Geologically the Arbuckles are an elongate anticline structure with an orientation or strike of west-northwest. The core of the structure consists of Proterozoic extrusive and intrusive rocks, the Colbert rhyolite porphyry and the Tishomingo granite (age dated at 1374 Ma),[3] which are overlain and flanked by early Paleozoic limestones and sandstones that are very steeply dipping to near vertical in orientation. Pennsylvanian to Permian conglomerates were deposited after the orogenic buckling had uplifted and deformed the older strata.