I’m just looking for a fanciful map or maps of Mars which includes oceans. To be clear: I’m looking for such maps only inasmuch as they are based on Mars’s actual topography.
-FrL-
While there are indications of intermittent water flows on Mars, there’s no currently accepted observations of past standing oceans. This isn’t to say that Mars absolutely didn’t have oceans, but the majority of planetologists believe, based upon current understanding of geology and geophysics, that the phenomena claimed by some to be caused by standing water were in fact formed by other mechanisms.
Here’s a National Geographic article from a couple years about about a Mars-with-oceans theory, and here are some figures from a paper published in Science on the same topic.
Stranger
The Hellas basin is the lowest area on Mars, and in the areological past may have been the last “dead sea bottom of Barsoom” to have lost its water. I recall reading several decades ago that Hellas at midsummer noon was the only place off Earth in the Solar System where open liquid water could theoretically exist (referencing, of course, surface air pressure and temperature). Whether that’s true now with our improved knowledge of Mars is not something I would venture a guess on.
Many if not most of the “areographical” feature names used today were based on water features, because that’s what early astronomers thought they were. “Lake of the Sun” and “Noonday Gulf” are examples.
The Mars add-on pack for NASA’s WorldWind (there’s a Moon pack too) will show everything in pseudo or actual 3D, in an image resembling Google Earth.