Descrizione del progetto
Il mercurio per una comprensione del vulcanismo su larga scala
Le grandi province ignee sono eventi vulcanici su larga scala. Il loro ruolo nel rapido cambiamento globale rimane complesso a causa della mancanza di equivalenti diretti/univoci del vulcanismo nei sedimenti che testimoniano gli eventi. Alcuni recenti studi hanno svelato che il mercurio (Hg) è un promettente marcatore del vulcanismo su larga scala. Tuttavia, manca ancora la vitale comprensione del processo di equivalenza, necessaria per raggiungere il suo pieno potenziale. Il progetto V-ECHO, finanziato dall’UE, esaminerà la possibilità che i «picchi» diffusi di mercurio nei dati geologici rappresentino una prova definitiva di vulcanismo delle grandi province ignee in assenza di lave coeve. Il progetto svilupperà una comprensione del processo per cui le grandi province ignee perturbano il ciclo globale del mercurio e indagherà la loro trasformazione in reperti sedimentari.
Obiettivo
Rapid global change events such as mass extinctions punctuate Earth’s geological history. These have driven life’s evolution, shaping the world today. However, the exact processes that trigger or modulate them remain enigmatic. Episodes of large-scale volcanism, namely large igneous provinces (LIPs), are a prime contender. A major obstacle to unravelling the role of LIPs in rapid global change has been lack of a direct/unique proxy for volcanism in the sediments that record events. Without one, determining LIP occurrence and exact temporal relations is challenging, especially where the rock record of LIPs is incomplete. Recent studies have revealed the huge promise of mercury (Hg) as a marker of large-scale volcanism. However, while Hg-record acquisition is gaining pace, we still lack the vital process understanding of the proxy needed to realize its full potential. V-ECHO will test the overarching hypothesis: widespread mercury ‘spikes’ in the geological record are definitive evidence of LIP volcanism even in the absence of coeval lavas.
V-ECHO will take an integrated and interdisciplinary approach to develop a process understanding of LIP perturbations to the global Hg cycle and how these translate into sedimentary records. It will address key questions on Hg sources (emission from magmas or thermal metamorphism of intruded rocks) and sinks (deposition pathways and sedimentary preservation). It will combine new measurements with novel experimental techniques and explore key differences in the global Hg cycle deep in Earth’s past. V-ECHO will test whether we can ‘sniff out’ the sedimentary echoes of lost LIPs, especially in the Palaeozoic and Neoproterozoic where the LIP record becomes ever sparser. It will explore proposed volcanic triggers for major Earth change events (e.g. oceanic anoxic events, ‘snowball Earths’) in unprecedented ways.
V-ECHO promises a step-change in understanding of environmental impacts of LIP volcanism throughout Earth history.
Campo scientifico
Parole chiave
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-COG - Consolidator GrantIstituzione ospitante
OX1 2JD Oxford
Regno Unito