Geomorphological and Environmental Context of the Dinggong Site in Shandong Province, China

ZHENG Wenhao

Based on geoarchaeological research conducted at the Dinggong site on the east bank of the Xiaofu River in Shandong Province, China, the surrounding region experienced sequential loess and lacustrine-palustrine deposition from the Late Pleistocene to the Early Holocene. In the Early Holocene, the depositional environment transitioned to a fluvial facies, marked by the rapid development of alluvial fans. During the Middle Holocene, a river channel developed at the site's location, which subsequently silted up to form a paleochannel prior to the Longshan Culture period (4.4–3.8 ka BP). Flanking this paleochannel is an alluvial plain formed through the aggradation of the alluvial fan. During the Middle Holocene, the aggradation rate of this plain decreased significantly, accompanied by a reduction in overbank flooding. The geomorphic foundation of the Dinggong site rests on this relatively elevated paleochannel upon the alluvial fan. This higher topography, coupled with a decelerated rate of flood-induced aggradation during the Late Holocene, significantly mitigated the risk of inundation. Furthermore, micromorphological analysis of the deposits within the site's moat indicates that during its initial construction phase, the moat was likely interconnected with surrounding river channels, potentially serving water management functions related to both water supply and drainage. Borehole sedimentary records reveal the episodic development of small lakes on the surrounding floodplain during the Middle and Late Holocene. These local water bodies would have provided favourable conditions for rice cultivation and the exploitation of aquatic animal resources by the early inhabitants of Dinggong.