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The Shandong peninsula along the coastal Bohai Sea in China is mainly a vast alluvial plain formed by the Yellow River, and it is an ideal area to study the evolution oflandform in a river-sea interaction area in which chronology is the key. However, the detailed OSL chronology of cores in this area is lacking. In this study 22 OSL samples have been collected from the upper 40 meters of DZK01 core (100m in depth) to establish a chronology using quartz Single Aliquot Regeneration (SAR) + Standard Growth Curve (SGC) methods. Preheat plateau test and laboratory dose recovery test showed that the SAR protocol was applicable to these samples whose recuperation was negligible. Three radiocarbon samples were also dated for cross-checking. Sedimentation rate was calculated based on the dating results. The paper then discussed sedimentology and geomorphic evolution of the lower Yellow River since the late Pleistocene. [ABSTRACT FROM AUTHOR]

Two layers of lacustrine deposits within Holocene exist widely in the North China Plain, representing two dramatic environmental transition events, which has significant implications for both Yellow River migration and neolithic human activity in the flooding plain. However, the ages, distribution, and environmental significance of these two layers are still unclear. In particular, previous chronological data are mostly by a few sparse radiocarbon ages, and systematic chronology investigation and luminescence ages are very limited. In this study, three boreholes were obtained from Anyang (core HX05), Puyang (core NC02), and Jinan (core ZK1), respectively. Core NC02 is about 60 km away from Core HX05 to the south, and is about 234 km away from core ZK1 to the east. The two layers of lacustrine deposits are observed in all three cores and in similar depths. Quartz optically stimulated luminescence (OSL) and radiocarbon dating are applied to determine the age of the two lacustrine sediment layers. The dating results indicate that the age of the lower lacustrine layer is about 10 ka, and that the upper lacustrine layer is about 3 ka. The implications of the dating results for paleoenvironmental change, Yellow River migration, and neolithic human activity in the flooding plain will be discussed. [ABSTRACT FROM AUTHOR]

The Yellow River is one of the largest rivers in the planet. Some part of its channel in its low reaches of the flooding plain is now more than 10 meters higher than the surrounding land, imposing great threat for human life. It is critical to decipher the sedimentary and channel migrating history to sort out the issue. Core JNZK1 was obtained from Jinan in Shandong Province in the Yellow River Plain in China with a depth of 740 m, in order to reconstruct the history of the river. The OSL ages are very limited in these area, and there is by far no systematic OSL chronology for drilling cores. In these study, OSL samples were collected from the top 40 m of the core in order to establish detailed chronology. OSL ages showed that a sample at the depth 15.6 m had an age of c. 11 ka, indicating the bottom of the Holocene sediment. OSL age then soon reached saturation at a depth of c. 22 m, suggesting a hiatus occurred in between possibly due to the erosion during last glacial. Radiocarbon samples were also collected where available. The current study tried to provide a preliminary chronological framework for further sedimentary and paleoenvironmental studies in the flooding plain. [ABSTRACT FROM AUTHOR]