17:15 〜 18:45
[MIS23-P03] パンダヒル産ソバイト様カーボナタイトに含まれる初生流体包有物
キーワード：カーボナタイト、流体包有物、初生包有物、パンダヒル
Carbonatites, defined by either >30 vol% of igneous carbonate minerals or >50 wt% of carbonate in igneous rocks, host the largest deposits of rare earth elements (REEs) and niobium (Nb), making them critical sources of 'essential elements.'
In the East African rift system of western Tanzania, the Panda Hill Carbonatite Complex of Cretaceous age is notable for its pyrochlore-bearing sovite-type carbonatite (e.g., Boniface, 2017). This study investigates the primary magmatic fluids by examining fluid inclusions within calcite and apatite from the sovite carbonatite at Panda Hill Complex. The analyzed sovite samples contain mainly calcite with a subordinate amount of apatite, and minor accessory minerals such as magnetite, phlogopite, and pyrochlore.
Our observations reveal that both calcite and apatite host abundant fluid inclusions. In calcite, these are predominantly pseudosecondary and secondary (1 to 10 μm in size), and exhibit varied morphologies including spherical, polygonal, and irregular shapes. In contrast, primary fluid inclusions with spherical shapes (1 to 15 μm in size), dominate in apatite. Fluid inclusions in both minerals vary from liquid-only, two-phase (liquid with gas), to multiphase (liquid with gas and daughter mineral phases), regard less of their generation.
This poster presentation will detail our preliminary results on the characteristics of primary fluid inclusions, supplemented by Raman spectroscopic analysis.
In the East African rift system of western Tanzania, the Panda Hill Carbonatite Complex of Cretaceous age is notable for its pyrochlore-bearing sovite-type carbonatite (e.g., Boniface, 2017). This study investigates the primary magmatic fluids by examining fluid inclusions within calcite and apatite from the sovite carbonatite at Panda Hill Complex. The analyzed sovite samples contain mainly calcite with a subordinate amount of apatite, and minor accessory minerals such as magnetite, phlogopite, and pyrochlore.
Our observations reveal that both calcite and apatite host abundant fluid inclusions. In calcite, these are predominantly pseudosecondary and secondary (1 to 10 μm in size), and exhibit varied morphologies including spherical, polygonal, and irregular shapes. In contrast, primary fluid inclusions with spherical shapes (1 to 15 μm in size), dominate in apatite. Fluid inclusions in both minerals vary from liquid-only, two-phase (liquid with gas), to multiphase (liquid with gas and daughter mineral phases), regard less of their generation.
This poster presentation will detail our preliminary results on the characteristics of primary fluid inclusions, supplemented by Raman spectroscopic analysis.