Bering Sea volcanic belt 

(late Tertiary and Quaternary) 

(Bering Sea, Seward Peninsula, and Southwestern Alaska, unit QTvm)

Consists chiefly of voluminous, highly alkalic and olivine tholeiite basalt flows, cones, and maars mostly 
of Holocene to 6 Ma age (Moll-Stalcup, 1990, 1994). Includes widespread alkalic basalt flows, cinder 
cones, plugs and maar craters on Seward Peninsula of Holocene to 28 Ma age. Contains local analcime- or 
nepheline-bearing basanite or nephelinite flows. Unit displays high alkali and low silica compositional 
trends. Occurs in west-central Alaska and adjacent offshore islands. Overlies Seward, Angayucham, 
Koyukuk, and adjacent terranes. For paleomagnetic determinations, extrusive volcanic rocks sampled on 
two Bering Sea islands (Pribilof and Nunivak Islands), with ages of less than 2 and 6 Ma, respectively, 
show no displacements. REFERENCES: Hoare and others, 1968; Moll-Stalcup, 1990, 1994; Moll-Stalcup 
and others, 1994