Carbonatites in China: A review

Zircon from the East Orebody of the Bayan Obo Fe–Nb–REE deposit, China, and SHRIMP ages for carbonatite-related magmatism and REE mineralization events

“…The succession is best shown in Tao et al, (1998), Fan et al (2006), and in Yang et al (2011a) along with the locations of some carbonatite dykes in the region. Yang and Woolley (2006) affirm the recent recognition of H9 (previously described as slate), as metamorphosed trachyte and basalt, with reference to the work of Hao et al (2002). Other authors have also reported alkaline igneous rocks in the region of a variety of ages since about ~1.9 ga (e.g.…”

“…Drew et al 1990;Campbell and Henderson 1997;Yang et al 2003;Mitchell 2005;Yang and Woolley 2006;le Bas et al 2007;Kynicky et al 2012;Smith et al 2014) and that the world-class ree-ore mineral deposits there mainly originate from carbonatite-derived fluids (e.g. Fan et al 2006;Smith 2007), a comparison of zircons in the present study with those of known carbonatitic association (Mud Tank and Kovdor) is essential.…”

“…Small carbonatite dykes (1-2 m thick) intrude various parts of the Bayan Obo group within a few km of the orebodies (Drew et al 1990;Tao et al 1998;le Bas et al 1992;Yang et al 2003;Yang and Woolley 2006;le Bas et al 2007) and are dated at 1,354 ± 59 (Yang et al 2011a). Zircons in three carbonatite dykes in the Bayan Obo region yield dates of 1,894-1,956 Ma and unremarkable Th/U ratios, and they contain inclusions of quartz and feldspar, features which are consistent with basement inheritance as reported by liu et al (2008) (see Table 1).…”

Formation of the world's largest REE deposit through protracted fluxing of carbonatite by subduction-derived fluids

“…In addition to the ore bodies, there are two main types of carbonatite dykes in the Bayan Obo ore district, dolomitic and calcitic, distinguished on the basis of the dominant carbonate mineral89. Proposed models for the richness and genesis of the ore include carbonatite magmatism51011121314151617, alteration/metasomatism of sedimentary carbonate rocks by hydrothermal fluids2141819202122232425, deposition of carbonates on the sea floor accompanied by simultaneous metasomatism626, epigenetic processes related to Palaeozoic plate subduction27, and a polyphase model involving multiple periods of alkaline magmatism, metamorphism and deformation and potentially subsequent infiltration of Caledonian-age fluids derived from subduction-related granitoids282930. The debate centres on the genetic relationship between the REE and Fe ore bodies and associated carbonatite dykes and sedimentary dolomite.…”

A deposit model for carbonatite and peralkaline intrusion-related rare earth element deposits

“…About 40 percent of the world's known occurrences of carbonatite are in Africa (Woolley, 2001). China, currently the world's leading supplier of REE (as of 2012), has 27 known occurrences of carbonatite (Yang and Woolley, 2006). Brief descriptions of alkaline provinces and individual alkaline complexes are available for North and South America (Woolley, 1987), the former U.S.S.R. (Kogarko and others, 1995), and Africa (Woolley, 2001); these volumes are useful sources of information for the initial stages of REE exploration.…”