The volatile processes that shaped Earth

Although it is widely understood that Earth was formed gradually, from much smaller bodies, many of the processes involved in shaping our growing planet are less clear. Astronomers have now untangled some of these processes, revealing that the mini-planets added to Earth had previously undergone melting and evaporation. They also address another scientific conundrum: Earth’s depletion in many economically important chemical elements.
Geology News — ScienceDaily