Volcanology of Mars through the crust to produce volcanic mountains. However, the largest volcano on the planet, Olympus Mons, is thought to have formed when the plates were not moving. Olympus Mons may have formed just after the plate motion stopped. The mare-like plains on Mars are roughly 3 to 3.5 billion years old. The giant shield volcanoes are younger, formed between 1 and 2 billion years ago. Olympus Mons may be "as young as 200 million years." Norman H. Sleep, professor of geophysics at Stanford University, described how the three volcanoes that form a line along the Tharsis Ridge may be extinct
The Secret of the Martian Moons that unlocks Mars’ secret. A political controversy is raging on Earth as to whether or not to continue to support the Martian outpost, where Nelson’s father is research chief. Those in favor point to the marvelous machines found on Mars, any one of which could advance civilization eons, if their secret could be discovered. Going to work on the problem, Nelson finds out – in an interesting chain of events that characterizes a Mars basically like the canal-covered red planet we know it to be now – that the Martian moons Phebos (sic) and Deimos, are centers of tyrannical factions