在史前地质时期,据说华北大平原是一个海湾,山东地垒地带是海湾中的岛屿,后来黄河、海河、淮河等河流的冲积扇逐渐连成一片,形成了华北大平原。北宋时期科学家沈括在他著的《梦溪笔谈》一书中曾提出:“予奉使河北,遵太行山西北,山崖之间,往往衔螺蚌壳及石子如鸟卵者,横亘石壁如带,此乃昔 In the prehistoric geologic period, it is said that the Great Plains of North China is a gulf. The basement of Shandong Province is an island in the Gulf. Later alluvial fans of the rivers such as the Yellow River, the Hai River and the Huaihe River gradually became one and formed the Great Plains of North China. Northern Song Dynasty scientist Shen Kuo in his “Meng Xi Bi Tan,” a book was put forward: "To serve Hebei, compliance Taihangshan northwest, between the cliffs, often clam shells and gravel birds such as birds, It is past