Therein lies the rub with respect to the geological life of Mars. If tectonics are still active on Mars, then it would have to have a molten core, meaning heavy metals would be at the core. This would be indicated by a magnetic field (presuming the iron core is spinning).
Since Mars has no magnetic field, it is presumed to be dead, tectonically speaking.
I had forgotten about the core.
Mars has a spotty magnetic field, so while it still may have a core, it’s not spinning like ours. Thanks for the clarification.