Related by context. Frequent words. (Click for all words.) 65 basalt rock 63 sandstone formations 63 granite cliffs 62 lichen covered 62 rocky ledges 62 Gusev crater 61 salt crystals 60 granite boulders 60 clasts 59 stalactite 59 limestone formations 59 rock outcrops 59 lava tubes 58 escarpments 58 rugged cliffs 58 grassy meadows 58 basalt 58 igneous rocks 57 sandstone cliffs 57 loess 57 igneous rock 57 Valles Marineris 57 rock outcrop 57 volcanic rock 56 tonalite 56 greenish brown 56 rocky outcrops 56 steep ravines 56 knolls 56 tuffs 56 calcareous 56 towering cliffs 56 deep gorges 56 volcanic peaks 55 volcanic crater 55 volcanic cones 55 volcanic cone 55 promontories 55 extinct volcanoes 55 erosional 55 grassy plains 55 basaltic 55 cascading waterfall 55 mudstones 54 greywacke 54 craggy peaks 54 snail shells 54 hardened lava 54 andesitic 54 granite boulder 54 outcroppings 54 landform 54 manganese oxide 54 ridges 54 coquina 54 powdery sand 54 granitic rocks 54 metamorphic rocks 53 boulder strewn 53 Quartzite 53 grassy slopes 53 steam vents 53 landforms 53 rock outcroppings 53 alternating layers 53 ocotillo 53 boulders 53 quartz carbonate veins 53 mudstone 53 lunar soil 53 pine oak 53 moraines 53 foliated 53 termite mounds 53 limestone cave 53 bamboo groves 53 talus 53 sedimentary rock 52 aragonite 52 Namib Desert 52 waxy substance 52 stromatolites 52 goethite 52 grassy meadow 52 calcite 52 rocks 52 polar vortex 52 basalts 52 granite pillars 52 evergreen forests 52 gently undulating 52 tidal basin 52 limestone 52 lavas 52 pyroclastic 52 sandstone 52 gently curved 52 graben 52 craggy cliffs 52 Teton Range 52 lakebed