Definition: In geology, a "preglenoidal" structure is a type of rock formation that has been formed by the compression and folding of rocks under pressure. It is characterized by the presence of large-scale folds in the surface of the rock, which are usually associated with fault zones or other geological features. These structures can range from small depressions to massive blocks of rock that reach several hundred meters in height. The term "preglenoidal" refers to a type of rock formation where the compression and