Related by context. Frequent words. (Click for all words.) 59 Gusev crater 57 rock outcrop 56 lava tubes 56 Valles Marineris 55 scalloped edges 54 stalactite 54 subparallel 54 rock outcrops 54 lunar craters 54 basaltic 54 gable roof 54 plutons 53 graben 53 ellipse 53 erosional 53 promontories 53 cuboid 53 granite cliffs 52 pentagonal 52 equilateral triangle 52 concentric rings 52 knolls 52 geometric pattern 52 earthen mounds 52 clasts 52 whorls 52 northerly trending 51 Durrington Walls 51 gently curved 51 polar craters 51 stockwork veining 51 rectangular 51 tonalite 51 lava tube 51 boomerang shaped 51 tetrahedron 51 braincase 51 pilasters 51 trapezoid shaped 51 lunar soil 50 wavelike 50 hexagonal 50 scarps 50 cavelike 50 heavily cratered 50 palisade 50 snail shells 50 basalt rock 50 varying heights 50 talus 50 Endurance Crater 50 igneous rocks 50 vertical shafts 50 roof overhangs 50 latitudinal 50 coquina 50 landform 50 geodesic 50 irregular shapes 50 irregularly shaped 50 volcanic rock 50 clapboard siding 50 termite mounds 49 lattice 49 Martian landscape 49 en echelon 49 latticed 49 semicircular 49 Mineralization occurs 49 pyroclastic 49 moonlets 49 gossanous 49 paved walkway 49 polar vortex 49 cascading waterfall 49 Olympus Mons 49 sawtooth 49 Doric columns 49 andesitic 49 mosaic floors 49 tuffs 49 breccia zones 49 mosaic tile 49 brick walkway 49 landforms 49 hydrothermal breccia 49 rock outcroppings 49 kiva 49 foliated 48 sandstone formations 48 indentations 48 scrollwork 48 chalcedony 48 lobed 48 transept 48 flagstones 48 pebbled 48 terra cotta tiles 48 boxlike 48 weakly mineralized 48 cruciform