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铁锰结壳样品中Sr含量随时间的演化曲线与深部海水δ18O曲线具有相似变化趋势.尤其是1Ma以来,两者皆以约100 ka的周期变化,与地球轨道偏心率的变化周期相符合.表明至少晚第四纪以来,铁锰结壳中Sr含量随时间演化曲线可以示踪古气候变化.影响铁锰结壳中Sr含量变化的几种因素:由间冰期向冰期转化,海平面下降引起近海区域的碳酸盐溶解、海水量减少导致海洋中Sr的含量升高、海洋表层生物生产率增加淡表层海水中Sr随生物尸体向深部海水迁移、海洋中碳酸盐补偿深度变深导致深海碳酸盐沉积增加,这些因素综合作用的结果,使得冰期沉积的铁锰结壳Sr含量相对较高,间冰期沉积的铁锰结壳Sr含量相对较低.
The evolution curve of Sr content in ferromanganese crust samples with time has a similar trend with the δ18O curve of deep seawater, especially since 1Ma, both of them have a periodic change of about 100 ka, which is consistent with the change cycle of the orbital eccentricity. The results show that the Sr content of the Fe-Mn crust can trace the paleoclimatic change with the evolution of time since at least the late Quaternary.The factors affecting the Sr content in the Fe-Mn crust include the transition from the interglacial period to the glacial stage, the decrease of the sea level Causing carbonate dissolution in the offshore area. The decrease of seawater led to the increase of Sr in the ocean and the increase of biological productivity in the oceans. In the surface water of the shallow seawater, Sr migrated to the deep seawater with biological bodies and the depth of carbonate compensation in the ocean became deeper, As a result of the combination of these factors, the Sr content of the Fe-Mn crust deposited during the glacial period is relatively high, and the Sr content of the Fe-Mn crust deposited during the interglacial period is relatively low.