discoverynews:

The Sticky Problem With Tar Sands

To understand what tar sands are and why they have a slippery reputation with environmentalists, here’s a cheat sheet on these unconventional oil fields:

WHAT: Tar sands, also known as oil sands, are a mixture of roughly 90 percent sand, clay and water and 10 percent bitumen, a thick hydrocarbon liquid. After extracting that 10 percent of bitumen from the tar-sand mixture, the bitumen can be purified and refined into synthetic crude oil.

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