Ochoco Mountains made of rocks from the Permian, Triassic, and Jurassic periods (300 to 200 million years old) that were transported by the Pacific Plate and accreted in the late Mesozoic era (about 100 million years ago) as part of a vast shallow sea, then slowly uplifted by volcanic eruptions during the Eocene epoch (50 to 37 million years ago) to form the Clarno Formation. From 37 to 17 million years ago, eruptions in the western Cascade Range spread ash across eastern Oregon, forming the John Day Formation. From 17 to 14 million years ago, major volcanic eruptions covered much of the
Verdon Gorge the Triassic period, the French region of Provence subsided and was covered by the sea, leaving thick layers of various limestone deposits. Several million years later, with the arrival of the Jurassic period, the area was covered by a warm shallow sea, which allowed the growth of various Corals. The Cretaceous period saw what is now Basse Provence being raised and the sea reaching the current location of the Alps, which were themselves erected during the tertiary era. As a result of the large-scale geological activity, many of the Jurassic limestone deposits fractured, forming relief with valleys and other such