Lüliang Group in Central Lüliang Mountain, Shanxi was deposited in Early Proterozoic(∼ 2. 1Ga). Its upper part comprises meta-basalt and meta-rhyolite (bimodal volcanism). The rhyolites are characterized by high LIL and HFS elements and large Rb/Sr and Ga/Al ratios, similar with A-type granitoid rocks. The basalts have low TiO2 and P2O5 content and are enriched in LIL and LREE. Geochemical studies indicate that the volcanic rocks of Lüliang Group were erupted in rift-type tectonic setting on continental margin. The parental magma of the basalts was derived from lower depleted mantle source and underwent fractional crystallization and contamination. The rhyolites originated from the partial melting of lower crustal granulites. triggered by high heat fluid and basaltic magma emplacement in the rift environment.
|Journal||Acta Petrologica Sinica|
|Publication status||Published - 1997|
- Bimodal volcanism
- Early proterozoic
- Lüliang group
- Shanxi province