Heat loss and tectonic style of Venus

After reviewing the mechanisms of heat release and the plate tectonics of the earth, the relationship between the heat release and tectonics of Venus are investigated. On earth, the tectonic style and heat release are dominated by plate tectonics, implying linear tectonics at the plate margins and linear volcanic zones (ocean ridges, continental rifts). The surface of Venus, on the other hand, is characterized by global spotty volcanism, implying that the Venusian surface is more dominated by volcanic landforms than the surface of the earth, despite the relatively low lava production rate on Venus (maximum 3 cu km/a as compared with the 20 to 25 cu km/a on earth). As plate tectonics play no large role on Venus, heat release on this planet should be dominated by conduction through a rather thin (35-45 km) lithosphere. (I.S.)