运用离子探针技术测定了河北汉诺坝新生代玄武岩中 3个单斜辉石巨晶的氢同位素组成 ,结果显示同一颗粒内部表现出微尺度的不均一性 ,2 mm范围内 δD的变化达到 6 0‰。δD和氢含量之间不存在同步的变化 ,巨晶内部的化学成分均一 ,因此我们认为巨晶的氢同位素不均一性继承自母岩浆。母岩浆的氢同位素变化可能是去气过程中气相与熔体之间的分馏引起的。单斜辉石巨晶形成后很短的时间内即被寄主岩浆带至地表并经历了快速淬火。 The isotopic compositions of three clinopyroxene megacrysts in the Cenozoic basalts of Hannuoba, Hebei Province, China were determined by ion probe technique. The results showed that the same particles showed inhomogeneity at the microscale, with a change of δD within 2 mm ‰. There is no synchronous change between δD and hydrogen content, and the chemical composition within the giant crystal is uniform. Therefore, we believe that the heterogeneity of hydrogen isotope of giant crystal inherited from the parent magma. The change of hydrogen isotope of the parent magma may be caused by the fractionation between the gas phase and the melt in the degassing process. After a short period of time after the formation of clinopyroxene, the host magma was brought to the surface and experienced rapid quenching.