Health & Environmental Research Online (HERO)


Print Feedback Export to File
7461971 
Journal Article 
[The petrogenesis of the Early Cretaceous Sanguliu pluton in the Liaodong Peninsula, NE China: Constrained from the trace element modelling and Sr-Nd isotopes] 
Wang, ZQ; Huhua, ZF; Chen, B; Duan, XX; Zhou, TF; Jiang, X 
2020 
1 
Yanshi Xuebao / Acta Petrologica Sinica
ISSN: 1000-0569 
36 
12 
3683-3704 
Chinese 
WOS:000605101000008 
Large-scale magmatic activity and gold mineralization occurred in the Liaodong Peninsula during the Mesozoic, especially in the Cretaceous Era. In this paper, we report LA-ICPMS U-Pb ages, whole-rock geochemistry and Sr-Nd isotopic data for the Early Cretaceous Sanguliu pluton. The Sanguliu pluton is composed of porphyritic coarse-grained amphibole biotite granite, the fine-grained biotite granite and the late diorite dyke that cut through the amphibole biotite granite. They emplaced at 125. 1 +/- 1. 2Ma, 128. 7 +/- 2. 2Ma and 125. 1 +/- 2. 4Ma, respectively. The amphibole biotite granite is metaluminous high-K2O calc-alkaline I-type granite with high H2O content and high f(02). The trace-element modelling and Sr-Nd isotopes indicate that the amphibole biotite granite was derived from the partial melting of the Paleo-Proterozoic meta-mafic rocks and the meta-andesite of the Liaohe Group. The fine-grained biotite granite was derived from the amphibole biotite granite through intensive fractional crystallization with separate phases of potassium feldspar, plagioclase, amphibole, biotite and quartz. Depletion in MREE of fine-grained biotite granite indicates titanite as an important additional separate phase. The diorite dyke have high Mg-# (0. 51 similar to 0. 52) and high Sr/Y ratios (83. 3 similar to 85. 5), and belongs to high-Mg adakitic diorite. They have low initial Sr-87/Sr-86 ratio (0. 708723) and negative epsilon(Nd)(t) values (- 14. 1), which indicate that the diorite dyke derived from a process of magma mixing between siliceous crustal melts and basaltic magma from enriched lithospheric mantle. In the Early Cretaceous, the Liaodong Peninsula was in an extensional environment related to the subduction of the Paleo-Pacific Plate. The underplated hot basalt derived from the enriched lithospheric mantle deduced the partial melting of the lower crust and the intensive fraction crystallization, which formed the Sanguliu pluton. Simultaneously, the basaltic magma mixed with a certain portion of the granitic melt during the ascending process, forming the adakitic high Mg diorite dyke. 
Liaodong Peninsula; Sanguliu; rock mass; trace element modelling; separation of crystalline; high-magnesium diorite