| Main results | Theoretical results: - Acquired the high quality and precise database on mineral assemblages, chemical compositions of minerals, chemical compositions of major, trace, and rare elements, Sr, Nd, and Hf isotopes, and age dating (U-Pb zircon, LA-ICP-MS and CA-ID-TIMS )of northwest Vietnam’s granitoids. This dababase is the necessary for furthering study on petrology Permian-Triassic granitoids in Vietnam and adjacent areas; - Based on the mineralogical, geochemical and isotopic data, the NWVN granitoids is categorized into I-type granitoids (Nam Meng, Nam Rom, and Song Ma massifs) and S-type granitoids (Pu Si Lung, Kim Boi, Muong Lat, and Sam Son massifs). This result has been combined into a manuscript and going to be sent to publish on Vietnam Journal of Earth Sciences; - Propose the two stages magma mixing model forming Permian-Triassic I- and S-type granitoids in NWVN: Stage I: Formation of early I-type granitoid from mixed magma between mafic (gabbro) and felsic magmas; Stage II: Formation of granitoids from mixed magma between stage I felsic magma and less radioactive felsic magma, that melted from Paleoproterozoic basement and sedimentary rocks; - New data on the age dating of the Nam Rom and Song Ma massifs (242-229 Ma) suggests that they were post-collision magmatic activities in the North segment of the Truong Son Fold Belt; - New and precisely age datings of Phan Si Phan-Tu Le alkaline granitoids and rhyolites (257-256 Ma) eluciate the timing of alkalic felsic magma activity, which is related with mantle plume in NWVN. It is usefull to reconstruct paleo-geography of the Phan Si Phan and Tu Le zones during Permian-Triassic period, interprete the paleo-climate and the Permian mass extinction in South East Asia. This results were published on Geology and Lithos. Educational results: Improve the research capacity on petrology and metallogeny of the researchers of the Institute of Geological Sciences, VAST: - 01 Doctor student graduated from National Taiwan Normal University (NTNU); - 01 young researcher was trained in NTNU. |
| Products of the project | Scientific papers in referred journals - SCI papers: Pham, T. T., Shellnutt, J. G., Tran, T. A., and Lee, H.-Y., 2020, Petrogenesis of Eocene to early Oligocene granitic rocks in Phan Si Pan uplift area, northwestern Vietnam: Geochemical implications for the Cenozoic crustal evolution of the South China Block: Lithos, v. 372-373, p. 105640. Shellnutt, J. G., Pham, T. T., Denyszyn, S. W., Yeh, M.-W., and Tran, T. A., 2020, Magmatic duration of the Emeishan large igneous province: Insight from northern Vietnam: Geology, v. 48, no. 5, p. 457-461. Thuy Thanh Pham, F. Gregory Shellnutt, Tuan-Anh Tran, Steven W. Denyszyn, and Yoshiyuki Iizuka, 2021, Petrogenesis of Silicic Rocks from the Phan Si Pan- Tu Le region of the Emeishan Large Igneous Province, Northwestern Vietnam: Geology Society, London, Special Publications (Accepted 12 April 2021). - National paper: Pham-Ngoc, C., Tran, T. A., Tran, T. H., Vu, H. L., Pham Thi, P. L., and Ngo, T. H., 2020, Chemical compositions of amphiboles and their references to formation conditions of granitoids from Nam Rom and Song Ma massifs, Northwest Vietnam: Vietnam Journal of Earth Sciences, v. 42, p. 80-92. Tuan-Anh Tran, Trong-Hoa Tran, Can Pham-Ngoc, J. Gregory Shellnutt, Thuy T. Pham, Izokh A.E., Phuong-Lien T Pham, Petrology of the Permian-Triassic granitoids in Northwest Vietnam and their relation to the amalgamation of the Indochina and the Sino-Vietnam composite terranes: Vietnam Journal of Earth Sciences. |