Why does Venus lack surface plates?
The surface of Venus is rather smooth in many places, though not nearly as smooth as originally expected . However, we find evidence for many of the same geological features found on Earth: canyons, volcanoes, lava flows, rift valleys, mountains, craters, and plains. There is substantial evidence for local tectonic activity but the surface appears to be a single crustal plate, with little evidence for large-scale horizontal motion of crustal plates as found on the Earth. Why the two planets differ in this aspect of their geology even though we believe them to have similar interiors is not well understood. The usual explanation is that Venus is a little behind the Earth in geological timescale, and its tectonic activity is just getting started. Subduction plays a more fundamental role than seafloor spreading in determining the earth’s plate tectonics. The gravity-controlled sinking of a cold, denser oceanic slab into the subduction zone (called ‘slab pull’) dragging the rest of the plat
