Venus’ crust is broken up into chunks that shuffle, jostle and rotate on a global scale, researchers reported in two talks March 20 at the Lunar and Planetary Science Conference.
New maps of the rocky planet’s surface, based on images taken in the 1990s by NASA’s Magellan spacecraft, show that Venus’ low-lying plains are surrounded by a complex network of ridges and faults. Similar features on Earth correspond to tectonic plates crunching together, sometimes creating mountain ranges, or pulling apart.
Geologists generally thought rocky planets could have only two forms of crust: a stagnant lid as on the moon or Mars — where the whole crust is one continuous piece — or a planet with plate tectonics as on Earth, where the surface is split into giant moving blocks that sink beneath or collide with each other. Venus was thought to have one solid lid (SN: 12/3/11, p. 26).
Instead, those options may be two ends of a spectrum. “Venus may be somewhere in between,” Byrne said. “It’s not plate tectonics, but it ain’t not plate tectonics.”