This just in. Well, that is, it was 'just in' about 1,250 years ago. And not here. Europe. Well, here and there. By 'here' I mean... maybe a pitcher or two'll tell the story better. First, there was this on Facebook, from our friend Breck Parkman.
That led me to the 'official' announcement, from the University of Alaska Fairbanks Geophysical Institute: "White River ash made its way across the globe." Ash dated to about 860 C.E. has been recovered in places across northern Europe. However, its origin was an enigma until now. Britta Jensen and Duane Froese (University of Alberta) have apparently solved a long-standing mystery of European geology.
The White River Ash blasted from giant eruptions somewhere in today’s Wrangell-St. Elias Mountains, drifted as far away as Ireland and Germany, said experts who attended the December 2012 Fall Meeting of the American Geophysical Union, held in San Francisco.Near the source, the ash-fall was impressive, as the photo below illustrates.
The Wrangell--St. Elias Mountains lie in southern Alaska. As you can see from the Google earth graphic below, they're almost half a world away from Ireland and Germany.
As for the topographic character of the present-day place of origin, the image below gives some idea of the 'bowl' presumed to be the remnant of the enormous explosions of ash. Mounts Churchill and Bona are indicated. It's possible to see the huge snow-free scarp immediately downslope, and another, nearer the bottom of the photo, evincing another large, arcuate head scarp.
|For scale, the two peaks are 4.14 km apart. Vertical scale exaggerated 1:2. (Source: Google earth.)|
Catch you next time!
SA announces new posts on the Subversive Archaeologist's facebook page (mirrored on Rob Gargett's news feed), on Robert H. Gargett's Academia.edu page, Rob Gargett's twitter account, and his Google+ page. A few of you have already signed up to receive email when I post. Others have subscribed to the blog's RSS feeds. You can also become a 'member' of the blog through Google Friend Connect. Thank you for your continued patronage. You're the reason I do this.