The ~AD1315 Tarawera and Waiotapu eruptions, New Zealand: contemporaneous rhyolite and hydrothermal eruptions driven by an arrested basalt dike system?

摘要: A series of large hydrothermal eruptions occurred across the Waiotapu geothermal field at about same (prehistoric) time as ~AD1315 “Kaharoa” rhyolite magmatic from Tarawera volcano vents, 10–20 km distant. Triggering was previously attributed to displacement adjacent Ngapouri Fault. The Kaharoa are now recognised primed and triggered by multiple basalt intrusions beneath volcano. ~1000 t/day pulse CO2 gas is recorded alteration mineralogy fluid inclusions in drill core samples wells. This most readily sourced intruded depth, although not precisely dated, it appears be associated with eruptions. We infer that were intrusion arrested dike system drove Tarawera. likely similar depth generated a 17 km-long fissure formed region AD1886. Fault ruptures area association both AD1886 considered result, rather than cause, processes.