apocalyptic appearance black cloud clouds color colorful colour colourful contrast contrasting dark dark clouds darkening darkness disturbing dramatic dusk evening foreboding formations frightening gray grey layers levels light lighting moody nature rays skies sky storm stormy sunlight threatening weather wild accretions bio-chemical-accretionary-structures cementation columnar cumulative-structures excretions formed forming fossils high-saline-levels lake layered living-fossils living-rocks microbialites microorganisms natural park rock-structure sedimentary-grains shallow-water shaped shapes slow-growth stromatolite stromatoliths structures angry approaching-storm atmosphere atmospheric blue bright cloud-formations early-evening meteorological-phenomenon setting sun shining southern spreading storm-clouds sun sunset abstract background celebrate celebration choral church classical column craftsmanship flute formation group high instrument interior low mathematical mathematics metal mouth music musical orchestra organ pattern pipe pipes pitch prospect religion religious service shape shiny similar sound steel straight tube tubes tune wedding aerial aeroplane airplane behind colored colors coloured colours condensation-trail conditions contrail fine following jet jet-engine-exhaust line moisture streaks streaky textures thin trail trailing vapor vaporish vapour vapourish variations white wispy Australia blue skies blue sky brown central Australia country side distance distant dry expanse flat hills landscape movement moving outback panoramic views plains rocks rural scenery scenic shadows sightseeing speed speeding train sunshine train journey travel travelling undulating vegetation water pipeline window apocalypse backgrounds climate cloudscape cloudy danger destruction disaster downdraft environment fear force gale heaven heavy hurricane mammatus meteorology ominous outdoors overcast power rain scary scene surreal thunderstorm wall wind accumulations art artistic artwork coloring colouring decorative distinctive down edge edges fantastic fantasy forms green lit multicolored multicoloured pointed red stalactites stalagmites subterranean surface surfaces suspended texture unusual UP yellow