[2] A lid tectonic regime arises when the cold upper lithosphere is too viscous to participate in the underlying flow of the mantle.
The temperature of a body's core–mantle boundary, and the presence of water, strongly affect the rheological, composition, and thermal diagnostics of lid tectonics.
At the base of the lithosphere, where the lid is in contact with less viscous material, melts will form at the thermal boundary layer and cause drips, believed to be of peridotite composition.
[10] Solomatov and Moresi used the term "stagnant lid" when they characterized the tectonic style that was present on Venus in 1996.
[11] They stated that Venus had plumes similar to Earth, that would rise to the surface, and cold "drips" of lithosphere would sink back down.