Exploring the influence of vent location and eruption style on tephra fall hazard from the Okataina Volcanic Centre, New Zealand

摘要: Uncertainties in modelling volcanic hazards are often amplified geographically large systems which have a diverse eruption history that comprises variable styles from many different vent locations. The ~700 km2 Okataina Volcanic Centre (OVC) is caldera complex New Zealand has displayed range of and compositions over its current phase activity (26 ka–present), including one basaltic maar-forming eruption, Plinian nine rhyolitic eruptions. All three these occurred within the past 3.5 ky, any could occur event future eruption. location also unknown. Future vents potentially open areas been activated 26 ky at OVC: Tarawera linear zone (LVZ) (five eruptions), Haroharo LVZ eruptions) or outside LVZs (one eruption). A OVC likely to generate widespread tephra fall loads will cause significant disruption severe socio-economic impacts. Past hazard studies focused on evaluating select locations OVC’s LVZ. Here, we expand upon by for all possible both styles, explore how parameters influence forecasts. Probabilistic model BET_VH advection–diffusion TEPHRA2 were used assess accumulating ≥10 kg m−2 occurring LVZ, other potential caldera. Our results highlight importance considering system, order capture full catalogue analyses (e.g. 11 eruptions versus only five LVZ), as well spatial distribution hazard. Although prominently discussed because recent (1886 ~1315 ad), find estimated likelihood opening (last 5.6 ka) equivalent (<1 % difference) (31.8 compared 32.5 %). Including source analysis allows us extent By multiple areas, present assessment aims reduce bias through incorporating greater variables.