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DOI	10.1130/B36530.1
	Origin of Late Cretaceous, enclave-bearing granitoids in southern Tibet: Implications for magma recharge and crustal thickening
	Wen, Ding-Jun; Hu, Xiumian; Yu, Jin-Hai; Wang, Xiao-Lei; Chapman, Timothy; Wang, Rui-Qiang
发表日期	2023
ISSN	0016-7606
EISSN	1943-2674
起始页码	2391
结束页码	2406
卷号	135 期号:9-10
英文摘要	Exposures of enclave-bearing granitoids can provide rare opportunities to directly evaluate the connection between compositional variability and the depth of origin of arc magmatic rocks. The similar to 1000 km long Gangdese batholith is a composite batholith with composition from mafic to felsic; SiO2 ranges from 51 wt% to 70 wt%. New zircon U-Pb dating of the Nyemo plutons, Renbu plutons, and Xigaze plutons in the Gangdese batholith is consistent with their emplacement and crystallization in the Late Cretaceous (ca. 90-85 Ma). Mafic magmatic enclaves (MMEs) in the plutons are characterized by low SiO2 (50.9-56.0 wt%) and Nb/U, Ce/Pb, and Nb/La ratios coupled with enrichment in light rare earth elements and large ion lithophile elements and depletion in high field strength elements. These geochemical features, combined with depleted whole-rock eNd(t) (+4.2 to +4.7) and zircon epsilon(Hf)(t) (+9.0 to +13.8), suggest that they were derived by partial melting of a depleted mantle source associated with subductionrelated fluids. The granitoids with high SiO2 (55.6-66.9 wt%) display adakitic geochemical characteristics, such as low Y and Yb contents, and high Sr/Y and La/Yb ratios. Their positive whole-rock epsilon(Nd)(t) (+4.0 to +5.5) and zircon epsilon(Hf)(t) (+6.9 to +14.3) values, as well as enrichment of incompatible elements, indicate that the granitoids were derived from partial melting of the juvenile lower crust. Geochemical modeling suggests that the compositional diversities of MMEs and adakitic granitoids were inherited from heterogeneous sources. This genetic relationship
英文关键词	SLAB ROLL-BACK; LHASA TERRANE; CONTINENTAL-CRUST; ADAKITIC AFFINITIES; GANGDESE BATHOLITH; MANTLE WEDGE; HYBRID MAGMA; ARC MAGMAS; MILIN AREA; LU-HF
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:001101571800012
来源期刊	GEOLOGICAL SOCIETY OF AMERICA BULLETIN
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283476
作者单位	Nanjing University; University of New England; China University of Geosciences - Beijing
推荐引用方式 GB/T 7714	Wen, Ding-Jun,Hu, Xiumian,Yu, Jin-Hai,et al. Origin of Late Cretaceous, enclave-bearing granitoids in southern Tibet: Implications for magma recharge and crustal thickening[J],2023,135(9-10).
APA	Wen, Ding-Jun,Hu, Xiumian,Yu, Jin-Hai,Wang, Xiao-Lei,Chapman, Timothy,&Wang, Rui-Qiang.(2023).Origin of Late Cretaceous, enclave-bearing granitoids in southern Tibet: Implications for magma recharge and crustal thickening.GEOLOGICAL SOCIETY OF AMERICA BULLETIN,135(9-10).
MLA	Wen, Ding-Jun,et al."Origin of Late Cretaceous, enclave-bearing granitoids in southern Tibet: Implications for magma recharge and crustal thickening".GEOLOGICAL SOCIETY OF AMERICA BULLETIN 135.9-10(2023).