Coal Deposits of Raton Coal Field, New Mexico

Charles L. Pillmore

Cretaceous and Tertiary coal-bearing rocks of the Raton coal field underlie about 1,000 sq mi of the New Mexico part of the Raton basin. Although coal has been mined commercially in this field since 1870, the rocks in the Vermejo Formation (Late Cretaceous) and the Raton Formation (Late Cretaceous and Paleocene) still contain more than 1 billion tons of high-quality, medium-to-high-volatile A and B bituminous-rank coking coal. The Vermejo Formation consists mainly of nonmarine sandstone, siltstone, and shale and beds of coal; it ranges in thickness from more than 350 ft in the western part of the field to less than 50 ft along the southeastern margin and is absent east of Raton. The Raton Formation is lithologically similar to the Vermejo and ranges in thickness from more than 1,900 ft in the west-central part to about 1,400 ft near Raton Pass in the eastern part; most of the minable coal beds in the Raton Formation are in the west-central part of the field in the upper two-thirds of the formation. Thickness of coal beds in both formations ranges from coaly streaks to at least 11 ft.

Early mining was concentrated along the eastern and southeastern margins of the coal field in coal beds in the Vermejo Formation. The last of these mines was shut down in 1966 when a mine was opened on the York Canyon coal bed in the upper part of the Raton Formation about 35 mi west of Raton. The shift in mining activity makes feasible the development of several coal beds recently discovered in the western part of the field.

AAPG Search and Discovery Article #91051©2012 AAPG Rocky Mountain Section Meeting, Albuquerque, New Mexico, 23-26 February 1969