Vallis

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  Mountain range

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  Escarpment

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  Rock

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  Chasma

  Chasma is a term used in astrogeology to refer to "a deep, elongated, steep-sided depression". The plural is chasmata. An example is Eos Chasma on Mars. Below are images of some of the major chasmata of Mars. The map shows their relative locations. Parts of the floor of Candor Chasma contains...
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  Linea

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