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Continental flood basalts are thought to be the volcanic manifestations of large volumes of magma derived from Earths mantle including mantle compositions with variable elemental and isotopic compositions(Zhang et al.,2006; Hooper et al.,2007; Sobolev et al.,2009,2011).Understanding the compositional record of continental flood basalts is thus crucial for a better understanding of mantle compositional variations and ultimately the dynamics that lead to these variations.Radiogenic isotope systematics of melts derived from a mantle source may provide clues on the formation mechanisms(e.g.,plume versus nonplume)of continental flood basalts.Isotopic compositions of continental flood basalts are essential to understand their genesis and to constrain the character of their mantle sources.Because of potential crustal contamination,it needs to be evaluated if and to which degree these basalts record primitive isotopic signals of their mantle sources and/or crustal signatures.This study examines the Sr,Nd,Hf,and Pb isotopic compositions of the late Cenozoic Xinchang-Shengzhou(XS)flood basalts,a small-scale continental flood basalt field in eastern China.The basalts show positive correlations between 87Sr/86Sr and 143Nd/144Nd,and negative correlations between 143Nd/144Nd and 176Hf/177Hf,which deviate from compositional arrays of crustal contamination and instead highlight variations in magmatic recharge intensity and mantle source compositions.The lava samples formed by high-volume magmatic recharge recorded signals of recycled sediments in the mantle source,which are characterized by moderate Ba/Th(91.9–106.5),excess 208Pb/204Pb relative to 206Pb/204Pb,and excess 176Hf/177Hf relative to 143Nd/144Nd.Thus,we propose that magmatic recharge buffers the original isotopic compositions of magmas against crustal contamination.Identifying and utilizing the isotope systematics of continental flood basalts generated by high volumes of magmatic recharge is thus crucial to trace their mantle sources.