Crust (geology) Crust (geology) In geology, the crust is the outermost solid shell of a rocky planet, dwarf planet, or natural satellite. It is usually distinguished from the underlying mantle by its chemical makeup; however, in the case of icy satellites, it may be distinguished based on its phase (solid crust vs. liquid mantle). The crusts of Earth, Moon, Mercury, Venus, Mars, Io, and other planetary bodies formed via igneous processes, and were later modified by erosion, impact cratering, volcanism, and sedimentation. Most terrestrial planets have fairly uniform crusts. Earth, however, has two distinct types: continental crust and oceanic crust. These two
The Future and Its Enemies The Future and Its Enemies The Future and Its Enemies: The Growing Conflict Over Creativity, Enterprise, and Progress is a 1998 book by Virginia Postrel where she describes the growing conflict in post-Cold War society between "dynamism" – marked by constant change, creativity and exploration in the pursuit of progress – and "stasism", where progress is controlled by careful and cautious planning. Postrel endorses the former, illustrates the differences between the two, and argues that dynamism should be embraced rather than feared. Richard Ebeling wrote a positive review for the Future of Freedom Foundation in May 1999. He remarked, Dr.