|
|||||
|
|
Sr–barite droplets associated with sulfide blebs in clinopyroxene megacrysts from basaltic tuff (Szentbékkálla, western Hungary) |
|
| Authors: | Klmn Trk Enik Bali Csaba Szab Jnos Antal Szakl |
| Institution: | a Research Group for Geophysics and Environmental Physics of the Hungarian Academy of Sciences, Department of Geophysics, Eötvös University, Pázmány Peter sétány 1/C, H-1117, Budapest, Hungary b Lithosphere Fluid Research Laboratory, Department of Petrology and Geochemistry, Eötvös University, Pázmány Peter sétány 1/C, H-1117, Budapest, Hungary |
| Abstract: | A unique occurrence of strontian barite droplets associated with oriented planes of primary sulfide blebs in several clinopyroxene megacrysts was found in the Plio-Pleistocene basaltic tuff of Szentbékkálla (Bakony–Balaton Highland, western Hungary). The barite droplets contain 3.22–14.7 wt.% SrO, variable amount of FeO (up to 3.25 wt.%), minor CaO, CuO and NiO. Textural arrangements of oriented sulfide planes show that they were trapped as immiscible sulfide melt during crystallization of the clinopyroxene. Temperature and pressure estimation (978–1094 °C and 1.0–1.1 GPa) of the host clinopyroxenes indicate that formation of clinopyroxene megacrysts and entrapment of sulfide blebs happened under upper mantle conditions. A genetic relationship between the sulfate and sulfide blebs is doubtful. Textural features suggest that the barite droplets might have been trapped together with the sulfide blebs from immiscible sulfide melts. However, it cannot be excluded that the barite formed during metasomatic event following the sulfide formation. |
| Keywords: | Bakony–Balaton Highland Sulfide and sulfate inclusions Clinopyroxene megacrysts Immiscibility Metasomatism |
| 本文献已被 ScienceDirect 等数据库收录！ | |