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The microstructures of the mantle tectonites in the Zunhua Neoarchean ophiolitic mlange are mainly coarse-mosaicstructures with locally interstitial impregnated melts. Olivine and orthopyroxene occur as residual porphyroclastic blasts, dynamic recrys-tallization neoblasts or elongated to be tabular. The podiform chromitites are mostly strongly deformed with the development of pull-apartstructure. These microstructures are typical high-temperature plastic deformation in oceanic upper mantle resulting from ocean-floorspreading. Besides the high-temperature plastic deformation, undeformed magmatic intrusions such as undeformed podiform chromitite,dunite and pyroxenite intrusions are also preserved in the mantle tectonite. Structures of high-temperature plastic deformation and intensivemagmatic activity prove that the Zunhua ophiolite was formed under fast spreading oceanic ridge, similar to the Oman ophiolite. And themicrostructures of country rocks, such as quartz ribbon, core and mantle structure, dynami
The microstructures of the mantle tectonites in the Zunhua Neoarchean ophiolitic mlange are mainly coarse-mosaicstructures with locally interstitial impregnated melts. Olivine and orthopyroxene occur as residual porphyroclastic blasts, dynamic recrys-tallization neoblasts or elongated to be tabular. The podiform chromitites are particularly with the development of pull-apartstructure. These microstructures are typical high-temperature plastic deformation in oceanic upper mantle resulting from ocean-floorspreading. preserved in the mantle tectonite. Structures of high-temperature plastic deformation and intensivemagmatic activity prove that the Zunhua ophiolite was formed under fast spreading oceanic ridge, similar to the Oman ophiolite. And themicrostructures of country rocks, such as quartz ribbon, core and mantle structure, dynami