How can Mars stay "alive" geologically?
With a lack of any large moons, being further from the Sun, an incredibly weak and spotty planetary magnetic field, and a presumably aging and dynig core, what would keep a volcano going on Mars these days?
As I recall, the Viking 2 lander did not pick up any significant earthquakes (Viking 1's was jammed when the pin would not release). I don't believe any of the other landers or rovers have had a seismometer.