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青藏高原甜水海湖钻孔岩心是一套连续和完整的第四纪沉积层序，通过对沉积地球化学信息的综合分析，初步建立了２３万年来的气候曲线。揭示了几次较大的降温信息，约１５万年以前，年平均气温为－１．６３℃，气候温干，沉积以氧化环境为主导；在６阶段后期，呈现气候波动频繁，沉积环境不稳定；进入５阶段，即进入末次间冰期，气温下降，年平均气温较６阶段降低２．８３℃；约７．４万年以来，即进入末次冰期，４阶段气温较５ａ亚段降低０．７３℃；约２．５万年以来，即进入末次冰期最盛期，２ｂ亚段气温较３ａ亚段降低２．２１℃。２３万年以来甜水海湖岩心的沉积记录研究所划分的７个沉积阶段基本上可与深海氧同位素标准曲线对比。初步认为甜水海古湖大约形成于１５万年以来，即青藏高原第三成湖期，同时与青藏高原１５万年构造运动的再次隆升有关。
The core of Tianshui Lake in the Qinghai-Tibet Plateau is a set of continuous and complete Quaternary sedimentary sequence. Based on the comprehensive analysis of sedimentary geochemical information, the climate curve for 230,000 years has been initially established. Revealed a few large cooling information about 150,000 years ago, the annual average temperature of -1.63 ℃, the climate is warm and dry, the deposition is dominated by the oxidation environment; in the late stage of 6, showing frequent fluctuations in the climate, sedimentary environment is not Entered the last stage of interglacial period, the temperature dropped, the annual average temperature decreased by 2.83 ℃ compared with the 6th stage; about 74,000 years, that is, it entered the last glacial stage, and the temperature in the 4th stage decreased by 0 than that in the 5th stage. 73 ℃; about 25000 years, that is, into the peak of the last ice age, 2b sub-paragraph temperatures than the 3a sub-paragraph 2.21 ℃. For the past 230,000 years, the sedimentary records of the Tianshui Lake core sediments recorded seven sedimentary stages basically comparable with the deep sea oxygen isotope standard curve. It is preliminarily believed that the Shuihuhai Lake formed about 150,000 years ago, that is, the third lake period of the Qinghai-Tibet Plateau, and related to the re-uplift of the structural movement of 150,000 years on the Qinghai-Tibet Plateau.