A city lost at the bottom of the ocean might have become a cradle of the evolution
About two years ago a deep-water hydrothermal system was discovered. As it turned out later, the system existed for 30 thousand years already. Researchers say that similar systems probably existed on the Earth and on other planets for millions of years and even could become incubators of life.
A rocky column of minerals and microorganisms called the Lost City is situated at the depth of 2,500 meters below the Atlantic Ocean surface. The column is 55 meters high; it is higher than any other hydrothermal system. Below, under its structure, water is going through the cracked Earth crust. The mineral serpentine is formed as a result of chemical reaction; this process also emits heat. Water warmed and enriched with minerals gets back to the ocean; on its way back the water rebuilds the unique structure of the Lost City.
As light and nutrients essential for life are in deficit at the sea bottom, hydrothermal springs are really very popular among all microorganisms. In this respect, the Lost City is unique as it is the only hydrothermal system which scientists know as heating water in the course of a chemical reaction, but not as a system of volcanic activity. Researchers from the University of Washington who studied the system think that if the hydrothermal spring can exist without a volcano this means that the number of places at the sea bottom where life could appear in the early periods of the Earth was much greater.
Researchers say that in the early periods of the Earth many hydrothermal springs were active thanks to formation of serpentine. The Earth mantle wasn't yet covered with the thick crust and it could easily contact with the sea water. Under the present-day conditions this process requires deep cracks in the Earth's crust.
Processes of this kind may occur on other planets as well. Peridotite is the key component of the Lost City's system that interacts with the sea water; this component is abundant on other planets of the Solar System. This means that such hydrothermal systems may function on Jupiter's iced satellites where oceans are believed to exist under the ice.