Profitis Ilias is formed of uplifted fault blocks themselves a product of the Hellenide orogeny which produced a stack of Alpine nappes of Mesozoic age. These are part of the Pindos-Olonos series of low-grade metamorphic limestone sediments. The mountain overlooks Middle Miocene-Pleistocene sedimentary basins. Sudden topographic variations and land instabilities are due to a multitude of thrust faults. Ophiolites, usually gabbro occur.