Amazonis has become the primary focus of modern research efforts both because of its geological composition and because of its relative youth compared to other Martian regions, which are often hundreds of millions of years older. Hartman writes that the plain closely resembles Iceland's surface, with its "strange cobweb-like networks of ridges and crags both planets, divide smoother areas into a pattern something like fragments of a broken plate." Both land masses' shapes have been formed by lava flows from volcanic eruptions, causing both surfaces to be covered by a thick layer of hardened lava. Findings from aerial footage of both Amazonis and Iceland have shown nearly identical terrain patterns, signifying the comparative ages of the two regions.