The following three maps on the formation of the North China plain are given by Ting Su (Bull. Inst. Ethnology, Academia Sinica 20, 1965, pp. 60-62). Their construction is not based on geological data, but by applying an estimated average cumulation of the Yellow River alluvium for the last 10,000 years, and by collaborating with known distribution of archaeological findings for the Yangshao culture (c. 5000-3000 BC ), Longshan culture (c. 3000-2000 BC ), and others.