2007/01/18 by Katrin Mierdel, Hans Keppler, Joseph R. Smyth +1 · 5 citations
Earth and Planetary Sciences · Chemistry · #High-pressure geophysics and materials #Geological and Geochemical Analysis #earthquake and tectonic studies #Asthenosphere #Solubility #Geology #Lithosphere #Silicate #Mantle (geology) #Geochemistry #Olivine #Petrology #Geophysics #Tectonics #Chemistry
paper · doi:10.1126/science.1135422
openalex publication_date 2007/01/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/23
Plate tectonics is based on the concept of rigid lithosphere plates sliding on a mechanically weak asthenosphere. Many models assume that the weakness of the asthenosphere is related to the presence of small amounts of hydrous melts. However, the mechanism that may cause melting in the asthenosphere is not well understood. We show that the asthenosphere coincides with a zone where the water solubility in mantle minerals has a pronounced minimum. The minimum is due to a sharp decrease of water solubility in aluminous orthopyroxene with depth, whereas the water solubility in olivine continuously increases with pressure. Melting in the asthenosphere may therefore be related not to volatile enrichment but to a minimum in water solubility, which causes excess water to form a hydrous silicate melt.