The Matanuska Valley of south-central Alaska contains relatively small but important reserves of coal within the Chickaloon Formation of Early Tertiary age. Identified resources amount to about 90 million metric tons, and hypothetical-resource estimates range to 450 million metric tons. Most of the potentially minable resources are concentrated in the Eska-Moose (Wishbone Hill) and Chickaloon fields. Coals of the Chickaloon Formation formed in paludal swamps . I Clough and G.R. Eakins of the Alaska Division of Geological and Geophysical Surveys. M.A. Belowich assisted the author during field investigations and office/laboratory research.13 km wide, 80 km l ~r . 7 , 3r.d has an area of at least 5 0 0 km , and lies 8 0 to 1 6 0 km nort?:?ast of Anchorage. Its western end is 40 to 80 km northeast of tidewater, and the center of the coal field is 240 km from Seward by rail. The general trend of the coal field is N. 70°E, and it is located at 61' north latitude (Apell, 1944;Kreig and Associates, 1983).