View article

The Yanhu area in the northern Lhasa subterrane exposes diverse rock types including basalts, rhyolites, quartz dioritic porphyries, and associated dioritic enclaves. The basalts and rhyolites occur as a bimodal volcanic suite, and the quartz dioritic porphyries intrude into the older basalts as a small apophysis. In this paper, we report for the first time the zircon LA-ICP-MS U–Pb age and Hf isotopic composition data, whole-rock major and trace element composition data, and Sr–Nd isotopic data from the diverse Early Cretaceous magmatic rocks from Yanhu. The three basalt samples that we dated yielded zircon U–Pb ages of 110±0.7Ma, 108.9±1.1Ma, and 111.8±3.2Ma. The zircons from one quartz diorite porphyry yielded an age of 109.7±0.8Ma, which is coeval with the dioritic enclave (110.4±1.4Ma). The basalts show a high-K calc-alkaline signature, enriched in Rb, Th, U, and light rare earth elements (REEs) and …