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HOOKSHAPED PATTERN

This is developed when early recumbent to reclined folds (this expression for the comprehension is used here rather than the correct one) are superimposed by later upright folds with subvertical axial planes in a manner so that the axial planes of early folds are folded but their axes or hinges remain unaffected. In other words, the hinges of the two fold sets lie parallel to each other even after the cessation of late folding. In other words, type 3 pattern is developed where amplification direction of late folds lies at high angle to the axial planes of early folds as in type 2 pattern, the difference being that while in type 2 pattern both hinges and axial planes of early folds are folded by later folds, in type 3 pattern, only the axial planes of early folds are folded and there is more or less complete parallelism between early and late fold hinges. The typical pattern of outcrops produced is that of hooks. This hook shaped pattern is common in many orogenic belts. The two photographs that are produced are from the Delhi Orogenic belt, one from Bharatwa and the other from Badnor area. The one that is shown is the type 3 pattern on outcrop scale, the photograph was taken by J G Ramsay in Loch Monar area of NW highlands of Scotland.