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首次在西宁盆地谢家剖面车头沟组底部发现原始埋藏的钙质木化石,不仅填补了植物大化石缺失的历史,同时对研究青藏高原东北部的植物生态环境演化和构造运动具有重要意义。通过对木化石埋藏特征、层位地层岩性和沉积环境的综合分析,认为其为近水河岸生长的成年乔木化石,株距3～8m不等,形成具有一定空间结构的植物群落,后期由于附近山地的隆起和该区气候向干旱化发展,植物遭受掩埋后经过石膏的交代作用进而形成硫酸钙质化石,说明该地区气候从中新世早中期开始恶化加剧。
For the first time, the originally buried calcareous fossils found at the bottom of the Chengtou Formation of the Xiejia Section in the Xining Basin, not only filled in the history of the fossil ablation of plants, but also played an important role in studying the evolution of plant ecology and tectonic movement in the northeastern Qinghai-Xizang Plateau. Based on the comprehensive analysis of the burial characteristics of wood fossils, lithology and depositional environment of stratigraphy, it is considered that adult arborous fossils are adult tree fossils grown near the banks of the river. The plant spacing varies from 3 to 8m, forming a plant community with certain spatial structure. In the later period, The uplift of the mountain and the development of arid climate in this area, the burial of plants after gypsum replacement and the formation of calcium sulphate fossils, indicate that the climate in this area has worsened since mid-early Miocene.