The average ship burns about 5 metric tons of fuel each day in port.

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The Japanese government has estimated that the tsunami swept about 5 million tons of wreckage out to sea.

MSN: First bit of Japan tsunami debris turns up in Hawaii

That leaves as much as about 1.5 million tons of debris afloat, U.S. officials estimate.

WSJ: Pilgrims Flock to Tsunami Relic at Agate Beach in Oregon

About 3.5 million tons sank off the coast.

WSJ: Pilgrims Flock to Tsunami Relic at Agate Beach in Oregon

One of the largest of them, the USS Abraham Lincoln (which I visited in April), weighs almost 100, 000 tons, has a full-time crew of about 5, 000 (including its permanent air wing) and can travel over 30 knots per hour.

FORBES: Fact And Comment