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洋中脊火山玻璃代表地幔源区熔体成分,携带了岩浆作用和洋壳形成的大量信息。通过研究太平洋洋中脊火山玻璃的主量元素地球化学特征,探讨了岩浆作用过程的元素分配特征,结果表明:洋中脊火山玻璃的主量元素成分呈现规律性演化,从基性向中酸性演化过程中,Na_2O的含量从2%逐渐升高至6%,K_2O从<1%逐渐升高至5%;而Ca O含量从10%~13%逐渐降低至1%,Fe O从9%~13%逐渐降低至3%,Al_2O_3从18%逐渐降低至13%。洋中脊火山玻璃中主量元素分配特征揭示了其分配的不均一性,这可能是受到宏观上地幔不均一性的影响;在同一洋中脊中的火山玻璃成分也存在不均一性,可能是岩浆作用过程中局部动力学机制差异引起的元素分配不均一。
Mid-oceanic ridge volcanic glass represents the melt composition of the mantle source zone and carries extensive information of magmatism and oceanic crust formation. By studying the elemental and geochemical features of the mid-ocean ridge mid-oceanic volcanic rocks, the elemental distribution characteristics of magmatic processes are discussed. The results show that the main elements of volcanic mid-oceanic ridge show a regular evolution from basic to moderately acidic In the process, the content of Na 2 O gradually increased from 2% to 6%, K 2 O gradually increased from <1% to 5%, while the content of CaO gradually decreased from 10% to 13% to 1% 13% gradually reduced to 3%, Al 2 O 3 gradually reduced from 18% to 13%. The distribution characteristics of major elements in mid-oceanic ridge volcanic glass reveal the heterogeneity of their distribution, which may be affected by the heterogeneity of the upper mantle. The composition of volcanic glass in the same mid-ocean ridge may also be heterogeneous. Is the magmatic process of local dynamics caused by differences in the distribution of elements of non-uniform.