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中新世早期青藏高原腹地曾经发育了面积巨大的古大湖,此时恰逢青藏高原的快速隆升关键时期。为研究高原腹地在此期间环境的演化,对五道梁组中介形虫壳体的Mg/Ca和Sr/Ca的值进行了测试。通天河盆地五道梁组地层中的介形虫壳体的Mg/Ca和Sr/Ca数值的特征,结合剖面岩性特征,反映了23.8~21.8 Ma前该湖泊区域气候由湿润-干旱-暖湿的演化趋势。其气候的变化可能是此时期青藏高原从快速隆升到剥蚀夷平后高原北部构造隆升活动的结果。该研究为进一步了解青藏高原腹地的古环境探索了一条新的途径。
Early in the Miocene, the Great Paleo-lakes had been developed in the hinterland of the Qinghai-Tibet Plateau, which coincided with the crucial period of rapid uplift of the Qinghai-Tibet Plateau. In order to study the evolution of the environment in the plateau in the middle of the plateau, the values of Mg / Ca and Sr / Ca in the shell of Wudaoliang were tested. The characteristics of the Mg / Ca and Sr / Ca values of the ostracod shells in the Wudaoliang Formation strata in the Tongtianhe Basin, combined with the lithological characteristics of the profiles, reflect that before 23.8-21.8 Ma the climate in this lake region is changed from humid-arid-warm Wet evolution. The climate change may be the result of the tectonic uplift activities in the northern plateau since the Qinghai-Tibet Plateau rose rapidly from this period to denuded and leveled. This study explores a new way to further understand the paleoenvironment of the hinterland of the Qinghai-Tibet Plateau.