From abstract: The Rosebud coal field, named from Rosebud Creek and the village of Rosebud, includes an area of about 1,050 square miles and forms a very small part of the subbituminous and lignite coal fields of eastern Montana and Wyoming and the western part of the Dakotas. It is an irregularly bounded tract lying south of the Yellowstone River in eastern Rosebud County and western Custer County and measures 50 miles from east to west and 28 miles from north to south. It adjoins the Forsyth coal field, on the west, the Ashland coal field, on the south, and the Miles City coal field, in part, on the north.