From Miller and others (1998): "Mount Dutton is a small snow- and ice-covered calc-alkaline volcanic center with an approximate diameter of 5 km (not including the isolated large intra-canyon
lava flow 5 km southwest of the summit) and an estimated volume of 7-15 cubic km. The
volcano is built on an east-sloping basement of hydrothermally altered Tertiary volcanic rocks (Kennedy and Waldron, 1955).
"The volcano consists of a central multiple
dome complex (Davies and others, 1988) in which successive domes shouldered aside earlier domes and the enclosing cone-building volcanic rocks. Some hydrothermal alteration occurs along vertical contacts between adjacent domes. The dome-building activity and associated collapse has caused extensive destruction of cone-building
lava flows and, to a lesser extent the domes themselves. This has resulted in the massive, thick-bedded debris flows 100-200 m thick that surround and
mantle the central dome complex.
"A headwall
scarp about 300 m high and dipping to the northwest about 45 degrees forms the west side of the summit. Debris avalanches from this and lower areas moved down either side of the east-west oriented range crest. The resulting
avalanche deposits include blocks up to 5 m in diameter and are characterized by hummocky topography and small closed depressions. The avalanche deposits cover a total area of about 11.4 square km and have an estimated volume of about 0.17 cubic km.
"Only slightly dissected debris flows and
pyroclastic flows occur on the east flank of the volcano. Two flank-domes occur 3.5 km north-northeast of the summit of Mount Dutton at an elevation of 520 m. These non-glaciated flank domes are assumed to represent
Holocene eruptions. Most, if not all, of the avalanche and debris flows that mantle the volcano's flanks are also Holocene in age."