In a new survey of the sub-seafloor off the U.S. Northeast coast, scientists have found a gigantic aquifer of relatively fresh water that would be roughly 15,000 square mi if on Earth's surface. It is in sediment below the ocean floor. This suggests that aquifers may lie off many coasts worldwide.

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In a new survey of the sub-seafloor off the U.S. Northeast coast, scientists have found a gigantic aquifer of relatively fresh water that would be roughly 15,000 square mi if on Earth's surface. It is in sediment below the ocean floor. This suggests that aquifers may lie off many coasts worldwide.