The proposed existence of magnetic lineations in the Terra
Cimmeria and Terra Sirenum regions of Mars was initially explained
by Earth-like sea-floor spreading. Here we argue instead
that these lineations could have been formed at a convergent plate
margin through collision and accretion of terranes. A similar process
produced banded magnetic anomalies, similar in geometry and
even in size to those in Earth’s North American Cordillera. Because
only sparse and generally weak anomalies have been detected
in the martian northern lowlands, which could constitute an analog
to the terrestrial oceanic crust, it is possible that the magnetic
field stopped its activity while crustal recycling was still active in
Mars
