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对青藏高原北部柴达木盆地西北缘红三旱地区古近系高精度的磁性地层研究表明,下干柴沟组的磁极性带对应标准地磁极性年表C16n—C18极性时熏相应的磁性年代为大于40Ma至35.5Ma,其地质时代属于始新世早、中期;上干柴沟组的磁极性带对应C8.2n—C15极性时,相应的磁性年代为35.5～26.5Ma,地层的地质时代属于始新世晚期和渐新世早、中期。上、下干柴沟组的界线位于C16n顶部,其年代约为35.5Ma。上干柴沟组顶部的砂砾岩或砾岩层,以及沉积速率的大幅增加可能是该地区在27.9～26.5Ma期间规模隆升的结果。
The study on the high-resolution Paleogene strata in the Hong-Sanhan region on the northwestern margin of the Qaidam basin in the northern Qinghai-Xizang Plateau shows that the magnetic polarity of the Xiaganchaigou Formation corresponds to that of the standard geomagnetic polar chronology C16n-C18 The magnetic age is more than 40Ma to 35.5Ma, and the geologic age belongs to the early and middle Eocene. The magnetic polarity of the Shangganchaigou Formation corresponds to C8.2n-C15 polarity, and the corresponding magnetic age is 35.5-26.5Ma. The geologic age belongs to late Eocene and Oligocene early and middle period. The boundaries of the upper and lower Ganchaigou formations are at the top of C16n with a age of about 35.5Ma. The glutenite or conglomerate layers on the top of the Ganchaigou Formation and the substantial increase in sedimentation rate may be the result of the large uplift in the area from 27.9 to 26.5 Ma.