Tracing the Paths of Past Water Flows
This film takes the viewer on a journey along the highlands of the Xanthe Terra region, located in the Oxia Palus quadrangle (MC-11), all the way north into the lowlands of Chryse Planitia. During the flight, the viewer crosses the Martian dichotomy – a region where the heavily cratered highlands gradually transition into the smoother lowlands. The southern circumferential region of the Chryse Planitia basin is characterized by the outlets of Mars’ largest outflow channels, which converge radially into the lowlands. One of them is Ares Vallis – the focus of our previous film, Flight around Ares Vallis. The Flight around Xanthe Terra goes on to explore the path of the westernmost outflow channel: Shalbatana Vallis. Outflow channels are broad and deeply incised features, most likely formed by catastrophic flooding events in Mars' geological past, triggered by the rapid and massive release of subsurface groundwater.
Facing north, the flight begins by overflying the extensive outflow channel Shalbatana Vallis. This channel carved a deep path into the Martian surface, stretching more than 1,300 kilometers before reaching the lowlands of Chryse Planitia. Its formation likely peaked between the Middle and Late Hesperian time period, around 3.5 billion years ago. As the flight follows the channel northward, the viewer passes numerous impact craters of varying sizes – a characteristic feature of the ancient Noachian terrain.
Upon reaching the lowlands, the flight makes an abrupt right turn (facing east) and continues over a landscape of scattered knobs and hills at the southern margin of Chryse Planitia. The surface here appears smoother and shows far less impact craters than the highlands just passed. Among the randomly distributed knobs, a few small “islands” are visible – remnants that may have resisted former water flows.
After crossing the southern part of Chryse Planitia, the flight heads back southward, returning to the highlands of Xanthe Terra. It then continues over a vast region of chaotic terrain known as Hydraotes Chaos. This area is marked by a maze of irregular mesas (flat-topped) and hills (rounded), giving the region its distinctive chaotic appearance. For a closer look at this area, see the press release Flight over canyon-area Hydraotes Chaos from 2014. Chaotic terrain is commonly found near the Martian dichotomy and is especially prevalent in the source regions of ancient outflow valleys. These features may be closely linked to the flooding events that formed the outflow channels.
The flight concludes with a view over the approximately 100-kilometer-wide Da Vinci impact crater. In contrast to the chaotic terrain just passed, the crater floor appears relatively smooth. The large Da Vinci crater is overlain by a younger impact crater with a prominent ejecta blanket – material ejected from the subsurface during the impact.
