本区晚更新世晚期的前期和中期阶段以河流沉积为主,晚期阶段及早全新世早期湖相沉积逐渐占重要地位.晚更新世晚期海平面大幅度下降导致侵蚀基准面下降,河流下切,使晚更新世中期的海相地层遭受侵蚀,导致海产动物化石被搬运和再沉积.垦利组陆相地层中发现的有孔虫、双壳类等海相化石是由于海面变化引起的再沉积的产物. In the late Pleistocene, the river sediments dominated in the early and mid-late stages of the Late Pleistocene, and lacustrine sediments gradually dominated in the late stage and early Early Holocene.The sharp decline of sea level in the Late Pleistocene resulted in the decrease of erosion datum and river cutting The marine strata eroded in the mid-late Pleistocene, causing the fossils of marine animals to be transported and redeposited.The marine fossils such as foraminifera and bivalve found in the continental strata of Kenli Formation are re-deposited due to sea surface changes product.