Abstract
Phosphorus behaves as an incompatible element during the early stages of crystallization of basaltic magmas, and due to its high solubility in depolymerized melt (Harrison and Watson, 1984) enrichments of up to 2 -3 wt% P205 have been documented for a number of natural basic magmas before saturation of phosphate phases (Anderson and Greenland, 1969). Both of the features suggest that phosphorus can give valuable constraints on models of magma crystallization, such as the extent of crystallization along a liquid line of descent or the relative amount of trapped liquid in basic cumulate rocks (Henderson, 1968). In order to facilitate a quantitative interpretation of cristallisation processes of basalt, we present in this paper new crystal]liquid distribution coefficients for phosphorus. Since basaltic magmas enriched in phosphorus are also enriched in iron, a ferrobasaltic composition (Mg# = 0.37) was used as starting material in this experimental study. Phosphorus content of coexisting crystals and liquid was then analyzed with ion probe.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have