Event Name : Espenberg South Killeak Maar
|Stop: 40000 || Years BP Tephrochronology || |
|Maar, tuff cone, tuff ring: ||
From Hopkins (1988): "The youngest and most spectacular volcanic features in the Devil Mountain-Cape Espenberg area consist of a group of five maars (shallow, broad, low-rimmed explosion craters formed by eruptions rich in steam)."
"The basin of South Killeak Lake has maximum and minimum diameters of 4.3 and 3.0 kilometers. Steep but vegetated slopes rise from the perimeter of the lake. Concentric ridges, swales, and gullies in a belt one or two kilometers wide delineate ridges that may represent ancient base-surge deposits. Beaches are narrow and on the west shore consist mostly of boulders. Welded scoria are exposed in a ledge on the east side of the lake; little or no exposed lava or ejecta can be found elsewhere on the basin slopes. However a gully 50 meters deep entering the east shore of the lake (Locality 2, Figures 7-2 and 7-3 [in original text]) exposes ejecta generally similar to ejecta from the Devil Mountain Lake maars. Scattered quartz pebbles are larger and less rounded than the redeposited beach pebbles in the Devil Mountain Lake ejecta."
From Beget and others (1996): "...South Killeak Maar is >40,000 years old..."