Geochemistry of Cenozoic Basaltic Rocksaround Liuhe National Geopark, Jiangsu Province, Eastern China: Petrogenesis and Mantle Source

Authors: Yung-Tan Lee, Ren-Yi Huang, Ju-Chin Chen, Jyh-Yi Shih, Meng-Lung Lin, Hsiao-Ling Yu, Yen-Tsui Hu, Chih-Cheng Chen

Abstract:

Cenozoic basalts found in Jiangsu province of eastern China include tholeiites and alkali basalts. The present paper analyzed the major, trace elements, rare earth elements of these Cenozoic basalts and combined with Sr-Nd isotopic compositions proposed by Chen et al. (1990)[1] in the literatures to discuss the petrogenesis of these basalts and the geochemical characteristics of the source mantle. Based on major, trace elements and fractional crystallization model established by Brooks and Nielsen (1982)[2] we suggest that the basaltic magma has experienced olivine + clinopyroxene fractionation during its evolution. The chemical compositions of basaltic rocks from Jiangsu province indicate that these basalts may belong to the same magmatic system. Spidergrams reveal that Cenozoic basalts from Jiangsu province have geochemical characteristics similar to those of ocean island basalts(OIB). The slight positive Nb and Ti anomalies found in basaltic rocks of this study suggest the presence of Ti-bearing minerals in the mantle source and these Ti-bearing minerals had contributed to basaltic magma during partial melting, indicating a metasomatic event might have occurred before the partial melting. Based on the Sr vs. Nd isotopic ratio plots, we suggest that Jiangsu basalts may be derived from partial melting of mantle source which may represent two-end members mixing of DMM and EM-I. Some Jiangsu basaltic magma may be derived from partial melting of EM-I heated by the upwelling asthenospheric mantle or asthenospheric diapirism.

Keywords: Geochemistry, Jiangsu Province, Cenozoic basalts, Fractional crystallization.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1333646

References:

[1] D. G. Chen, H. T. Chou, C. T. Yang and Y. S. Wang, "Petrogenesis of Cenozoic volcanic rocks and isotopic characteristics of mantle sources in Shandong, Anhwei and Jiangsu provinces. The Characteristics and dynamics of upper mantle of China." Seismic Press, Beijing, pp. 124-131 , 1990.(in Chinese)
[2] C. K. Brooks and T. F. D. Nielsen, "The East Greenland continental margin: a transition between oceanic and continental magmatism." J. Geol. Soc. London 39,pp.265-275, 1982.
[3] X. L. Huang, Y. G. Xu and D. Y. Liu, "Geochronology, petrology and geochemistry of the granulite xenolith from Nushan, east China: Implication for a heterogeneous lower crust beneath the Sino-Korean Craton." Acta Geochimica et Cosmochimica, 68, pp.127-149, 2004.
[4] B. M. Jahn, B. Auvray, J. Cornichet, Y. L. Bai, Q. H. Shen and D. Y. Liu, " 3.5 Ga old amphibolites from eastern Hebei province, China: field occurrence, petrography, Sm-Nd isochron age and REE geochemistry." Precambrian Research, 34, pp.311-346, 1987.
[5] B. M. Jahn, "Origin of granulites: Geochemical constraints from archean granulite facies rocks of the Sino-Korean craton, China." In Vielzeuf , D. and Vidal, Ph. (eds), Granulites and Crustal Evolution. Kluwer Academic Publishers, Netherlands, pp. 471-492, 1990.
[6] R. X. Liu, W. J. Chen, J. Z. Sun and D. M. Li, "The K-Ar age and tectonic environment of Cenozoic volcanic rocks in China." In Liu, R. X., ed. The age and geochemistry of Cenozoic volcanic rocks in China. The Seismic Press, Beijing, pp. 1-43, 1992. (In Chinese).
[7] A. I. Okay and A. M. C. Sengör, "Evidence for intracontinental thrust-related exhumation of the ultra-high-pressure rocks in China." Geology, 20, pp.411-414, 1992.
[8] A. Yin and S. Y. Nie, "An indentation model for the North and South China collision and the development of the Tan-Lu and Honam fault systems, eastern Asia." Tectonics, 12, pp. 801-813, 1993.
[9] S. L. Chung, "Trace element and isotope characteristics of Cenozoic basalts around the Tanlu fault with implications for the eastern plate boundary between North and South China." Journal of Geology, 107,pp.301-312, 1999.
[10] Z. X. Li, "Collision between the North and South China blocks: a crustal-detachment model for suturing in the region east of the Tanlu fault." Geology, 22, pp.739-742, 1994.
[11] J. F. Ying, H. F. Zhang, N. Kita, Y. Morishita and, G. Shimoda, "Nature and evolution of Late Cretaceous lithospheric mantle beneath the eastern North China Craton: Constraints from petrology and geochemistry of peridotitic xenoliths from J├╝nan, Shandong Province, China." Earth and Planetary Science Letters, 244, pp.622-638, 2006.
[12] H. Zou, A. Zindler, X. Xu and Q. Qi, "Major, trace element, and Nd, Sr and Pb isotope studies of Cenozoic basalts in SE China: mantle sources, regional variations, and tectonic significance." Chemical Geology, 171, pp.33-47, 2000.
[13] D. Chen and Z. Peng, "K-Ar ages and Pb and Sr isotopic characteristics of Cenozoic volcanic rocks in Shandong, China." Geochimica, 5, pp.293-303, 1985. (in Chinese)
[14] J. Dostal, C. Dupuy, M. Z. Zhai and X. C. Zhi, "Geochemistry and origin of Pliocene alkali basaltic lavas from Anhui-Jiangsu, eastern China." Geochemical Journal, 22, pp.165-176, 1988.
[15] L. Wu, M. Zhai, X. Zheng, R. Yang and Z. Huang, "Cenozoic volcanic rocks in eastern China." Acta Petrologica Sinica, 1, pp.1-23, 1985. (in Chinese)
[16] Y. G. Xu and J. L. Bodinier, "Contrasting enrichments in high and low temperature xenoliths from Nushan, Eastern China: Results of a single metasomatic event during lithospheric accretion?" Journal of Petrology, 45, pp.321-341, 2004.
[17] T. N. Irvine and W. R. A. Baragar, " A guide to the chemical classification of the common rocks." Can. J. Earth Sci. 8, pp. 523-548, 1971.
[18] F. A. Frey and M. Prinz, "Ultramafic inclusions from San Carlos, Arizona: petrological and geochemical data bearing on their petrogenesis." Earth and Planetary Science Letters, 38, pp.129-176, 1978.
[19] J. F. G. Wilkinson and R. W. Le Maitre, "Upper mantle amphiboles and micas and TiO2, K2O, and P2O5 abundances and 100Mg/(Mg+Fe+2) ratios of common basalts and andesites: implications for modal mantle metasomatism and undepleted mantle compositions." Journal of Petrology, 28, pp.37-73, 1987.
[20] S. S. Sun and W. F. McDonough, "Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes." Journal Geological Society of London Special Publication, 42,pp.313-345, 1989.
[21] X. C. Zhi, Y. Song, F. A. Frey, J. Feng and M Zhai, "Geochemistry of Hannuoba basalts, eastern China: constraints on the origin of continental alkali and tholeiitic basalts." Chemical Geology, 88, pp.1-33, 1990.
[22] K. Tu, M. F. Flower, R. W. Carlson, M. Zhang and G. H. Xie, "Sr, Nd, and Pb isotopic compositions of Hainan basalts (south China): implications for a subcontinental lithosphere Dupal source." Geology, 19, pp.567-569, 1991.
[23] M. F. J. Flower, M. Zhang, C. Y. Chen, K. Tu and G. Xie, "Magmatism in the South China Basin, 2. Post-spreading Quaternary basalts from Hainan Island, South China." Chemical Geology, 97, pp.65-87, 1992.
[24] S. L. Chung, S. S. Sun, K. Tu, C. H. Chen and C. Y. Lee, "Late Cenozoic basaltic volcanism around the Taiwan Strait, SE China: product of lithosphere-asthenosphere interaction during continental extension." Chemical Geology, 112, pp.1-20, 1994.
[25] C. Q. Liu, A. Masuda and G. H. Xie, "Major- and trace-element compositions of Cenozoic basalts in eastern China: petrogenesis and mantle source." Chemical Geology, 114, pp.19-42, 1994.
[26] J. L. Bodinier, C. Merlet, R. M Bedini., F. Simien, R. Remaid and C. J. Carrido, "The distribution of niobium, tantalum, and other highly incompatible trace elements in the lithospheric mantle: the spinel paradox." Acta Geochimica et Cosmochimica, 60, pp.545-550, 1996.
[27] D. A. Ionov and A. W. Hofmann, "Nb-Ta-rich mantle amphiboles and micas: implications for subduction-related metasomatic trace element fractionations." Earth and Planetary Science Letters, 131, pp.341-356, 1995.
[28] F. Kalfoun, D. A. Ionov and C. Merlet, "HFSE residence and Nb-Ta ratios in metasomatised, rutile-bearing mantle peridotites." Earth and Planetary Science Letters, 199, pp.49-65, 2002.
[29] A. W. Hofmann, K. P. Joohum, M. Seufert and W. M. White, "Nb and Pb in oceanic basalts: new constraints on mantle evolution." Earth Planet. Sci. Lett. 79,pp.33-45, 1986.
[30] Y. Chen, Y Zhang., D. Graham, S. Su and J. Deng, "Geochemistry of Cenozoic basalts and mantle xenoliths in Northeast China." Lithos, 96, pp.108-126, 2007.
[31] A. Zindler and S. R. Hart, "Chemical geodynamics." Annual Review of Earth and Planetary Science, 14, pp.493-571, 1986.
[32] H. L. Zhao, "Neogene-Quaternary continental rifting volcanism and deep process in the southeast coast of China." China Geosciences University Press. (in Chinese)
[33] S. R. Hart, "Heterogeneous mantle domains: signatures, genesis and mixing chronologies." Earth Planet. Sci. Lett. 90, pp.273-296, 1988.
[34] B. L. Weaver, "The origin of oceanic island basalt endmember. Compositions: trace element and isotopic constraints." Earth and Planetary Science Letters, 104, pp.381-397, 1991.
[35] M. Meschede, "A method of discriminating between different types of Mid-ocean ridge basalts and continental tholeiites with the Nb-Zr-Y diagram." Chem. Geol. 56,pp.207-218, 1986.