From Reed and others (1992)
[1]: "The volcano, located some 175 km southwest of Anchorage, lies in the 94-km-long interval between Redoubt and Spurr volcanoes. * * * The Double Glacier Volcano is exposed as a 2.3-km-long, northwest-trending oval-shaped nunatak surrounded by the Double Glacier. The highest part of the 1.67 km square nunatak is about 430 m above the glacier surface. Although glacial erratics have not been found on the top of the nunatak, it seems likely that the nunatak was covered by ice during one or more of the major glacial events of the Cook Inlet region as described by Schmoll and Yehle (1986)
[2].
"Nearby outcrops of basement rock apparently limit the maximum diameter of the volcano to about 3.5 km. A rough estimate of the original volume of volcanic rocks, assuming a cylindrical shape with a diameter of 2.3-3.5 km and a height of 500 m above the present ice surface, is 2-4.8 cubic km. The volume of a cone of the same dimensions would be about 07.-1.6 cubic km. These volumes suggest that DGV is small in comparison to most other Quaternary volcanoes in the Cook Inlet segment which have volumes that range from 15 to 50 cubic km
[3]."
“Available K-Ar ages indicate that DGV [Double Glacier Volcano] was active 600-900 ka.”