Event Name : Black Peak CFE
|Start: 4700 (± 100 Years) || Years BP C-14 (raw) || |
|Stop: 3660 (± 90 Years) || Years BP C-14 (raw) || |
|Pyroclastic flow, surge, or nuee ardente: ||
|MaxVEI: ||6 ||
|Eruption Product: || andesite ||
From Miller and Smith (1987): "Black Peak is the middle and smallest (3 km diameter) of the three neighboring calderas. Ash-flow tuffs as much as 100 m thick are exposed in two large drainages on the west side of the volcano The tuffs appear to have been more passively emplaced as compared to those from the neighboring calderas, and they have a large air-fall component. In spite of the caldera’s small diameter, the apparent widespread distribution of climactic air fall and thickness of the ash-flow tuffs suggest a bulk eruption volume of >10 km cubed."
"Attempts to find charcoal in, or organic material directly beneath, the ash-flow tuff were unsuccessful. However, organic material from beneath a distinctive coarse air-fall tuff, assumed to represent the climactic caldera-forming eruption of Black Peak, yielded 14C ages of 4470+/-200, 4170+/-90, and 4700+/-100 yr (samples 12-14, Table 1 [in original text]). These are maximum ages; sample 17, dated at 3660+/-90 B.P. is a minimum age from organic material overlying the climactic air fall. These dates are consistent with the tephra stratigraphy and suggest a date somewhere between 3660 and 4170-4700 B.P. for the caldera-forming eruption of Black Peak."
From Waythomas (2015): "Thick pyroclastic deposits in the vicinity of the volcano and extensive ash fallout that formed a prominent regional tephra layer."
The Global database on large magnitude explosive volcanic eruptions (LaMEVE; 2017) reports a magnitude of 6.5, bulk eruptive volume of 30 cubic km and a dense rock equivalent eruptive volume of 12 cubic km for the eruption.