Yichun City, Heilongjiang Province, Mei Fung wuyiling regional geochemistry of volcanic rocks and genetic analysis

Title: Yichun City, Heilongjiang Province, Mei Fung wuyiling regional geochemistry of volcanic rocks and genetic analysis
　　Author: Panrong
　　Degree-granting units: Chang'an University
　　Keywords: wuyiling region;; Mei Fung Group;; shoshonitic series;; geochemistry;; Analysis
　　Summary:
　　Yichun City, Heilongjiang Province, developed a set of regions wuyiling Mesozoic volcanic rocks. This thesis was on the set of volcanic rocks, geochemistry and SHRIMP U-Pb zircon age of analysis. These studies provide a clear set of volcanic Neodymium magnets lithology and rock series of ownership, the formation of specific times, to determine the abundance of groups for the United States to identify their geochemical characteristics, analysis of the magma source and the nature and role of deep geological process, while this region of the wuyiling causes of volcanic rocks.
　　Abundance of volcanic rocks of the United States SHRIMP U-Pb zircon age of 105 ± 1.5Ma, the late Early Cretaceous age attribution. Rock samples of SiO2 51.27% -70.13% for the whole alkali (Na2O + K2O) content of 3.9% -9.6%, K-rich, the w (Na2O) / w (K20) is 0.3-2.5, poor titanium, w ( Ti2O) 0.04% -1.9% range of aluminum content is high, but large, w (A1203) = 14.05% -18.24%. Investment plans with TAS and Na2O, K2O relative content (Na2O-2.0 ≤ K2O), first recognized it as a typical shoshonitic series, the main rock type potassium trachybasalt, olives mysterious crude rock, and latite trachyte. All samples show enrichment of light rare earth elements and heavy rare earth elements and obvious losses of negative Eu anomalies. Trace elements show Cs, Rb, Ba, Th and other large ion lithophile elements relative to the strong enrichment of high field strength elements relative loss of Ta, Ti elements of extreme loss. Mantle-derived magma evolution processes in oceanic crust and marine sediments in the material, but also significantly by the Paleo-Asian domain granite assimilation effect. Volcanic magma in the process of evolution has undergone olivine, Ca-rich pyroxene, plagioclase fractional crystallization.
　　With previous study on the local volcanic rock, rock geochemistry, the paper that the formation of the United States is the abundance of volcanic rocks of the western Pacific plate at a slight angle subduction under the Chinese mainland Northeast http://www.chinamagnets.biz/Neodymium/Ball-Neodymium-Magnets.php Asia, with dive deeper level, foreign shell due to dehydration melting of melt or fluid, and participate in marine sediments, such melts or fluids migrating upward, account of the overlying mantle, induced partial melting of the mantle, enriched in large ion lithophile elements and light rare earth elements, by magma rising significantly during the upper crustal materials, and experienced fractional crystallization, resulting in highly magmatic evolution of silicon, alkaline shoshonitic magma spray the surface.
　　Degree Year: 2010