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根据区域调查和对南京江北剖面沉积物及埋藏古树和炭化木的年代测定，以及对孢粉、粒度、石英砂表面特征鉴定分析，发现本区存在晚北方期至亚北方气候期（８２００±１２６ａＢＰ、７８２２±２５０ａＢＰ～７６７０±１６０ａＢＰ、７５６２±９０ａＢＰ、４０８５±９５ａＢＰ～４０９０±１００ａＢＰ以及３７３０±９０ａＢＰ）具有洪积特征的天然剖面地层，该剖面位于长江北岸二级阶地上，其洪积层系由古洪水期长江摆动时沉积所致。剖面上部厚０．５３ｍ的灰黄色土层系在亚北方期大约３０００ａＢＰ～２８５０ａＢＰ的寒冷期中主要由风尘搬运堆积所致。
According to the regional survey and the dating of the sediments, burial ancient trees and carbonized wood in the Jiangbei section of Nanjing and identification of the surface features of sporopollen, grain size and quartz sand, it is found that the region exists from late Northern to late Northern climate (8200 ± 126aBP, 7822 ± 250aBP ~ 7670 ± 160aBP, 7562 ± 90aBP, 4085 ± 95aBP ~ 4090 ± 100aBP and 3730 ± 90aBP). This section is located on the second terrace of the north bank of the Yangtze River and its alluvial layer Sedimentation caused by the swinging of the Yangtze during the flood period. The yellowish-yellow soil layer with a thickness of 0.53m in the upper part of the profile was mainly caused by dust and dust accumulation in the cold period of about 3000a BP to 2850aBP in the sub-northern part of China.