In areas of superposed (interference) folding producing dome-and-basin patterns, two fold generations with differently oriented axial planes/hinges are present; hinge-line orientations help distinguish early (refolded, more variably oriented) from late (consistently oriented) folds.
The late folds are specified to have vertical E-W trending axial planes, so late-fold hinges should plunge shallowly and trend close to E-W (090/270). A...
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