Mars has one of the largest volcanoes in the solar system, covering an area the size of France and rising more than 20 kilometers high. Recently, scientists have discovered that it may have been an island in the vast sea in the past.
Olympus Mons is a shield volcano on Mars and the highest known mountain on all planets in the solar system. It is 21,229 meters above the datum, more than twice as high as Mount Everest on Earth. Oddly, Olympus Mons does not have a smooth slope to the ground. Instead, the edges of the mountain both visibly drop into cliffs at a height of about 6 km. The origin of this feature remains a mystery.
According to the latest analysis by CNRS researchers, Olympus Mons is similar in shape to many active volcanic islands on Earth (Pico Island in Portugal, Fogo Island in Canada, Hawaii Island in the United States, etc.), and the upper edge of the main cliff of Olympus Mons is likely to be Formed by the contact of liquid water with volcanic lava, and the northern side of Alba Mons (Alba Mons), which is more than 1,500 kilometers away from Olympus Mons, also has similar features. Therefore, the team believes that most of the low-lying places in the northern part of Mars should have been a liquid ocean. Olympus Mons was once a volcanic island surrounded by liquid water.
These clues can enrich the history of Martian water. For example, the height of the cliff represents the sea level of the long-lost ocean, and the age of the lava flow can be traced back to about 3 billion to 3.7 billion years ago, which is equivalent to the time when the ocean appeared.
new paperPublished in the journal Earth and Planetary Science Letters.
(Source of the first picture:Flickr/Andrea Luck CC BY 2.0）
