Dust in Them Thar Hills

Windblown loess (pronounced "luss") forms the surface layer on many of the hills surrounding Fairbanks. The layers of silt-sized dirt particles feather out near the tops of the hills but may be more than a hundred feet thick near the bases. The layers of loess often are frozen. These contain lenses of pure ice and the remains of many mammals: bison, horse, camel, mastodon, mammoth, saber-toothed tiger and even the Fairbanks Lion.

Tall exposures of the loess remain beside the tailing piles on the roads to Ester and Fox. In earlier years the loess was washed away by hydraulic giants so that gold dredges could mine the gravels below.

Little studied, the loess is thought to have been laid down by winds during the last glacial age ending about 6,000 years ago. The loess had its source in the broad outwash plain north of the Alaska Range. Though glaciers never covered Fairbanks, they probably extended well north of the Range and carried eroded material far out from the mountains.

So the next time you curse the fine dust tracked into the house, remember that it may have had a lofty origin atop Mt. Hayes or one of the other spectacular peaks out across the valley.