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The development of Yichun City, Heilongjiang Province, wuyiling a Mesozoic volcanic rocks. Petrological, geochemical and zircon SHRIMP U-Pb age analysis of the papers on this set of volcanic rocks. Through these studies, clear set of volcanic lithological features and rock series vesting formation era determined to Mei Fung group, identify the geochemical characteristics of magma source and nature of deep geological role in the process, and to explore the the Volcanic Rocks wuyiling this. Meifeng volcanic rocks of SHRIMP U-Pb zircon age of 105 ± 1.5Ma, times vested in the late Early Cretaceous. Rock SiO2 content of 51.27% -70.13%, 3.9% -9.6% Total alkali content (Na2O K2O), potassium-rich, its w (Na2O) / w (K20) of 0.3-2.5, poor titanium, w (Ti2O ) of 0.04% -1.9%, the aluminum content is high, but the large variation range, w (A1203) = 14.05% -18.24%. Combined with TAS vote diagram Na2O, K2O relative content (Na2O-2.0 ≤ K2O), for the first time confirmed its typical shoshonitic series, the main rock types the potassium trachybasalt, shoshonite, security coarse rock and trachyte. All samples show enrichment of LREE and HREE loss as well as the obvious negative Eu anomalies. Trace elements exhibit large ion lithophile elements such as Cs, Rb, Ba, Th relatively strongly enriched relative loss of high field strength elements Ta, Ti elements of extreme loss. Mantle-derived magma oceanic crust and marine sediments involved in the process of evolution, but also clearly influenced by ancient Asian Domain granite assimilation. Volcanic magma experienced in the evolution process of fractional crystallization of olivine, Ca-rich pyroxene, plagioclase. Combined with the previous volcanic rocks in the region to learn and geochemical studies, the paper argues that the formation of the the Meifeng group volcanic rocks is smaller due to the western Pacific plate subduction in mainland China Northeast Asia under the subduction deeper level, foreign shell due to dehydration melting of melt or fluid, and to participate in marine sediments, this melt or fluid migration upward, accountable to the overlying mantle, induced partial melting of the mantle, enriched in large ion lithophile elements and light rare earth elements, upper crustal material contamination has obviously been in the process of magma ascent and experienced fractional crystallization of magmatic evolution, eventually leading to full of silicon, alkali shoshonitic magma was erupted.
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