Tar Sands Fields

Discovered 1899, San Joaquin Valley, California, billions of barrels of heavy oil....

Discovered 1894, San Joaquin Valley, California, the largest heavy oil field in the state....

Known since the 1930s, onshore Venezuela, roughly 300 billion barrels of extra heavy oil....

Discovered 1941, Sumatra, Indonesia, the largest steam flood project in the world....

Commercial production since 1967, northern Alberta, the core of Canadian crude reserves....