【摘要】 对太平洋 １７８７ 柱沉积物样品进行了碎屑组分、分布、来源及组合的研究。结果表明，沉积物中的碎屑组分主要是生物来源、海洋自生来源和岩源。重组分以铁锰微结核、生物磷灰石、褐铁矿、磁铁矿、辉石类为主， 轻组分主要是生物蛋白石 （放射虫、海绵骨针等硅质生物壳体或骨骼）、粘土团集物和火山玻璃。根据各碎屑组分在整个柱芯的分布特点及其组合类型的不同， 把 １７８７ 柱分为 ６ 层， 并大致反映沉积环境的氧化还原条件、火山活动特点及底层流活动状况。研究结果能与磁性地层资料、地球化学资料和沉积物构造相互印证， 表明碎屑组分及其组合研究能为恢复沉积环境提供矿物学证据。更多还原

【Abstract】 Studies on the clastic components and their assemblages of the sediments in Core 1787 from the East Pacific Ocean shows that the heavy clastic components are mainly ferromanganese micro\|nodules, bio\|apatite, limonite, magnetite, pyroxene, while the light ones are mainly bio\|opal (siliceous biotesta, such as radiolaria and sponge\|spicule), clay aggregates and volcanic glass According to their distribution and assemblages, the Core 1787 can be divided into 6 strata, and the oxidation \| reduction conditions, vocanic activities and bottom current of the sedimentary environment can be roughtly reflected For example, in the sedimentation periods of 0~2 5 cm and 570~690 cm, the sedimentary environment was oxidative by reason of the activity of Antarctic bottom water, where the content of limonite is high, and the sediments are rich in bioturbation structure In 270~570 cm, the volcanic components increased apparently in the sediments, and the content of organic carbon is low It is implied that the volcano was active and the volcano activity may bring about the change of oceanic environment and lead to the decrease of bio\|productivity The results are coincided with magnetostratigraphic data, geochemistry data and sediment strcture It is suggested that clastic components and their assemblages can provide mineralogic evidences to reconstruct sedimentary environment更多还原