U.S. and Russian planetary scientists developed the first complete geological map of Venus and presented it to the third Moscow Solar System Symposium on Space Research Institute (IKI) RAS.
"The map has helped us to find out what life in the earth, there were two periods of Venus - tectonic and volcanic his descendant. According to our calculations, the" morning star "is quite young - the average age of rocks on the surface is about 500 million years," - said one of the authors cards, Mikhail Ivanov of the Institute of Geochemistry, Vernadsky (Vernadsky).
Mikhail Ivanov and his colleague James Hand of Brown University in Providence (USA) made a geological map of Venus, using imagery U.S. Magellan probe while the second planet orbiting the solar system in 1990-1994, reports RIA Novosti .
Ivanov and his colleagues presented the first results of its work back in 2010, but its completion and analysis of the results took two additional years.
Preparing the map, the researchers analyzed the structure of the surface of the "Morning Star." It was found that the surface of Venus is divided into two unequal area, formed by tectonic and volcanic processes. According to them, volcanic landforms occupy the bulk of the planet. Most tectonic forms located on a hill and mountain regions of the surface, and volcanic areas - in the valleys and plains.
For example, the most ancient volcanoes, so-called shield plains occupy up to 18% of Venus relatively young volcanic plains - about 40%, and the youngest - "lobed" plain - 6%.
Geologists guess the position and structure of volcanic landforms, and concluded that they were formed "on top" of existing tectonic forms on the surface of Venus. Overall, the average age of the rocks on the surface does not exceed 500 million - one billion years, which indicates its relative youth.
It also means that volcanoes on Venus activated after weakening and stopping tectonic processes. The authors believe that this transition is associated with features in the process of cooling the planet's core. According to them, this finding will help other geologists to refine existing models of development and the formation of Venus.