Uncertainty Quantification of Eruption Source Parameters Estimated From Tephra Fall Deposits

Abstract

Uncertainty quantification (UQ) in eruption source parameters, like tephra volume, plume height, and umbrella cloud radius, is a challenge for volcano scientists because tephra deposits are often sparsely sampled due to burial, erosion, and related factors. We find that UQ is improved by coupling an advection‐diffusion model with two Bayesian inversion approaches: (a) a robust but computationally expensive Generalized Likelihood Uncertainty Estimation algorithm, and (b) a more approximate but inexpensive parameter estimation algorithm combined with first‐order, second‐moment uncertainty estimation. We apply the two inversion methods to one sparsely sampled tephra fall unit from the 2070 BP El Misti (Peru) eruption and obtain: Tephra mass 0.78–1.4 × 1011 kg; umbrella cloud radius 4.5–16.5 km, and plume height 8–35 km (95% confidence intervals). These broad ranges demonstrate the significance of UQ for eruption classification based on mapped deposits, which has implications for hazard management.

Gathering insights into volcanic risk from Auckland to the Andes, Antilles, and Arabia: an unexpected journey to professorship in volcanology

“…Since my doctoral work in the Andes, my research has diversified to encompass a wide range of projects in numerous volcanic settings in the broad area of applied volcanology. For example, in the context of large, intermediate to silicic systems my recent PhD students have worked on exploring how the characteristics and distribution of tephra deposits can constrain numerical tephra hazard models (Constantinescu et al, 2021;Constantinescu et al, 2022), how hydrothermal alteration of rocks affects shallow plumbing systems and edifice stability (Kanakiya et al, 2021a;Kanakiya et al, 2021b;Kanakiya et al, 2022), and how pasture can be rehabilitated following large tephra falls (Sivarajan et al, 2020). A current student, Annahlise Hall, is exploring the explosive eruption history and hazards of the Tongan Volcanic Arc.…”

Reconstructing the Belbaşhanı Pumice Plinian eruption, Hasandağ Volcano, Turkey

“…The magnitude of the Belbaşhanı Pumice eruption has been estimated using only the preserved proximal deposits due to this kind unconsolidated, old fallout deposit (including most of the distal deposits) is susceptible to remobilization by rains and other atmospheric events. However, taking into account (1) the eroded deposits, (2) the decay length scale of the deposit thinning (Bonadonna and Costa 2013), and (3) other uncertainties associated with the used methods (e.g., Bonadonna et al 2015;Primerano et al 2021;Marzocchi et al 2021;Constantinescu et al 2022), the pyroclastic deposit volume is estimated to range from 0.5 to 8 km 3 (with a mean value of ~ 2 km 3 ). This corresponds to a Dense Rock Equivalent (DRE; or magma volume) of 0.26-4.16 km 3 (mean value of ~ 1 km 3 ) considering a density of silicarich magmas of 2400 kg/m 3 (Bonadonna et al 2015).…”

A New Radar‐Based Statistical Model to Quantify Mass Eruption Rate of Volcanic Plumes

“…Various geophysical strategies for the determination of H TP and Q M have been developed, such as the data integration from different sensors with field measurement analysis (e.g., Bonadonna et al., 2011; Corradini et al., 2016; Freret‐Lorgeril et al., 2021; Mereu et al., 2022; Poret et al., 2018). In fact, the Eruptive Source Parameters can be either based on tephra‐fallout deposits (e.g., Carey & Sparks, 1986; Constantinescu et al., 2022; Pyle, 1989; Rossi et al., 2019) or on both ground‐based and satellite sensors (e.g., Aiuppa et al., 2015; Dubuisson et al., 2014; Schellenberg et al., 2019; Wood et al., 2019).…”