Magmatic pulse driven by sea-level changes associated with the Messinian salinity crisis

Area of Science:

• Geosciences
• Paleoclimatology
• Volcanology

Background:

• The Messinian salinity crisis (5-6 million years ago) transformed the Mediterranean into a salt basin, with debated sea-level changes.
• Evaporite deposits and erosional surfaces suggest either deep- or shallow-marine conditions, or subaerial exposure.

Purpose of the Study:

• To investigate the link between kilometer-scale sea-level fluctuations during the Messinian salinity crisis and pan-Mediterranean magmatism.
• To test the hypothesis that lithospheric unloading due to rapid sea-level drawdown can trigger magmatic pulses.

Main Methods:

• Calculating surface load variations associated with the Messinian salinity crisis.
• Compiling temporal data for Mediterranean magmatism.
• Employing numerical modeling for mantle decompression melting and dike formation.

Main Results:

• Scenarios with kilometer-scale sea-level drawdown correlate with significant lithospheric unloading.
• This unloading phase appears synchronous with a pulse of magmatism across Mediterranean igneous provinces.
• Numerical models confirm a mechanistic link between unloading and magma generation.

Conclusions:

• The Mediterranean magmatic record independently validates the controversial kilometer-scale evaporative drawdown theory.
• This research highlights the sensitivity of magmatic systems to surface load variations, offering new insights into geological processes.