Light rare earth element systematics as a tool for investigating the petrogenesis of phoscorite-carbonatite associations, as exemplified by the Phalaborwa Complex, South Africa

Three-dimensional textural investigation of sulfide mineralisation from the Loolekop carbonatite–phoscorite polyphase intrusion in the Phalaborwa Igneous Complex (South Africa), with implications for ore-forming processes

“…These ages suggest a synchronous emplacement of the main geological units. Compositions of banded carbonatite and phoscorite indicate a cogenetic origin of these two rocks, which support the concept of a rapid emplacement of the Loolekop carbonatite–phoscorite complex (Wu et al , 2011; Milani et al , 2017a, b).…”

“…This feature furthermore suggests a cogenetic origin for the two rock types and control of immiscibility between their parent melts, similar to other occurrences of carbonatite–phoscorite intrusions (Brod et al , 2013). Textural and compositional uniformity of fluorapatite and calcite supports a cogenetic emplacement of both carbonatite and phoscorite in the Loolekop Pipe (Milani et al , 2017b). On the basis of the composition of apatite and mica, Giebel et al (2019) also advocated a common origin for these two rocks.…”

“…In the Loolekop Pipe, immiscibility combined with density difference and magmatic flow leads to the preferential emplacement of phoscorite along the edges of the intrusion (Basson et al , 2017; Giebel et al , 2019). Another possibility for the genesis of the carbonatite and phoscorite involves fractional crystallisation (Skulski et al , 1994; Veksler et al , 1998; Chakhmouradian, 2006; Milani et al , 2017a, b). Mineralogical zoning was also observed in both the Kovdor and Salmagorskii intrusions and ascribed to fractional crystallisation (Korobeinikov et al , 1998; Ivanyuk et al , 2016).…”

Composition and U—Pb ages of apatite in the Amba Dongar carbonatite–alkaline complex, India

“…The analytical standards comprised mineral mounts of apatite (Ca, P, Si, F, and Cl), pyrite (S), celestite (Sr), rhodonite (Mn), magnetite (Fe), albite (Na), and REE phosphates. The operating conditions (15 μm beam diameter, 20 nA beam current, and 15 kV accelerating voltage) and analytical protocol follow that of Milani, Bolhar, Frei, Harlov, and Samuel (). The detection limits typically range from 200 to 300 ppm for all analysed elements.…”

“…The respective geographic coordinates of the sample locations have been provided in Table S1. Apatite in AC1 is rare but elongate grains measuring up to 2 mm long are present in Milani, Bolhar, Frei, Harlov, and Samuel (2017). The detection limits typically range from 200 to 300 ppm for all analysed elements.…”