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青藏高原东北边缘的贵德盆地发育巨厚的新生代地层,其中含较丰富的哺乳动物化石,在青藏高原北部很具有代表性.较精确地确定其地层年代对我国北方尤其西部哺乳动物演化进程和生态环境变化的研究,以及对高原隆升过程的研究具有重要的科学意义.古地磁测年表明含化石层位的贺尔加剖面年龄约为6.5-3.1 MaBP,第一、二和三化石层的年代分别约为5.25,5.1和4.4 MaBP.较精确地测定了贵德羚羊和中国互棱齿象的生存时代,它们分别出现于距今5.25和4.4 Ma.它们的演化与岩性和沉积速率变化共同指示青藏高原东北部此时处于强烈隆升的开始阶段,高原东部及其邻近山地的高度可能还不足以明显阻碍高原南北动物的交往.
The Youde basin, on the northeastern margin of the Qinghai-Tibet Plateau, is characterized by thick Cenozoic strata, including abundant mammalian fossils, which are representative of the northern part of the Qinghai-Tibet Plateau, and more accurately determine the evolutionary process of mammalian mammals in northern China, especially in western China And the study of the changes of the ecological environment and the research on the uplift of the plateau have important scientific significance.Paleomagnetic dating shows that the age of the Holga section with fossil beds is about 6.5-3.1 MaBP, and the first, second and third fossils The ages of the layers are about 5.25, 5.1 and 4.4 MaBP, respectively. The survival ages of the Endecidia antelope and the China’s geochelone are measured more accurately at 5.25 and 4.4 Ma, respectively. Their evolution and lithology and sedimentation The rate change indicates that the northeastern part of the Qinghai-Tibet Plateau is in the beginning of the intense uplift at this time. The height of the eastern plateau and its adjacent mountains may not be enough to significantly hinder the interaction of north and south plateau animals.