Knowledge Management System Of Guangzhou Institute of Geochemistry，CAS
| Ma, Jian-Feng1,2,3; Zhao, Tai-Ping1,2; Hou, Tong4; Qu, Chuan-Hao1,2,3 | |
| Mineral Textures and Chemistry Trace the Origin and Transcrustal Evolution of the Sanyuangou Syenite in Southern North China Craton | |
| Source Publication | JOURNAL OF PETROLOGY
 |
| ISSN | 0022-3530 |
| 2024-06-06 | |
| Volume | 65Issue:6Pages:24 |
| DOI | 10.1093/petrology/egae056 |
| Language | 英语 |
| WOS Research Area | Geochemistry & Geophysics |
| Abstract | Alkaline rocks are widely distributed in various geological environments and are important carriers for exploring the formation and compositional diversity of continental crust. Extensive studies have investigated the processes of mantle melting and crustal differentiation that produced such rocks. However, the potential interaction processes between mantle-derived magma and crust during their formation are poorly constrained. In this study, we focus on a Paleoproterozoic garnet-bearing syenite in the Xiong'er large igneous province (LIP) on the southern margin of the North China Craton through detailed whole-rock and mineral analyses. The high K2O (7.4-8.8 wt %) syenite emplaced at similar to 1772 Ma with ancient inherited zircon (1800-2800 Ma). The dominant mineral assemblage is composed of clinopyroxene, garnet, and K-feldspar with a small amount of titanite. Complex compositional oscillatory zoning of clinopyroxene and garnet indicates that magma mixing played a significant role in the formation of the syenite. We estimated the major elements composition for melts in equilibrium with clinopyroxene and calculated the clinopyroxene/melt partition coefficients by crystal lattice strain model, thus calculating the trace elements of the equilibrated melts. The equilibrium melts of high Mg-# (>85) clinopyroxene have high CaO/Al2O3 (>0.6) and low H-f/S-m (<0.4), which suggests a role for carbonatitic metasomatism of the mantle. The variables La/Yb (24.4-56.1), Dy/Yb (0.8-5.9), and Yb (0.6-10.3 mu g/g) indicate that the initial melts were formed by 1% to 2% partial melting of spinel-garnet phlogopite lherzolite. An REE-based model for melts in equilibrium with low Mg-# (<85) clinopyroxene indicates that 10% to 30% felsic magma from ancient crust participated in hybridization. In addition to well-documented magma mixing, the oscillatory zoning of garnet is also related to competition with titanite. The initial alkaline magmas have a high water content (similar to 4 wt %), which delays the crystallization of K-feldspar, leading to the enrichment of K2O, until the K-feldspar accumulates in the shallow crust to form the syenite. Magma mixing under an open system further leads to alkalinity enrichment. Magma source and crustal evolution jointly determine the potassium-rich characteristics of syenite. Multiple episodes of magma mixing and fractional crystallization occur in the crust (700-300 MPa), suggesting complex and vertically extensive magma chambers. This study represents the first identification of carbonatitic metasomatism as a mantle source in the Xiong'er LIP. Furthermore, it offers a new perspective on magma mixing between the mantle and crust in transcrustal magmatic systems, contributing to the formation of alkaline rocks. |
| Keyword | syenite magma mixing carbonatic metasomatism magmatic water Xiong'er large igneous province |
| WOS ID | WOS:001249229300001 |
| Indexed By | SCI |
| Citation statistics | |
| Document Type | 期刊论文 |
| Identifier | http://ir.gig.ac.cn/handle/344008/78403 |
| Collection | 同位素地球化学国家重点实验室 |
| Corresponding Author | Zhao, Tai-Ping |
| Affiliation | 1.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Kehua St 511, Guangzhou 510640, Peoples R China 2.Chinese Acad Sci, Ctr Excellence Deep Earth Sci, Kehua St 511, Guangzhou 510640, Peoples R China 3.Univ Chinese Acad Sci, Yuquan St 19, Beijing 100049, Peoples R China 4.China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Xueyuan Rd 29, Beijing 100083, Peoples R China |
| Recommended Citation GB/T 7714 | Ma, Jian-Feng,Zhao, Tai-Ping,Hou, Tong,et al. Mineral Textures and Chemistry Trace the Origin and Transcrustal Evolution of the Sanyuangou Syenite in Southern North China Craton[J]. JOURNAL OF PETROLOGY,2024,65(6):24. |
| APA | Ma, Jian-Feng,Zhao, Tai-Ping,Hou, Tong,&Qu, Chuan-Hao.(2024).Mineral Textures and Chemistry Trace the Origin and Transcrustal Evolution of the Sanyuangou Syenite in Southern North China Craton.JOURNAL OF PETROLOGY,65(6),24. |
| MLA | Ma, Jian-Feng,et al."Mineral Textures and Chemistry Trace the Origin and Transcrustal Evolution of the Sanyuangou Syenite in Southern North China Craton".JOURNAL OF PETROLOGY 65.6(2024):24. |
| Files in This Item: | There are no files associated with this item. | |||||
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.
Edit Comment