Deglaciation and glacial erosion: A joint control on magma productivity by continental unloading

Pietro Sternai (1, 2) , Luca Caricchi (2) , Sébastien Castelltort (3) , Jean-Daniel Champagnac (4)

1 Division of Geological and Planetary Sciences [Pasadena]
2 Department of Earth Sciences [University of Cambridge]
3 UNIGE - Université de Genève = University of Geneva
4 Geological Institute [ETH Zürich]

Glacial-interglacial cycles affect the processes through which water and rocks are redistributed across the Earth's surface, thereby linking the solid Earth and climate dynamics. Regional and global scale studies suggest that continental lithospheric unloading due to ice melting during the transition to interglacials leads to increased continental magmatic, volcanic, and degassing activity. Such a climatic forcing on the melting of the Earth's interior, however, has always been evaluated regardless of continental unloading by glacial erosion, albeit the density of rock exceeds that of ice by approximately 3 times. Here we present and discuss numerical results involving synthetic but realistic topographies, ice caps, and glacial erosion rates suggesting that erosion may be as important as deglaciation in affecting continental unloading. Our study represents an additional step toward a more general understanding of the links between a changing climate, glacial processes, and the melting of the solid Earth.

Domains: Geophysics [physics.geo-ph]; Glaciology

Pietro Sternai, Luca Caricchi, Sébastien Castelltort, Jean-Daniel Champagnac. Deglaciation and glacial erosion: A joint control on magma productivity by continental unloading. Geophysical Research Letters, 2016, 43 (4), pp.1632-1641. ⟨10.1002/2015GL067285⟩. ⟨insu-01396414⟩