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阐述了青藏高原西昆仑山南侧甜水海湖岩芯沉积物中氧化铁的丰度、频率分布和富集系数的变化规律。其丰度值范围FeO0．39％-3.95％，平均值为1．25％；Fe2O30．44％－8．09％，平均值为2．60％；Fe2O3／FeO0．21－3．60，平均比值1．12。说明该彻岩芯沉积物中铁平均丰度值较低，但其变化幅度较宽且清楚，在一定程度上反映了古气候环境具有较大幅度的波动。变异系数值表明，该湖岩芯沉积物中FeO的离散程度较Fe2O3大。大约距今23万年来氧化铁的沉积地球化学特征可划分出7个环境演化阶段，并基本上可与深海氧同位索阶段对比。揭示了甜水海湖演化与青藏高原强烈隆升引起的气候环境改变的密切关系。在距今23一15万年，沉积以河流相或冲积、洪积相为主，沉积环境以氧化环境为主导，气候以温干型波动；在距今15－7．4万年，沉积以湖相为主，沉积环境以还原环境为主导，气候以温湿型为主；在距今74万年以来，湖盆沉积环境多样化，沉积物以湖相和近源冲积、洪积相交替出现。气候出现冷湿、冷干、温湿和温干多种波动模式。这些资料分析初步认为甜水海古湖大约形成于距今15万年，即青藏高原第三成湖期，这也与青藏高原在距今15万年左右的再次构造隆升有关。
The variation of iron oxide abundance, frequency distribution and enrichment coefficient in the sediments of the Shui Shuihai Lake in the south of the West Kunlun Mountains of Qinghai-Tibet Plateau are described. The abundance range of FeO0.39% -3.95%, with an average of 1.25%; Fe2O30.44% -8.09%, with an average of 2.60%; Fe2O3 / FeO0.21-3.60, the average Ratio of 1.12. This indicates that the average abundance of iron in the core sediments is lower, but its variation range is wide and clear, to a certain extent, it reflects that the paleoclimate environment has relatively large fluctuations. The coefficient of variation shows that the dispersion of FeO in the lake core sediments is larger than that of Fe2O3. About 230,000 years ago, the sedimentary geochemistry of iron oxide can be divided into seven stages of environmental evolution and can basically be compared with the deep-sea oxygen isotope stage. Reveals the close relationship between the evolution of sweet sea lake and climate change caused by the strong uplift of the Qinghai-Tibet Plateau. In the period of 23-150,000 years ago, the sedimentation mainly took the form of fluvial facies or alluvial deposits and alluvial deposits. The sedimentary environment was dominated by oxidative environment and the climate was warm and dry. In the period of 15-70,000 years ago, Lake facies dominated the sedimentary environment dominated by the reduction of the environment, the climate is mainly warm and humid; since the last 740,000 years, the lake sedimentary environment diversification of sediments to the alluviation of the lake and the near source, alternating with the alluvial appear. Climate appears cold and wet, cold dry, warm and humid and warm dry variety of fluctuations. These data suggest that Tianshui Lake formed approximately 150,000 years ago, that is, the third lake period of the Qinghai-Tibet Plateau, which is also related to the re-tectonic uplift of the Qinghai-Tibet Plateau about 150,000 years ago.