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Practice Reading: Multiple Choice, Single Answer
ID: #4386
Oil
When oil flows from reservoirs underground to the earth's surface, it becomes exposed to bacteria and air. This causes the oil to degenerate into a thick, syrup-like substance called bitumen. Bitumen's thickness and tendency to mix with other surface elements, such as sand and clay, make it extremely complicated to 'mine'. The extraction process requires digging up huge amounts of sand or earth with enormous machines and heating it to 80 degrees centigrade in order to liquefy the bitumen and make it easier to separate. Compared to traditional oil drilling, extracting surface oil is expensive and inefficient. Nevertheless, surface oil is becoming more competitive as traditional oil sources become more scarce.
What are the writer's views on surface oil?
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