About 850 km (530 miles) north of Vancouver, B.C.
“About two years ago, geologists studying an ocean channel near Ketchikan, Alaska, spotted something unusual,” writes Ed Schoenfeld in the Coast Alaska News.
It was a dormant submerged volcano, about 150 feet below the surface. Experts estimate that it hadn’t erupted for about 10,000 years.
Now, another underwater volcano has been discovered near Dixon Entrance, north of Prince Rupert, B.C. and south of Ketchikan, AK., about 850 km (530 miles) north of Vancouver, B.C.
This one is active, busily pumping out a plume – actually multiple plumes – of methane gas.
The gas plume is coming from a volcanic vent about 3,000 feet below. It stretches up about two-thirds of the way to the ocean’s surface, rising about 700 meters into the water column.
But there was no fresh lava — or anything else to worry about, said Dr. H. Gary Greene, a marine geologist working with the Sitka Sound Science Center.
Green, along with his Canadian counterpart Dr. Vaughn Barrie (Geological Survey of Canada), found the volcano Sept. 23 during a study of the Queen Charlotte-Fairweather Fault System.
“This fault acts as a conduit to deeper in the Earth to places where either magma or fluids that are heated by magma or geothermally heated at depth can migrate up through the fault to the surface,” said Greene.
Greene said the study also found other volcanoes nearby, but none were active.
In addition, several other venting volcanoes have been found along the same fault system in recent years off the shores of British Columbia.
So. We now know that there are several active underwater volcanoes – no one knows how many – off the coasts of both Alaska and British Columbia.
We also know that these are areas where geothermal heat “can migrate up through the fault to the surface.”
And we wonder what is heating the seas?
Thanks to George Martinez for these links