Oceans may be shrinking — Science News, March 10, 1973
According to scientists, the ocean’s leak can be traced back to subduction zones, where tectonic plates collide and the heavier of the two sinks into the mantle. It is still unclear how much water has cycled between the deep ocean and mantle throughout history. In 2019, an analysis suggested that sea levels have dropped by an average of up to 130 meters over the last 230 million years, partly due to the breakup of Pangea, which created new subduction zones. Meanwhile, scientists reported in 2022 that molten rock that bubbles up from the mantle as continents drift apart may “rain” water back into the ocean. However, since Earth’s mantle can hold more water as it cools (SN: 6/13/14), the mass of the oceans may shrink by 20 percent every billion years.
2023-03-17 06:00:00
Source from www.sciencenews.org