Abstract:
In order to explore the magmatic origin and tectonic setting of the Jiuling pluton in northern Jiangxi, a combined study of geochronology, geochemistry and zircon Lu-Hf isotope was carried out for the Dahutang biotite granodiorite. LA-ICP-MS zircon U-Pb dating of biotite granodiorite suggests it was formed at (835.6±1.5) Ma. Geochemistry analysis shows it belongs to the series of potassium-high potassium calcium alkaline peraluminous granite. It has the typical characteristics of S-type granite and it was derived from the melting of the Neoproterozoic Shuangqiaoshan Group. The positive zircon
εHf (
t) value (2.8-8.2) suggests that the magma forming the granite was originated from the recycling of Proterozoic crustal material. The Dahutang biotite granodiorite was formed in a tectonic background of transition stage from syn-collision to post-collision. Combining with previous studies, it is inferred that that the upper time limit of collision between the Yangtze and Cathaysia plate should be about 835 Ma.