, but not drastic enough to start killing things, or it did not kill enough of them to affect the fossil record," said John Wolff, a professor in the WSU School of the Environment, in a report by phys.org.
The research was funded by the National Science Foundation and published in Geology journal. It connects geological and archaeological data from across the world to connect the dots to a major, landscape changing event in our planets’ history.
The team estimated the eruption to have occurred 16.5 million years ago. Vents found in Washington and Northwest Oregon sent the flow of basalt from the eruption all the way from Canada to the Pacific Ocean.
This flow formed the Wapshilla Ridge Member of the Grande Ronde Basalt, a kilometer-thick block familiar to travelers in the Columbia Gorge and most of Eastern Washington. This is the largest basalt flood map plotted till date. Read More