Permian arc–back-arc basin development along the Ailaoshan tectonic zone: Geochemical, isotopic and geochronological evidence from the Mojiang volcanic rocks, Southwest China

This paper presents a set of new SHRIMP zircon U–Pb geochronological, elemental and Sr–Nd–Pb isotopic data for the Wusu and Yaxuanqiao basaltic rocks (the Mojiang area) along the Ailaoshan tectonic zone. The Wusu basaltic sequence is dominated by SiO2-poor, MgO- and TiO2-rich basalts with a major mineral assemblage of plagioclase + clinopyroxene. These rocks gave a SHRIMP zircon U–Pb age of 287 ± 5 Ma (MSWD = 0.58). In contrast, the Yaxuanqiao...