Sulfide saturation in alkaline to peralkaline igneous rocks.
Final Report Abstract
Samples from several alkaline to peralkaline plutonic and sub-volcanic rocks where investigated for their sulfide inventory, their compositional variation and their S isotopic composition. The results of these studies revealed that (i) besides Fesulfides, chalcopyrite, sphalerite and galena are the most important sulfide minerals. In such rock types. (ii) Systematic compositional differences between sulfides in primitive and evolved rocks of a given locality can be interpreted in terms of magma differentiation (iii) Sulfur isotope variations in these samples are largely governed by the prevailing redox conditions during magma differentiation, cooling, and degassing/ fluid exsolution. Importantly, a global δ34S compilation for alkaline rocks and carbonatite reveals secular variation in alkaline magma sources, indicting changes in the sulfur isotopic composition of the lithospheric mantle and/or Ga timescales for deep crustal recycling.
Publications
- (2018): Sulfides in alkaline and peralkaline rocks: textural appearance and compositional variations. Neues Jahrbuch Mineralogie Abhandlungen 195, 155-175
Babiel, R., Marks, M.A.W., Neumann, U., Markl, G.
(See online at https://doi.org/10.1127/njma/2018/0095) - (2019): Sulphur isotopes of alkaline magmas unlock long-term records of crustal recycling on Earth. Nature Communications 10, 4208
Hutchinson, W., Babiel, R.J., Finch, A.A., Marks, M.A.W., Markl, G., Boyce, A.J., Stüeken, E.E., Friis, H., Borst, A.M. & Horsburgh, N.J.
(See online at https://doi.org/10.1038/s41467-019-12218-1)
