compare the appearance of fold mountain and fault block moun

Fold mountains are formed mainly due to the effects of folding on layers within the upper part of the Earth's crust. Fault-block or fault mountains are formed by the earth's crust being stretched and extended by tensional forces. They are produced when normal (near vertical) faults fracture a section of continental crust. Vertical motion of the resulting blocks, sometimes accompanied by tilting, can then lead to high escarpments. They are generally formed in the less-deformed areas peripheral to areas strongly affected by thrust tectonics.

Fold mountains are found in the foreland region where a major mechanically weak decollement horizon is present. The frontal thrust (or thrusts) propagate(s) a long distance along this horizon and subsequent movement on the thrust can give rise to a sequence of folds as the hanging wall of the thrust effectively crumples. The anticlinal crests may be high enough to form mountains. Fault-block or fault mountains’ Tilted blocks are common in the Basin and Range region of the western United States . Level blocks lead to the horst and graben terrain seen in northern Europe .

Most fold mountains are likely to be relatively young in geological terms as they will start to be eroded as soon as they are formed Fault block mountains commonly accompany rifting, another indicator of tensional tectonic forces. Block mountains can also be referred to as a horst. It is a steep-sided mountain, formed where a block of the earth's crust has been squeezed upward between two parallel fault lines. Two types of block mountains are lifted and tilted. Lifted type block mountains have two steep sides exposing both sides scarps. Tilted type block mountains have one gently sloping side and one steep side with an exposed scarp.
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