Sailing stones, sliding rocks, and moving rocks all refer to a geological phenomenon where rocks move in long tracks along a smooth valley floor without human or animal intervention. They have been recorded and studied in a number of places around Racetrack Playa, Death Valley, where the number and length of travel grooves are notable.
These rocks in Death Valley seem to frequently have races. It seems to be a combination of the wind, water and ground movement. Follow the link for more pictures and more info. It really is amazing. http://somentecoisaslegais.com.br/incrivel/pedras-que-andam-sozinhas?fb_action_ids=464093723647163_action_types=og.likes_source=other_multiline_object_map=%7B%22464093723647163%22%3A457711614293649%7D_type_map=%7B%22464093723647163%22%3A%22og.likes%22%7D_ref_map=%5B%5D
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