The Roosevelt River is a Brazilian river, a tributary of the Aripuanã River about 760 km (470 mi) in length.
Colonel Theodore Roosevelt and Colonel Rondon
Image: Through the Brazilian Wilderness by Theodore Roosevelt (1925) (page 373 crop)
Aripuanã River is a river in the Mato Grosso and Amazonas states in north-western Brazil. It is a tributary of the Madeira River in the Amazon Basin. The town of Novo Aripuanã is located on its banks where it merges into the Madeira River. The town of Aripuanã is also on its banks, but on the upper (southern) section of the river.
The confluence of the Madeira River (brown) and Aripuanã River (dark) near the town of Novo Aripuanã. Despite its color on this photo, Aripuanã is clearwater rather than a blackwater.