Adagdak reported activity

Event Name : Adagdak Younger Cone

Start: 1020000 (± 150000 Years)

Years BP Ar/Ar

Lava flow:
Lahar, debris-flow, or mudflow:

Eruption Type:	Effusive
Eruption Product:	andesite
Chem	Yes
Other	mafic

Description: From Baten (2002): "Mt. Adagdak (650 m asl) was built from three stages of volcanism (Figure 1.5 [in original text])."

"The second stage of volcanism resulted in the formation of two composite cones. The older cone formed on the southern portion of the remnant shield and the younger cone formed on the eroded northern flank of the older composite cone (Coats, 1956). Both cones are primarily andesitic in composition."

"...the younger cone yields a date of 1.02 +/- 0.15 Ma..."

From Meyers and Frost (1994): "A renewed phase of volcanism produced a younger composite cone on the northern flank of the older, eroded composite cone (Fig. 2 [in original text])."

From Coats (1956): "Younger composite cone-A sequence of mudflows consisting largely of fragments of hornblende andesite, capped by two thin hornblende andesite lava flows, makes up the western flanks of Mount Adagdak. These rocks represent a younger cone built after the sea had partly eroded the older composite cone."