ABSTRACT

Considered evidences show that stylolite formation succeeded rock induration in limestones of many ages from Middle East localities. Observations of B. M. Shaub, allegedly proving origin of some North American stylolites prior to consolidation, are examined and pronounced inconclusive as to relative times of stylolite formation and rock hardening.

Existing stylolite seams may facilitate subsurface fluid movement, thus affecting oil migration, accumulation and production. Stylolite development in limestones, like compaction in shales, causes expression of part of the contained fluids: but such expression occurs late in rock-history, not predominantly at an early stage as in the case of normal compaction. Stylolite formation entails local supersaturation of the solvent water, and consequent local redeposition, thus reproducing in many limestones the same type of fluid expression as is occasioned in some sandstones by cementation related to grain interpenetration.