FEATURES

22 Salt of the Earth
For nearly a century, iodine has been added to table salt to combat iodine deficiency. Now health officials in Guyana are using salt to deliver a parasite-killing drug in the hopes of eradicating a debilitating disease. But will it work?
Cassandra Willyard

28 Beer or Biofuels
Headlines all over the world proclaim that food — and beer — prices are climbing as supplies are short because of biofuels production. No doubt beer and food are costing more, but are biofuels really to blame?
Megan Sever

34 Summer Road Trip: Driving Across the Northern United States
The summer road trip — taking the long, scenic route — is certainly a throwback to times before high gas prices and frequent flyer miles. But if you take the time, the northern United States offers myriad geological wonders.
Callan Bentley

NEWS NOTES

7 News Shorts
8 Turning Iraq’s water back on
9 California’s impending “big one”
10 Up in smoke
11 Landmine detectors thwarted by soils
12 Gold fever strikes again
13 Oil industry tries biofuels matchmaking
14 The ties that bind
15 Earth hums a new tune
15 Fossilized feces tell an old tale
16 Oil in the Great Plains
17 Thorium fuels nuclear comeback
18 A slip-sliding Earth?
19 Europe’s deep energy
20 Mineral resource of the month: natural and synthetic zeolites

VIEWS

59 A COMMENT ON...
Oil and War
Oil is not as important to U.S. national security as politicians might think. The United States needs to understand that trying to influence oil supply with military force is counterproductive.
Clifford Singer

60 GEOLOGIC COLUMN
The Agony of Victory
China has been working hard to clear the air in Beijing before the Olympics begin in two months. But whether they’ve done enough remains a subject for debate.
Fred Schwab

DEPARTMENTS

4 FROM THE EDITOR
5 LETTERS: Perspectives from readers

40 TRENDS & INNOVATIONS
Resuscitating Ocean Thermal Energy
Imagine a power plant that generates a never-ending supply of electricity without emitting carbon dioxide. It’s a real possibility, and researchers are working to make it happen in Puerto Rico and elsewhere.
Erin Wayman

43 GEOMEDIA
Shows: The Evolution of a Science Comedian
Movies: 10,000 B.C. Should Have Stayed in the Pleistocene
Web: Geology Bloggers Rock
Web: Science Bloggers Question Their Role

48 CROSS-SECTION: A puzzle
49 WHERE ON EARTH?
50 GEOMARKETPLACE
52 CLASSIFIEDS: Career opportunities

56 BENCHMARKS
June 7, 1692: Earthquake Levels Port Royal, Jamaica

57 DOWN TO EARTH WITH...
Environmental Geographer and Genius Grant Winner Ruth DeFries

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