At face value, what do these features (cross-bedding and gypsum crystals) suggest about depositional environments on Mars in the past?

Answer 1

The occurrence of both cross-bedding and gypsum deposits are indicative of past water on Mars. Cross-bedding is formed by flowing water, carrying sediments. As suspended sediment drops over the lee side of a slope, it is deposited resulting in "tilted" layers. Gypsum is an evaporite mineral that forms when sea water evaporates.