Abstract: A sequence of Neocene gypsum-beating sandy and muddy strata has been recently found in the Xianlin University City, Nanjing, by drilling during urban stereo geological mapping in key areas of Nanjing. This sequence of strata may be correlated with sedimentary strata of the Yuhuatai Formation in Lingyan Mountain, Liuhe district, Nanjing. This discovery is of great significance in reunderstanding the structure of the loose cover above the bedrock surface of some similar downfaulted basins in the Nanjing area. In addition, the influence of its discovery on the environmental and engineering geology of the area is evaluation and the participation of groundwater in mineralization is also discussed.