关于全球气候变化过程的研究一直是国内外关注的焦点，而将 GR 曲线应用于重建古环境、古气候方面的工作目前还处于尝试性阶段。本文在研究七23井 GR 曲线的基础上，利用水体盐度、古生物化石资料加以验证，发现 GR 曲线可以敏感地反映古气候、沉积环境的变迁。并据此完整恢复了研究区干旱气候→暖湿气候→干旱气候的4次波动，扇三角洲相与滨浅湖相的交替沉积，水体在湖盆扩张与收缩过程中浅→深→浅的变化。且在 GR 值下降→气候变干→水体变浅的普遍规律下，总结出波频高低和波幅大小的一系列组合可以较为详尽的反映沉积环境信息。同时 GR 曲线的突变有记录短时间内沉积环境及气候突变事件的能力，由此可提取出研究区与青藏高原隆升有关的古地理信息。故 GR 曲线能够成为恢复古环境、古气候的有用参考指标。%The process of global climate change is always the focus of academic circles in China and abroad, but the application of GR curve in the reconstruction of paleoclimate and paleoenvironment is still at the ex-perimental stage.Through the research of GR curve of shaft Qi-23 and based on the verification by utilizing salinity of water and data of paleontological fossils,this paper discovered that GR curve could sensitively re-flect the changes of paleoclimate and paleoenvironment.Based on the findings,the author completely recon-structed the 4 climatic fluctuation (arid climate→warm-humid climate→arid climate),alternative deposition of fan delta facies and coastal shallow lake facies,as well as the changes of water body during the extension and shrinkage of lake basin (shallow → deep → shallow)in the study area.In light of the universal law of GR value decrease→ dryingclimate →shallowing of water body,the author concluded that the combinations of wave frequencies and amplitudes could reflect the sedimentary environment information in detail.Moreover, the abrupt changes of GR curve is capable of providing a record of the abrupt changes of sedimentary environ-ment and climate which occur within a short period,whereby paleogeographic information related to uplifts in the study area and Qinghai-Tibet Plateau can be extracted.Therefore GR curve can be used as useful refer-ence indexes in reconstruction of paleoenvironment and paleoclimate.
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