- The Umatilla Indian Reservation is an Indian reservation in the Pacific Northwest of the United States. It was created by The Treaty of 9 June 1855 between the United States and members of the Walla, Cayuse, and Umatilla tribes. It lies in northeastern Oregon, east of Pendleton. The reservation is mostly in Umatilla County, with a very small part extending south into Union County. It is managed by the three Confederated Tribes of the Umatilla Indian Reservation.
- Mariana Plate (Wikipedia)
The Mariana Plate is a micro tectonic plate located west of the Mariana Trench which forms the basement of the Mariana Islands which form part of the Izu–Bonin–Mariana Arc. It is separated from the Philippine Sea Plate to the west by a divergent boundary with numerous transform fault offsets. The boundary between the Mariana and the Pacific Plate to the east is a subduction zone with the Pacific Plate subducting beneath the Mariana. This eastern subduction is divided into the Mariana Trench, which forms the southeastern boundary, and the Izu–Ogasawara Trench the northeastern boundary. The subduction plate motion is responsible for the shape of the Mariana plate and back arc.