U-Pb zircon LA-ICP-MS and Hf composition in granitogneiss of Chu Lai body and its implication of the Kontum massif, central Vietnam
- Authors: Trong Huu Nguyen 1*, Dung Tien Le 1, Ban Xuan To 1, Anh Van Thi Pham 1, Thanh Xuan Ngo 1, Nhu Thanh Ha 1, Ly Ly Thi Nguyen 2
1 Hanoi University of Mining and Geology, Hanoi, Vietnam
2 Vietnam Insitutute of Geosciences and Mineral Resources, Hanoi, Vietnam
- Received: 16th-Oct-2021
- Revised: 23rd-Jan-2022
- Accepted: 21st-Mar-2022
- Online: 31st-Aug-2022
- Field: Geology - Mineral
The Chu Lai granitogneiss is widespread throught the Northern Kontum massif. The Chu Lai body is located in the W-SW of the Nui Thanh Townlet (Nui Thanh Dists., Quang Nam Prov.). On an areas of ~ 300 km2. The Chu Lai intrusion mainly consists two mica gneiss, it is light grey and have porphyritic textures. Its major minerals include plagioclase (25÷40%), K-feldpar (20÷40%), quartz (25÷35%), biotite (5÷13%) and mustcovite (0÷6%). Accessory minerals are apatite, zircon, orthit. Garnet and tourmaline are occiasionally found. Zircons separated from a granitogneiss sample colleted in Chu Lai body are generally euhedral to subhedral, dark gray and prissmatic in shape with 100÷300 µm, with length/witdth ratios from 1:1÷1:3. There are many Neoproterozoic - Cambrian ages among the zircon cores in the Chu Lai samples, and these are regarded as inherited zircons. The LA-ICP-MS zircon age is 431 Ma, corresponding to the Silurian. The Chu Lai granitogneiss strongly negative zircon εHf (-4.2÷-11.4) and complex inherited zircon components, characteristics of typical S-type granite. Hf model ages TDM2 1.5÷1.9 Ga, suggests that the Chu Lai granitogneiss was derived from partial melting of old crustal basement rocks, probaly Paleoproterozoic in age.
Dinh, Q.S. (2017). Petrographic characteristics and zircon U-Pb geochronology of granite gneiss rocks in the Chu Lai - Kham Duc area (Quang Nam province). VNUHCM Journal of Natural Sciences, Vol. 1, No. 6, pp. 258-272. (in Vietnamese)
Hieu, P.T., Dung, N.T., Thuy, N.T.B., Minh, N.T., and Minh, P. (2016). U-Pb ages and Hf isotopic composition of zircon and bulk rock geochemistry of the Dai Loc granitoid complex in Kon Tum massif: Implications for early Paleozoic crustal evolution in central Vietnam. Journal of Mineralogical and Petrological Sciences, Vol. 111, No. 5, pp. 326-336.
Hoffet, J.H. (1935). Geological map of Indochina at scale 1: 500,000, No.12 of Da Nang sheet with explanations written according to the works of H. Counillon. R., Bourret and Hoffet, Publishing: SGI, Hanoi.
Liu, Y., Zong, K., Kelemen, P.B., and Gao, S. (2008). Geochemistry and magmatic history of eclogites and ultramafic rocks from the Chinese continental scientific drill hole: Subduction and ultrahigh-pressure metamorphism of lower crustal cumulates. Chemical Geology, Vol. 247, No. 1, pp. 133-153.
Liu, Y., Gao, S., Hu, Z., Gao, C., Zong, K., and Wang, D. (2010). Continental and oceanic crust recycling-induced melt–peridotite interactions in the Trans-North China Orogen: U–Pb dating, Hf isotopes and trace elements in zircons from mantle xenoliths. Journal of petrology, Vol. 51, No. 1-2, pp. 537-571.
Minh, N.T., Dung, N.T., Hung, D.D., Minh, P., Yu, Y., and Hieu, P.T. (2020). Zircon U-Pb ages, geochemistry, and isotopic characteristics of the Chu Lai granitic pluton in the Kontum massif, central Vietnam. Mineralogy and Petrology, Vol. 114, No. 4, pp. 289-303.
Nagy, E.A., Maluski, H., Lepvrier, C., Schärer, U., Thi, P.T., Leyreloup, A., and Thich, V.V. (2001). Geodynamic significance of the Kontum massif in central Vietnam: composite 40Ar/39Ar and U-Pb ages from Paleozoic to Triassic. The Journal of Geology, Vol. 109, No. 6, pp. 755-770.
Nguyen, H.T., Le, T.D., Pham, T.H. (2018). U-Pb zircon LA-ICP-MS and Hf composition in andesite of Ru Ri pass - Nha Trang and its geological significance. Vietnam Journal of Science and Technology, Vol. 60, No. 3, pp. 1-6. (in Vietnamese)
Tran, H., Zaw, K., Halpin, J.A., Manaka, T., Meffre, S., Lai, C.K., Lee, Y., Le, H.V., Dinh, S. (2014). The Tam Ky - Phuoc Son shear zone in Central Vietnam: tectonic and metallogenic implications. Gondwana Res, Vol. 26, No. 1, pp. 144-164.
Trinh, T.L., Tran, T.H., Nguyen, H.H., Bui, H.B., and Carter, A. (2019). New results of the study on isotopic age of the Granodiorite of Chu Lai Complex in North Eastern Quang Ngai by U-Pb zircon isotope dating method. Journal of Mining and Earth Sciences, Vol. 60, No. 1, pp. 7-14. (in Vietnamese)
Trong, N.H., Zong, K., Liu, Y., Yuan, Y., Hieu, P.T., Dung, L.T., and Minh, P. (2021). Early Paleozoic Arc Magmatism and Accretionary Orogenesis in the Indochina Block, Southeast Asia. The Journal of Geology, Vol. 129, No. 1, pp. 33-48.
Jiang, W., Yu, J.H., Wang, X., Griffin, W.L., Pham, T., Nguyen, D., and Wang, F. (2020). Early Paleozoic magmatism in northern Kontum Massif, Central Vietnam: Insights into tectonic evolution of the eastern Indochina Block. Lithos, Vol. 376, 105750.