Scott, K.M., Tucker, D.S., and McGeehin, J., 2003, Island of Fire in a Sea of Ice - The Growth of Mount Baker volcano and the Fraser Glaciation in the North Cascades: XVI INQUA Congress Program with Abstracts, p. 51
Island of Fire in a Sea of Ice - The Growth of Mount Baker volcano and the Fraser Glaciation in the North Cascades
Late Pleistocene lithic pyroclastic flows, syneruptive lahars, and lavas mark the final stage in construction of the Mt. Baker stratocone. These syneruptive assemblages overlie glacial deposits of the Vashon Stade of the Fraser Glaciation. Correlation with the Vashon, beginning ca. 20,000 14C years BP, is verified by clasts of a distinctive 2-pyroxene Baker andesite. W.E. Hildreth defines the beginning of the volcano's major period of growth at 30,000-40,000 years with K-Ar ages of lavas. The spread of the final volcaniclastic apron over glacial deposits shows that the Cordilleran Ice Sheet (CIS) surrounded the growing volcano from multiple directions, with upstream flow from the west bringing dunite from Twin Sisters Mountain.
Edifice growth was completed during the following Everson Interstade, as what we define as Glacial Lake Baker filled the Baker River valley south of the volcano. Lacustrine deposits are intercalated with Baker tephras and alluvial run outs of syneruptive flows. The Sandy Creek beds are a varved lacustrine sequence transitional above till texturally like clay-rich diamictons of the CIS elsewhere and yield a date of 12,200+/-45 BP. Thus a CIS remnant may have remained around the Baker edifice to near that time.
The Baker edifice was completed before the alpine glaciation of the Younger Dryas or Sumas Stade. Flank soils yield dates of at least 11,020+/-180 BP and include Baker tephra SP, 10,800 BP. The innermost in a sharply defined complex of terminal moraines in the Middle Fork Nooksack River yields these ages: log at the basal contact with Vashon deposits, 10,600+/-40 B.P.; logs 2 m above the base, 10,510+/-50 and 10,520+/-50 PB; log 5 m from the top of the 14 m section. The moraines end by 4.7 km down channel from the modern Deming Glacier, and 3.0 km down channel from the Neoglacial terminus in the Middle Fork.