This image in Athabasca Valles shows lava flows originating from Elysium Mons to the northwest. A Context Camera image shows the lava flowed from the northwest to the southeast, diverting around obstacles as it settled. (The flow is outlined in blue with the flow direction shown in yellow, and the approximate location of the HiRISE image is represented by a white rectangle.)
The lava appears to have flowed smoothly around obstructions, almost like water, forming streamlined islands. In the southern part of this image, a branch of the flow diverts around a small crater, and eventually rejoins the main part of the flow. Irregular-shaped ring structures appear on the northern end and are related to the volcanic activity that formed the flows…. [More at link]