Chevron determined the best place would be the Dupuy Formation, a geologic layer a mile beneath Barrow that contains a saline aquifer.

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And echoing through the ancient temple is the sound of a river flowing even beneath this layer, running through a Republic-era drain.

BBC: Going underground at the Colosseum

It appears the major sticking point concerns the depth of the memory layer on which data is written: HD-DVD favors a data layer 0.6mm beneath the surface of the disk, the same depth as on the current generation of DVDs.

ENGADGET: DVD format war: Matsushita says Toshiba needs to give up

Morning comes, and the boar tracks are buried beneath a fresh layer of thick, pristine snow.

BBC: Poland's wild woods

Unlike Blu-ray, which has a much shallower (and therefore a more delicate) data layer, an HD DVD has its digital information etched deeper beneath the surface just like a conventional DVD and can therefore be stamped out on much the same sort of equipment as a DVD.

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Methane is the principal component of natural gas, and massive amounts of it are trapped in reservoirs beneath the sea floor and under a layer of the ice-like substance.

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But just beneath Portland's bohemian top layer is a stately town that's almost Midwestern in its decency, set against a stunning natural backdrop.

WSJ: Insider's Travel Guide to Portland, Oregon | Journal Concierge