Summary
Abyssal tholeiite is generated by partial melting of the upper mantle. The mantle sections of ophiolite complexes show that partial melting leaves mantle residua that are lherzolitic or harzburgitic, harzburgite being the more depleted residuum. It is shown that some of the interstitial melt of partially molten harzburgite approximates a tholeiitic composition. Therefore, the solidus of harzburgite constitutes the maximum possible temperature for the generation of primary tholeiite. The MgO contents of primary tholeiites in equilibrium with harzburgite are determined to be about 21 and 23 wt.% MgO at 2.0 and 3.0 GPa, respectively. The possible MgO contents of primary abyssal tholeiite is suggested to range between 10 and 23 wt.% MgO, with the MgO content increasing with increasing pressure.
Similar content being viewed by others
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Maaløe, S. The solidus of harzburgite to 3 GPa pressure: the compositions of primary abyssal tholeiite. Mineralogy and Petrology 81, 1–17 (2004). https://doi.org/10.1007/s00710-004-0028-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00710-004-0028-6