A "fissure" is a crack or break in something. You might use the word "fissure' to describe a steep-sided canyon, something that looks like a crack in the mountain. You would not use "fissure" to describe the mountain itself.
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It would be more detailed. It would let people know how steep a certain hill/ mountain is.
A mountain is an elevated area of land, higher than a hill, with sloping sides, a plateau is a fairly flat area above surrounding land and a plain is a large, flat area of land usually without trees.
steep snow-covered hill, and a trigger
deep: is down very low such as the ocean is deep steep: high narrow: thin wide: large or fat
A Gorge. Your Welcome!
sugar loaf
A steep-sided hill or mountain that stands alone and is usually smaller than a mesa is called a butte.
Caldera/ crater.
In steep sided, snow covered mountain valleys.
An arete is a mountain ridge that is steep sided and narrow along the ridge.
Gorge
A butte is a steep-sided hill or mountain that stands alone and is usually smaller than a mesa. Its distinct shape is often created by weathering and erosion of surrounding rock layers.
A barranca is a steep-sided gulch or arroyo.
A canyon.
ash and lava
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