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泥河湾盆地井儿洼剖面古地磁测年结果全部为正向极性 ,剖面顶面下 3.0 8m处白垩质粘土层铀系不平衡法测年结果为 (50 6 0 0± 6 70 0 )aBP ,据此确定其磁性地层学时代为布容正向极性时 .剖面底部未出露B/M界限 ,说明地层时代晚于 78万aBP .依据磁性地层学特征 ,井儿洼剖面可与虎头梁剖面对比 ,并能与红崖南沟、大道坡、郝家台等剖面的上部或顶部对比 ,属泥河湾组Ⅲ段 .井儿洼、虎头梁剖面下部的石膏沉积晚于红崖、铺路等剖面下部的石膏沉积 ,它们分属不同的石膏沉积旋回 .井儿洼剖面出露的湖相地层记录了古湖的消亡过程 ,是研究泥河湾古湖晚期历史的理想场所
The paleomagnetic results of the Jing’erwa profile in the Nihewan Basin are all of positive polarity. The results of the Uranium Series Imbalance at Cretaceous clay layer 3.08m at the top of the profile are (50 6 0 0 ± 6 70 0) aBP, it is determined that the magnetic stratigraphic time is the positive polarity of cloth, and the B / M boundary is not exposed at the bottom of the profile, indicating that the stratigraphic age is later than 780,000 a BP. According to the characteristics of magnetic stratigraphy, Compared with the top or top of the section of the Ngougou, Dapopo, Haojiatai, etc., it belongs to the section III of the Nihengtou Formation.Gypsum deposition in the lower part of the Jingliao and Hutotai sections later than that of the Red Cliff , Paving and other sections of the lower part of the gypsum deposition, which belong to different gypsum sedimentary cycle.Jianer depression profile exposed lake facies recorded the demise of the ancient lake process, is to study the late ancient Nihewanhewan ideal place