Geochemistry, zircon U-Pb age and Hf isotopic constraints on the petrogenesis of the Silurian rhyolites in the Loei fold belt and their tectonic implications

Abstract

Zircon U-Pb dating, Lu-Hf isotopic and geochemical data for the Silurian rhyolites from the Loei fold belt are presented to constrain their petrogenesis and tectonic settings. The rhyolites give a weighted mean ²⁰⁶Pb/²³⁸U age of 423.7±2.7 Ma, and are characterized by high SiO₂, Al₂O₃, K₂O and low MnO, MgO and P₂O₅. All samples are enriched in LILEs (e.g., Ba, K, Pb) and LREEs and depleted in HFSEs (e.g., Nb, Ta, Ti) with obvious negative Eu-anomalies (dEu=0.56–0.63). The calc-alkaline rhyolites are typical arc-related rocks. The Loei rhyolites have high A/CNK ratios (1.19–1.34) and positive ε _Hf(t) (4.03–5.38), which can be interpreted as partial melting of juvenile crustal materials followed by multistage melting and differentiation, similar to highly fractional I-type rocks. Combined with regional geological surveys, the Loei rhyolites should be formed in a volcanic arc environment and may be in contact with the Truong Son fold belt during the Early Paleozoic. Moreover, the Simao Block might be in contiguity with the Indochina Block during Silurian.

Keywords

I-type rhyolite / zircon U-Pb dating / Hf isotopic composition / geochemical characteristics / Loei fold belt / Indochina Block

References

Barr S. M., Macdonald A. S., Ounchanum P., . Age, Tectonic Setting and Regional Implications of the Chiang Khong Volcanic Suite, Northern Thailand.. Journal of the Geological Society, 2006, 163(6): 1037-1046.

Boonsoong A., Panjasawatwong Y., Metparsopsan K. Petrochemistry and Tectonic Setting of Mafic Volcanic Rocks in the Chon Daen-Wang Pong Area, Phetchabun, Thailand.. Island Arc, 2011, 20(1): 107-124.

Bunopas S., Vella P. Geological Society of Thailand and Geological Society of Malaysia. Tectonic and Geologic Evolution of Thailand Proceedings of the Workshop on Stratigraphic Correlation of Thailand and Malaysia, 1983, 212-232.

Burrett C., Zaw K., Meffre S., . The Configuration of Greater Gondwana–Evidence from LA-ICPMS, U-Pb Geochronology of Detrital Zircons from the Palaeozoic and Mesozoic of Southeast Asia and China.. Gondwana Research, 2014, 26(1SI): 31-51.

Cawood P. A., Wang Y. J., Xu Y. J., . Locating South China in Rodinia and Gondwana: A Fragment of Greater India Lithosphere. Geology, 2013, 41(8): 903-906.

Chappell B. W. Aluminium Saturation in I- and S-Type Granites and the Characterization of Fractionated Haplogranites.. Lithos, 1999, 46(3): 535-551.

Charoenprawat A., Wongwanich T., Tantiwanit W., . Geological Map of Thailand 1: 250 000 Sheet Changwat Loei, 1976 Bangkok: Department of Mineral Resources

Chonglakmani C., Helmcke D. Geodynamic Evolution of Loei and Phetchabun Regions—Does the Discovery of Detrital Chromian Spinels from the Nam Duk Formation (Permian, North-Central Thailand) Provide New Constraint. Gondwana Research, 2001, 4(3): 437-442.

Condie K. C. Geochemical Changes in Baslts and Andesites across the ArcheanProterozoic Boundary: Identification and Significance.. Lithos, 1989, 23(1/2): 1-18.

Dong M. L., Dong G. C., Mo X. X., . Geochemistry, Zircon U-Pb Geochronology and Hf Isotopes of Granites in the Baoshan Block, Western Yunnan: Implications for Early Paleozoic Evolution along the Gondwana Margin.. Lithos, 2013, 179: 36-47.

Feng Q. L., Chonglakmani C., Helmcke D., . Correlation of Triassic Stratigraphy between the Simao and Lampang-Phrae Basins: Implications for the Tectonopaleogeography of Southeast Asia.. Journal of Asian Earth Sciences, 2005, 24(6): 777-785.

Gong S. L., Chen N. S., Geng H. Y., . Zircon Hf Isotopes and Geochemistry of the Early Paleoproterozoic High-Sr Low-Y Quartz-Diorite in the Quanji Massif, NW China: Crustal Growth and Tectonic Implications.. Journal of Earth Science, 2014, 25(1): 74-86.

Harris N. B. W., Pearce J. A., Tindle A. G. Geochemical Characteristics of Collision-Zone Magmatism.. Geological Society, London, Special Publications, 1986, 19(1): 67-81.

Hoskin P. W., Schaltegger U. The Composition of Zircon and Igneous and Metamorphic Petrogenesis.. Reviews in Mineralogy and Geochemistry, 2003, 53(1): 27-62.

Hu Z. C., Liu Y. S., Gao S., . Improved In Situ Hf Isotope Ratio Analysis of Zircon Using Newly Designed X Skimmer Cone and Jet Sample Cone in Combination with the Addition of Nitrogen by Laser Ablation Multiple Collector ICP-MS.. Journal of Analytical Atomic Spectrometry, 2012, 27(9): 1391-1399.

Hutchison C. S. Geological Evolution of South-East Asia, 1989 Oxford: Clarendon Press

Intasopa S., Dunn T. Petrology and Sr-Nd Isotopic Systems of the Basalts and Rhyolites, Loei, Thailand.. Journal of Southeast Asian Earth Sciences, 1994, 9(1): 167-180.

Irvine T., Baragar W. A Guide to the Chemical Classification of the Common Volcanic Rocks.. Canadian Journal of Earth Sciences, 1971, 8(5): 523-548.

Ji W. Q., Wu F. Y., Chung S. L., . Zircon U-Pb Geochronology and Hf Isotopic Constraints on Petrogenesis of the Gangdese Batholith, Southern Tibet.. Chemical Geology, 2009, 262(3/4): 229-245.

Jungyusuk N., Khositanont S. Piencharoen C. Volcanic Rocks and Associated Mineralization in Thailand. Proceedings of the National Conference on Geologic Resources of Thailand: Potential for Future Development, 1992 Bangkok: Department of Mineral Resources, 528-532.

Kamvong T., Zaw K., Meffre S., . Adakites in the Truong Son and Loei Fold Belts, Thailand and Laos: Genesis and Implications for Geodynamics and Metallogeny.. Gondwana Research, 2014, 26(1): 165-184.

Kelemen P. B., Hanghøj K., Greene A. R. One View of the Geochemistry of Subduction-Related Magmatic Arcs, with an Emphasis on Primitive Andesite and Lower Crust.. Treatise on Geochemistry, 2003, 3: 593-659.

Khositanont S., Panjasawatwong Y., Ounchanum P., . Petrochemistry and Zircon Age Determination of Loei-Phetchabun Volcanic Rocks. Proceedings of the International Symposia on Geoscience Resources and Environments of Asian Terranes (GREAT 2008), Bangkok, 2008, 272-280.

Kinny P. D., Maas R. Lu-Hf and Sm-Nd Isotope Systems in Zircon.. Reviews in Mineralogy and Geochemistry, 2003, 53(1): 327-341.

Lan C. Y., Chung S. L., Van Long T., . Geochemical and Sr-Nd Isotopic Constraints from the Kontum Massif, Central Vietnam on the Crustal Evolution of the Indochina Block.. Precambrian Research, 2003, 122(1): 7-27.

Le Bas M. J., Le Maitre R. W., Streckeisen A., . A Chemical Classification of Volcanic Rocks Based on the Total Alkali-Silica Diagram.. Journal of Petrology, 1986, 27(3): 745-750.

Lehmann B., Zhao X. F., Zhou M. F., . Mid-Silurian Back-Arc Spreading at the Northeastern Margin of Gondwana: The Dapingzhang Dacite-Hosted Massive Sulfide Deposit, Lancangjiang Zone, Southwestern Yunnan, China.. Gondwana Research, 2013, 24(2): 648-663.

Li X. H., Li Z. X., Li W. X., . U-Pb Zircon, Geochemical and Sr-Nd-Hf Isotopic Constraints on Age and Origin of Jurassic I- and A-Type Granites from Central Guangdong, SE China: A Major Igneous Event in Response to Foundering of a Subducted Flat-Slab. Lithos, 2007, 96(1/2): 186-204.

Liu H. C., Wang Y. J., Fan W. M., . Petrogenesis and Tectonic Implications of Late-Triassic High ?Nd(t)-?Hf(t) Granites in the Ailaoshan Tectonic Zone (SW China).. Science China: Earth Sciences, 2014, 57(9): 2181-2194.

Liu Y. S., Gao S., Hu Z. C., . 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, 2009, 51(1/2): 537-571.

Liu Y. S., Hu Z. C., Zong K. Q., . Reappraisement and Refinement of Zircon U-Pb Isotope and Trace Element Analyses by LA-ICP-MS.. Chinese Science Bulletin, 2010, 55(15): 1535-1546.

Liu Y. S., Zong K. Q., Kelemen P. B., . 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, 2008, 247(1): 133-153.

Ludwig K. R. User’s Manual for Isoplot 3.00: A Geochronological Toolkit for Microsoft Excel, 2003 Berkeley: Berkeley Geochronology Center Special Publication, 1-74.

Maniar P. D., Piccoli P. M. Tectonic Discrimination of Granitoids.. Geological Society of America Bulletin, 1989, 101(5): 635-643.

Mao X. C., Wang L. Q., Li B., . Discovery of the Late Silurian Volcanic Rocks in the Dazhonghe Area, Yunxian-Jinggu Volcanic Arcbelt, Western Yunnan, China and Its Geological Significance.. Acta Petrologica Sinica, 2012, 28(5): 1517-1528.

Metcalfe I. Gondwana Dispersion and Asian Accretion: Tectonic and Palaeogeographic Evolution of Eastern Tethys.. Journal of Asian Earth Sciences, 2013, 66: 1-33.

Nagy E. A., Maluski H., Lepvrier C., . Geodynamic Significance of the Kontum Massif in Central Vietnam: Composite ⁴⁰Ar/³⁹Ar and U-Pb Ages from Paleozoic to Triassic.. The Journal of Geology, 2001, 109: 755-770.

Nakano N., Osanai Y., Owada M., . Tectonic Evolution of High-Grade Metamorphic Terranes in Central Vietnam: Constraints from Large-Scale Monazite Geochronology.. Journal of Asian Earth Sciences, 2013, 73: 520-539.

Panjasawatwong Y., Zaw K., Chantaramee S., . Geochemistry and Tectonic Setting of the Central Loei Volcanic Rocks, Pak Chom Area, Loei, Northeastern Thailand.. Journal of Asian Earth Sciences, 2006, 26(1): 77-90.

Pearce J. A., Harris N. B., Tindle A. G. Trace Element Discrimination Diagrams for the Tectonic Interpretation of Granitic Rocks.. Journal of Petrology, 1984, 25(4): 956-983.

Peter G. L., Silver L. T. Rare Earth Element Distributions among Minerals in a Granodiorite and Their Petrogenetic Implications.. Geochimica et Cosmochimica Acta, 1983, 47(5): 925-939.

Qi X. X., Santosh M., Zhu L. H., . Mid-Neoproterozoic Arc Margin of the Indochina Block, SW China: Geochronological and Petrogenetic Constraints and Implications for Gondwana Assembly.. Precambrian Research, 2014, 245: 207-224.

Qian X., Feng Q. L., Chonglakmani C., . Geochemical and Geochronological Constrains on the Chiang Khong Volcanic Rocks (Northwestern Thailand) and Its Tectonic Implications.. Frontiers of Earth Science, 2013, 7(4): 508-521.

Qian X., Feng Q. L., Wang Y. J., . Arc-Like Volcanic Rocks in NW Laos: Geochronological and Geochemical Constraints and Their Tectonic Implications.. Journal of Asian Earth Sciences, 2015, 98: 342-357.

Roger F., Leloup P. H., Jolivet M., . Long and Complex Thermal History of the Song Chay Metamorphic Dome (Northern Vietnam) by Multi-System Geochronology.. Tectonophysics, 2000, 321(4): 449-466.

Salam A., Zaw K., Meffre S., . Geochemistry and Geochronology of the Chatree Epithermal Gold-Silver Deposit: Implications for the Tectonic Setting of the Loei Fold Belt, Central Thailand.. Gondwana Research, 2014, 26(1): 198-217.

Shi M. F., Lin F. C., Fan W. Y., . Zircon U-Pb Ages and Geochemistry of Granitoids in the Truong Son Terrane, Vietnam: Tectonic and Metallogenic Implications.. Journal of Asian Earth Sciences, 2015, 101: 101-120.

Sisson T. W., Ratajeski K., Hankins W. B., . Voluminous Granitic Magmas from Common Basaltic Sources.. Contributions to Mineralogy and Petrology, 2005, 148(6): 635-661.

Sun S. S., McDonough W. F. Chemical and Isotopic Systematics of Oceanic Basalts: Implications for Mantle Composition and Processes.. Geological Society, London, Special Publications, 1989, 42(1): 313-345.

Sylvester P. J. Post-Collisional Strongly Peraluminous Granites.. Lithos, 1998, 45(1): 29-44.

Tao J. H., Li W. X., Li X. H., . Petrogenesis of Early Yanshanian Highly Evolved Granites in the Longyuanba Area, Southern Jiangxi Province: Evidence from Zircon U-Pb Dating, Hf-O Isotope and Whole-Rock Geochemistry.. Science China Earth Sciences, 2013, 56(6): 922-939.

Tran H. T., Zaw K., Halpin J. A., . The Tam Ky-Phuoc Son Shear Zone in Central Vietnam: Tectonic and Metallogenic Implications.. Gondwana Research, 2014, 26(1): 144-146.

Udchachon M., Thassanapak H., Feng Q. L., . Geochemical Constraints on the Depositional Environment of Upper Devonian Radiolarian Cherts from Loei, North-Eastern Thailand.. Frontiers of Earth Science, 2011, 5(2): 178-190.

Vivatpinyo J., Charusiri P., Sutthirat C. Volcanic Rocks from Q-Prospect, Chatree Gold Deposit, Phichit Province, North Central Thailand: Indicators of Ancient Subduction.. Arabian Journal for Science and Engineering, 2014, 39(1): 325-338.

Wang Q. F., Deng J., Li C., . The Boundary between the Simao and Yangtze Blocks and Their Locations in Gondwana and Rodinia: Constraints from Detrital and Inherited Zircons.. Gondwana Research, 2014, 26(2): 438-448.

Wang Y., Zhang Y., Fan W., . Early Neoproterozoic Accretionary Assemblage in the Cathaysia Block: Geochronological, Lu-Hf Isotopic and Geochemical Evidence from Granitoid Gneisses.. Precambrian Research, 2014, 249: 144-161.

Whalen J. B., Currie K. L., Chappell B. W. A-Type Granites: Geochemical Characteristics, Discrimination and Petrogenesis.. Contributions to Mineralogy and Petrology, 1987, 95(4): 407-419.

Winchester J. A., Floyd P. A. Geochemical Discrimination of Different Magma Series and Their Differentiation Products Using Immobile Elements.. Chemical Geology, 1977, 20: 325-343.

Wu F. Y., Jahn B., Wilde S. A., . Highly Fractionated I-Type Granites in NE China (I): Geochronology and Petrogenesis.. Lithos, 2003, 66(3): 241-273.

Wu F. Y., Jahn B., Wilde S. A., . Highly Fractionated I-Type Granites in NE China (II): Isotopic Geochemistry and Implications for Crustal Growth in the Phanerozoic.. Lithos, 2003, 67(3/4): 191-204.

Zhang D. H., Wei J. H., Fu L. B., . Formation of the Jurassic Changboshan-Xieniqishan Highly Fractionated I-Type Granites, Northeastern China: Implication for the Partial Melting of Juvenile Crust Induced by Asthenospheric Mantle Upwelling.. Geological Journal, 2013, 50(2): 122-138.

Zhao S., Xu W. L., Wang W., . Geochronology and Geochemistry of Middle-Late Ordovician Granites and Gabbros in the Erguna Region, NE China: Implications for the Tectonic Evolution of the Erguna Massif.. Journal of Earth Science, 2014, 25(5): 841-853.

Zhu D. C., Zhao Z. D., Niu Y. L., . Cambrian Bimodal Volcanism in the Lhasa Terrane, Southern Tibet: Record of an Early Paleozoic Andean-Type Magmatic Arc in the Australian Proto-Tethyan Margin.. Chemical Geology, 2012, 328: 290-308.