#oceanic_abyss__oceanicabys__trench__deep  a long steep-sided depression in the ocean floor
  supertype:  #natural_depression__naturaldepression__depression  a sunken or depressed geological formation
  subtype:  #Atacama_Trench  a depression the floor of the Pacific Ocean off the coast of Chile
  subtype:  #Bougainville_Trench  a depression in the floor of the Pacific Ocean between New Guinea and the Solomon Islands
  subtype:  #Japan_Trench  a depression in the floor of the Pacific Ocean northeast of Japan that reaches depths of 30,000 feet
  subtype:  #Nares_Deep  a depression in the floor of the Atlantic Ocean north of Haiti and Puerto Rico

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