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
Angola Basin by gravity spreading and increased sediment loading, major factors which act upon the Angola Basin. In the basin this tectonic mechanism is attributed to three periods of high strain that occurred at approximately 96, 28, and 10 million years ago, and the most recent high strain activity is still ongoing. These high strain rates lasted anywhere from 15 to 36 million years while rafting itself lasted from 7-10 million years. The formation of the Angola Basin can be divided into three phases of rifting which took place from approximately 145-113 million years ago from the Jurassic to the Cretaceous. Initial