We can look at vast LOWLANDS /north: on average whether Mars had plate tectonics/ on Mars: they are just like Ocean Basins on Earth, without water.
Important question:than whether Mars had plate tectonics - that shaped this oceans basins and have the ability to reshape ( for exp. sink water
beneath)? And water to act like a natural lubricant to keep the sheets of crust in motion.
. "If one believes early Mars was wet, then it makes plate tectonics more reasonable," says Gerald Schubert of the University of California, Los
Angeles. "Alternatively, one could turn this around ? accept plate tectonics, and use this as independent support for a lot of water on early
Mars."
Terra Sirenium - big highland on southern hemisphere was observed by the Mars Global Surveyor - " Surveyor detected buried magnetic fields four times
stronger than those it had recorded in the northern region.
One interesting theory, published in 1999 is that these bands could be evidence of the past operation of plate tectonics on Mars, although this
has yet to be proven [2]. If true, the processes involved may have helped to sustain an Earth-like atmosphere by transporting carbon rich rocks to the
surface, while the presence of a magnetic field would have helped to protect the planet from cosmic radiation.
Plate Tectonics on Mars
NASA
And again - water!?!? New deposit - in a time span of JUST 5 YEARS?