The study of Venus continues

Data obtained on Venusian geology, petrology, and mineralogy by the Venera-13 and Venera-14 spacecraft are reviewed. It is noted that the data give an idea of the basic types of magmatic rocks which have developed within the limits of the three structural-morphological types of the Venusian surface, corresponding to the three tectonic and magmatic stages of its evolution. Substantial analogies are found in the geological development of the earth and Venus, though the abundance and composition of magmatic products covering these planets are different. This is probably connected with different temperatures on the planetary surfaces and the removal of water from the geochemical cycle of Venus at the earliest stages of its existence.