Research Field: Genesis of Granite and Related Rocks
The Earth distinguishes from other planets by the existence of massive granitoids and continental crust, while granitoids occupy a significant position in the spectrum of continent. Thus, investigating the petrogenesis of granite and the formation of granitic plutons/batholiths plays a crucial role in understanding the formation and evolution of continents, and it is what we have been devoted to.
(1) The A-type granites in the Mesozoic granitic belt have more depleted Nd-Hf isotopic composition than that of contemporaneous I- and S- type granites. The distribution of the A-type granites may be along the Neoproterozoic amalgamation belt of the Yangtze and Cathaysia Block, where have more juvenile material than the source of the I- and S-type granites. Thus, the generation of Mesozoic granites in Nanling area more likely support the source controlled model.
(2) Southern China experienced extensive, episodic, Mesozoic granitic magmatism and W–Sn polymetallic mineralization, making this area an ideal natural laboratory for the study of granitic magmatism and related metallogenesis. We proposed a deep crustal hot zone (DCHZ) to account for these granitoids within the Jiuling composite batholith, which has not previously been recognized beneath the South China Block.
(3) The coupling and decoupling relationship between mantle- and crust-derived magmatism at different stages of subduction-suture zone is explored through the petrogenesis research on Neoproterozoic high-Mg tonalite and the discussion on the magma source melting progress of mafic-ultramafic rocks from northern Guangxi.
(4) The magmatic evolution of Permian mafic-felsic volcanic rocks from Tu Le Basin of northern Vietnam is studied to explore the episodic evolution and eruption of volcanic rocks under the extension background related to mantle plume as well as the coupling relationship between mantle- and crust-derived magmatism.
(5) By combining mineral assemblage, field relationship, and thermodynamic modeling data with observations of zircon internal structures, we infer that anatexis occurred via partial melting of Neoproterozoic metasedimentary rocks, immediately following amphibolite-facies regional metamorphism at ca. 442 Ma for the granitic rocks in the northern Wuyi Mountains of southern Jiangxi Province. Three types of zircon grains/domains in the analyzed samples were identified, relating to anatectic melt migration, extraction, and eventual crystallization. Large variations in zircon Hf isotopic compositions and homogenization trends indicate that melting was heterogeneous, and homogenization of the anatectic melt occurred later.
(6) Based on the field work, petrography, geochemistry and numerical simulation, we regard the Oligocene (ca. 30 Ma) Gangdese leucogranite in southern Tibet as the latest product of fractional crystallization from coeval host granitoids which derived from the anatexis of juvenile lower crust. This work also stresses the crucial role of water-present melting and delamination in the formation of continental crust. The first report of Oligocene Gangdese leucogranites, along with compilations of synchronous high Sr/Y Gangdese granitoids and Himalayan leucogranites, indicate the existence of diverse sources, generations and evolutions of granitic magmatism in southern Tibet may be resulted from partial melting of local deep crustal materials.
(7) U-Pd-Hf data imply the existence of a Paleoproterozoic basement and suggest that the late Mesozoic continental arc magmatism in the Eastern Cathaysia Blok was most likely developed on and contaminated by the basement.
(8) Numerical simulations show great potential for intrusive magmas to generate large amounts of CO2. Geological big data implies a close relationship between magmatism and climate change.