Upward mantle flow from novel seismic observations

Informations projet

UPFLOW

N° de convention de subvention: 101001601

DOI

10.3030/101001601

Date de signature de la CE 24 Mars 2021

Date de début 1 Avril 2021

Date de fin 30 Septembre 2027

Financé au titre de

• EXCELLENT SCIENCE - European Research Council (ERC)

Coût total

€ 2 843 038,00

Contribution de l’UE

€ 2 843 038,00

Coordonné par

UNIVERSITY COLLEGE LONDON
United Kingdom

Periodic Reporting for period 3 - UPFLOW (Upward mantle flow from novel seismic observations)

Période du rapport: 2024-04-01 au 2025-09-30

Résumé du contexte et des objectifs généraux du projet

+ What is the problem/issue being addressed?

The UPFLOW project focuses on mapping upward flow in the Earth's mantle (down to ~2,800 km beneath our feet), which is currently poorly understood, yet it is crucial to understand the evolution and dynamical behaviour of our planet over millions of years.

+ Why is it important for society?

Mid-plate deep upward mantle flow is key to return volatiles to the atmosphere and to produce Earth’s largest melting events extending through hundreds of thousands kms, which coincide with major extinctions and changes in the geodynamo. Without knowing upward flow, we cannot understand global mantle flow and directly link the Earth’s interior with the surface. However, mid-plate upward flow is an outstanding challenge because it cannot be explained by plate tectonics and is poorly constrained.

+ What are the overall objectives?

Similar to medical imaging of the human body, seismic data are used to build images of the Earth’s interior, bringing crucial information about deep Earth processes, but the current data coverage of upward flow and seismic resolution are limited.
The goal of the UPFLOW project is to develop an entirely new high-resolution seismic imaging approach and to collect novel seismic data, which will be used to constrain upward flow in the Earth's mantle in unprecedented detail.

Travail effectué depuis le début du projet jusqu’à la fin de la période considérée dans le rapport et principaux résultats atteints jusqu’à présent

+ April-July 2021: preparation of the 2021 UPFLOW marine expedition in the Azores-Madeira-Canary islands region
+ July-August 2021: UPFLOW marine expedition whereby we deployed 50 ocean bottom seismometers in the Azores-Madeira-Canary islands region (mid-Atlantic region)
+ Sept 2021-Sept 2023: development and refinement of techniques to measure and use seismic wave amplitudes for high-resolution imaging of the subsurface, and for optimal observable design
+ Sept 2021-Sept 2023: development of new accelerated Monte Carlo inversion algorithms with uncertainty quantification for enhanced high-resolution imaging of the subsurface
+ Sept 2021-Sept 2023: development of quantitative, integrated seismological and geodynamical interpretations towards an enhanced understanding of mantle upwelling
+ Sept 2021-Sept 2023: development of novel statistical approaches for the quantitative, objective interpretation of seismic images
+ Jan 2022-August 2022: preparation of the 2022 UPFLOW marine expedition in the Azores-Madeira-Canary islands region
+ Aug-Sept 2022: UPFLOW marine expedition whereby we recovered 49 ocean bottom seismometers in the Azores-Madeira-Canary islands region (mid-Atlantic region)
+ Sept 2022-Sept 2023: quality-control and analysis of data from 2021-2022 UPFLOW expeditions
+ Sept 2022-Sept 2023: determination of clock skew curves associated with UPFLOW's data for timing corrections
+ Nov 2022-May 2023: analysis of UPFLOW data with relation to the 2022 seismic crisis in Sao Jorge island

Progrès au-delà de l’état des connaissances et impact potentiel prévu (y compris l’impact socio-économique et les conséquences sociétales plus larges du projet jusqu’à présent)

+ The UPFLOW data show higher completeness and quality than in previous amphibious experiments with similar equipment. It is the largest and longest dataset of ocean bottom seismometer recordings obtained in the Atlantic ocean so far. We expect to use these data to build a wide range of higher resolution seismic images both at global and regional scales
+ Using land data complementary to UPFLOW data, we performed an exclusive seismoacoustic detection and characterization of an unseen and unheard fireball over the North Atlantic
+ Using land data complementary to UPFLOW data, we mapped anisotropy (the direction of seismic wave speed) in the Madeira-Canary islands region, which provides key information for mapping mantle flow in the region
+ We developed a first version of an algorithm that performs accelerated Monte Carlo inversions of seismic data for global subsurface structure imaging at the global scale. We expect to expand this algorithm to incorporate a wider range of data and of physical parameters until the end of the project.
+We published several initial results further exploring our algorithms for measuring and inverting seismic amplitude data, including the construction of a new crustal model of the Western U.S. and new constraints on ice properties in Greenland
+We published a new framework for combined seismological and geodynamical analyses and interpretation
+ We published novel statistical analyses of seismoc tomography images

Map of the UPFLOW 2021-22 expeditions