Late Holocene sedimentary records along the abandoned channel areas of the Yellow River and their response to flood hazards

This paper is the result of hydrogeological survey engineering.

Objective Late Holocene sedimentary records along the abandoned channel areas contain lots of paleoflood information in the lower Yellow River, which can help to extend extreme flood records, and are of great value in understanding flood hazard patterns.

Methods This paper selects Longwangmiao (LWM) profile (located in Daming County), Hebei Province, as the typical paleoflood section in the lower Yellow River. Luminescence dating, radiocarbon dating, gransize, and geochemistry analyses are combined with a synthesis of historical flood records and regional previous works.

Results The study concluded that: (1) Different facies in LWM profile, including paleosols, lacustrine deposits, overbank deposits, and slackwater deposits, have some close relationships with the others. (2) Four major flood deposits during the late Holocene are corresponding to four abnormal flood events in Zhou Dynasty, Western Han Dynasty, Northern Song Dynasty, and Ming Dynasty in this area. (3) Human activities have a profound impact on flood scale and frequency in the lower Yellow River, from seasonal floods to extreme floods.

Conclusions The study identified the characteristics of different sedimentary facies on lithology and environmental proxies, and explored the influence of human activities on floods. It provides a reference for paleoflood research along the abandoned channels in the lower Yellow River, and helps to further understand the processes and evolutionary mechanisms of flood hazards in the Yellow River.