Deep Magma Transport Control on the Size and Evolution of Explosive Volcanic Eruptions

Abstract

Explosive eruptions are the surface manifestation of dynamics that involve transfer of magma from the underground regions of magma accumulation. Evidence of the involvement of compositionally different magmas from different reservoirs is continuously increasing to countless cases. Yet, models of eruption dynamics consider only the uppermost portion of the plumbing system, neglecting connections to deeper regions of magma storage. Here we show that the extent and efficiency of the interconnections between different magma storage regions largely control the size of the eruptions, their evolution, the causes of their termination, and ultimately their impact on the surrounding environment. Our numerical simulations first reproduce the magnitude-intensity relationship observed for explosive eruptions on Earth and explain the observed variable evolutions of eruption mass flow rates. Because deep magmatic interconnections are largely inaccessible to present-day imaging capabilities, our results motivate the need to better image and characterize extant magma bodies.

Seismic tremor reveals active trans-crustal magmatic system beneath Kamchatka volcanoes

“…Geological evidence accumulated during the past three decades, however, spawned the image of trans-crustal systems where mixtures of melt, crystals, and volatiles are heterogeneously distributed with intermittent vertical connectivity ( 1 , 2 ). The interaction between shallow reservoirs and deeper storage might affect the size and evolution of eruptions ( 3 ). How these elaborate systems get built over time and how they contribute in individual eruptive events remain poorly understood.…”

“…),(3), and (4) to classify the retained detections in three main groups: tremors, earthquakes, and "intermediate." Line expressions are (1) ~  tremor = − 5 × (NRF − 0.3 ) + 1.8 ; (2) ~  earthquake = − 0.63 × (NRF − 0.05 ) + 1.1 ; (3) ts tremor = 1.5 × (NRF − 0.33) − 0.1; and (4) ts earthquake = − 0.03 × (NRF − 0.05) + 0.164.…”

Modeling the Viscosity of Anhydrous and Hydrous Volcanic Melts

“…The shear viscosity () of naturally occurring aluminosilicate (i.e., volcanic) melts controls their transport at depth, the way they evolve to a crystal‐ and/or bubble‐bearing system (i.e., magma) and, therefore, multiphase of magma. The viscosity of a magma also regulates its ascent rate to the Earth's surface, the rheological response to deformation, the degassing and outgassing regime, and determines the style of volcanic eruptions (Cassidy et al., 2018; Colucci & Papale, 2021; Di Genova, Kolzenburg, et al., 2017; Dingwell, 1996; Gonnermann & Manga, 2007; Papale, 1999).…”

Dynamics of Magma Chamber Replenishment Under Buoyancy and Pressure Forces

“…Long lifetime to such shallow magmatic bodies, much in excess of estimated conductive cooling lifetimes, is provided by repeated magma injection events (Marsh, 2015) which add mass, heat, and volatiles, thus contrasting shallow‐level cooling and degassing. Events of new injection at shallow level by deeper, chemically and physically distinct magma are often recognized to have shortly preceded the occurrence of a volcanic eruption (Colucci & Papale, 2021, and references therein). The dynamics associated with magma injection at shallow level are the subject of this work, specifically focusing on the roles of natural and forced convection, represented within magmatic systems by the buoyant and overpressurized systems addressed in this work, respectively.…”