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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 research on the global climate change process has been the focus of attention both at home and abroad. However, the application of the GR curve to the reconstruction of paleoenvironment and paleoclimate is still at a tentative stage. Based on the study of the GR curve of Well Qi 23, this paper verifies the salinity and paleontology data of water bodies. It is found that the GR curve can reflect the changes of paleoclimate and sedimentary environment sensitively. And thus completely restored the four fluctuations of the arid climate → the warm and humid climate → the arid climate in the study area, the alternating sedimentation of the fan delta facies and the shallow lake facies, the shallow → deep → shallow changes of water bodies during the expansion and contraction of the lake basin . And under the general law of GR value descending, climate desiccation and water body shallowing, it is concluded that a series of combination of wave height and amplitude can reflect sedimentary environment information in detail. At the same time, the abrupt change of GR curve can record the sedimentary environment and abrupt events in a short period of time, so the paleogeographic information related to the uplift of the Qinghai-Xizang Plateau can be extracted. Therefore, the GR curve can be a useful reference index for restoration of paleoenvironment and paleoclimate.