Structural geology term for a fold with younger layers closer to the center of the structure
In
structural geology, a syncline is a
fold with younger layers closer to the center of the structure, whereas an
anticline is the inverse of a syncline. A synclinorium (plural synclinoriums or synclinoria) is a large syncline with superimposed smaller folds.[1] Synclines are typically a downward fold (synform), termed a synformal syncline (i.e. a trough), but synclines that point upwards can be found when strata have been overturned and folded (an antiformal syncline).
Characteristics
On a geologic map, synclines are recognized as a sequence of
rocklayers, with the youngest at the fold's center or hinge and with a reverse sequence of the same rock layers on the opposite side of the hinge. If the fold pattern is circular or elongate, the structure is a
basin. Folds typically form during
crustal deformation as the result of compression that accompanies
orogenic mountain building.