New insights from zircon and apatite saturation thermometry in selected Permo-Carboniferous igneous rocks of Central Europe

The Late Palaeozoic continental rift system in Central Europe was the cause of pronounced magmatic activity, which led to the intrusion of numerous plutonic and subvolcanic bodies and voluminous pyroclastic deposits in numerous calderas. In particular, the petrogenetic evolution of magmatic systems provides an interesting field of research due to the heterogeneous composition of the basement. Hence, geothermometers are an important analytical tool for understanding such petrogenetic evolution and are used to determine the formation temperature of the post-orogenic igneous suite between the Altmark (Saxony-Anhalt) and the granulite massif (Saxony).

Calculated saturation temperatures of zircon and apatite from igneous rocks of the Central European Extension Province of the present study show two significant trends. The comparison of the saturation temperature values of zircon (T_Zrn) and apatite (T_Ap) from rocks of well-known Cenozoic deposits of the Basin and Range Province in the southwestern United States with that of the Central European Extension Province suggests that large differences between the saturation-temperature values (T_Ap >> T_Zrn) indicate a zoned magma chamber, while saturation-temperature values close to each other (T_Ap ≥ T_Zrn) indicate magma mixing.