FOLD MECHANISMS AND DISHARMONY IN "ZEUS" ANTICLINE, MT. LYKAION, PELOPONESSOS, GREECE

In 2^nd century BCE, Pausanias observed that Arcadians claim the birth cave of Zeus is not on the island of Crete but instead is on Mt. Lykaion (Peloponessos). A candidate for this mythical cave is a rock shelter occupying a saddle-shaped bedding-dilation zone in the hinge of a huge upright symmetrical chevron anticline at Cretea, which is adjacent to the Sanctuary of Zeus, Mt. Lykaion. A normal profile view of this anticline is exposed on a steep mountain flank ~300 m high; the rock shelter is halfway up. At the entrance to the rock shelter is a 2-story limestone-block outpost built in the early 19^th century during the Greek War of Independence as a cave of refuge. The dilational zone (~15 m high) occurs approximately 30 m above the stratigraphic contact between two major Upper Cretaceous limestone formations of the Pindos Group: Thin Platy Limestone Beds (TPLB), which folded primarily through flexural-slip mechanisms; and (above it) Thick White Limestone Beds (TWLB), which responded to folding through buckling, tectonic pressure-dissolution, flexural-slip folding, and flexural-slip duplexing. The deformation mechanisms supported by TWLB appear to be influenced by the penetrative presence of large-scale primary (concordant) stylolitization, which imposes frictional resistance to ease of bedding-plane slip. Bedding as expressed in outcrop proves to be more of a pseudo-bedding, which I call stylobedding.

Deformation mechanisms that were active within TWLB are particularly well displayed because of apparent increased layer-parallel shortening produced where the upright chevron anticline distorts coaxially and disharmonically into a strongly overturned to recumbent anticline, produced by out-of-the-syncline flow from an adjacent isoclinal overturned syncline. The overturned limb is marked not simply by conventional buckle folds and parasitic folds, but through flexural-slip duplexes, stylo-thrusts at acute angles to bedding, and stubby tectonic stylolites perfectly perpendicular to stylobedding and truncated at the tops and bottoms of the discrete layers in which they reside.

The structural geology of this anticline, its disharmonic expressions, and the elegance of deformation mechanisms, live up to expectations for the birthplace of a god.