Numerical modeling outcomes present that the structure of magma plumbing programs between the Earth’s mantle and floor and the way magma evolves by means of these programs play a elementary position within the building and evolution of volcanic edifices. Nevertheless, as a result of inaccessibility of most lively volcanic programs to high-resolution imaging, the detailed morphology of probably the most superficial magma reservoirs and the connection between magma upwelling initiation and eruption dynamics nonetheless should be found.
Topography and tectonics of the ocean flooring (left) and 3D morphology of magmatic lenses beneath the floor (proper) of a phase on the East Pacific Rise. © Marjanovic – CNRS – IPGP
A research printed on September 29 in Science Advances by a global group involving scientists from the CNRS, the Institut de Physique du Globe de Paris and Université Paris Cité presents unprecedented high-resolution seismic photos that make clear the small-scale structure of the community of shallowest magma our bodies, situated beneath an erupting zone of the East Pacific Rise. These photos, the results of a detailed collaboration with trade specialists, which enabled a cutting-edge imaging approach, have been obtained by inverting the waveforms of seismic reflection knowledge acquired throughout a marine analysis cruise performed in 2008.
The research reveals that these lenses, which have been till now modeled as clean our bodies, in actuality current ridges and troughs that are interpreted as zones the place repeat dikes (seams of magma which rise from the reservoir as much as the floor) nucleate. This peculiar morphology is sculpted by the processes of magma recharge from the mantle and magma extraction in the direction of the floor. The recurrence of those processes leaves an imprint, linked to the focus of stresses induced by the topography, which contributes to the nucleation of the dikes and the triggering of the rise of magma in the direction of the floor and extra broadly to the dynamics of subsequent eruptions.
By together with these new ends in the most recent era of three-dimensional numerical fashions, it ought to now be doable to acquire a extra lifelike illustration of volcanic programs which is able to contribute to higher localization of eruptions, and thus to the advance of danger evaluation.
References:
> Insights into dike nucleation and eruption dynamics from high-resolution seismic imaging of magmatic system on the East Pacific Rise, Marjanović et al., Sci. Adv. 9, 2023.
