Enrichment of Platinum Group Elements in Lower Cambrian Polymetallic Black Shale, SE Yangtze Block, China

Platinum group elements (PGEs) occur mainly in basic–ultrabasic igneous rocks and are concentrated by the differentiation crystallization of magma. Thin polymetallic layers including Ni, Mo, V, PGEs, rare-earth widely developed lower Cambrian black shales southern China. The PGE contents such may not be economically significant but still unusually enriched. enrichment mechanisms have been studied, here compositions Shuidong (Nayong) Niuchang (Weng’an) sections SE Yangtze block China were determined, results compared with published data for region. Results indicate that PGEs enriched layers, whereas surrounding country barren. ΣPGE Ni–Mo deposits generally than V deposits. distribution patterns similar to those rocks, indicating played a role enrichment. Oceanic hypoxia during Sinian–Cambrian transition resulted production large amounts organic matter H 2 S ocean. When high-salinity brine reached ocean bottom, rapid changes Eh–pH conditions caused metals at sediment–seawater interface, this was later enhanced diagenesis.