Black Rapids Glacier, E Alaska, Alaska Range, at foot of Mt. Hayes; 25 mi/40 km long, 2 mi/3.2 km wide; 63°28'N 146°W. Elev. 400 ft/122 m at face. In 1936, due to undetermined disturbance, glacier moved forward 5 mi/8 km in 6 months; it is a surge glacier.