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Pre-eruptive storage conditions of the Holocene dacite erupted from Kizimen Volcano, Kamchatka

B. Browne·P. Izbekov·J. Eichelberger·T. Churikova
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Abstract

This study describes an investigation of the pre-eruptive conditions (T, P and fO 2 ) of dacite magma erupted during the KZI cycle (12,000-8400 years ago) of Kizimen Volcano, Kamchatka, the earliest, most voluminous and most explosive eruption cycle in the Kizimen record. Hydrothermal, water-saturated experiments on KZI dacite pumice coupled with titanomagnetite-ilmenite geothermometry calculations require that the KZI dacite existed at a temperature of 823 ?? 20??C and pressures of 125-150 MPa immediately prior to eruption. This estimate corresponds to a lithologic contact between Miocene volcaniclastic rocks and Pliocene-Pleistocene volcanic rocks located at a depth of 5-6 km beneath the Kizimen edifice, which may have facilitated the accumulation of atypically large volumes of gas-rich dacite during the KZI cycle.

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B. Browne, P. Izbekov, J. Eichelberger, T. Churikova. 2010-07-12. Pre-eruptive storage conditions of the Holocene dacite erupted from Kizimen Volcano, Kamchatka. https://doi.org/10.1080/00206810903332413

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