Abstract The Red River Delta (RRD), one of the two largest deltas in Vietnam, has been severely affected by natural hazards induced by global climate change. Understanding the Holocene paleoshoreline is crucial in developing adaptive planning in response to future shoreline changes based on past natural shoreline changes. This study presents new data pertaining to pollen, grain size, lithological characteristics, and 14C dating of six cores from the RRD. The purpose of this study was to determine the paleoenvironments and paleoshorelines of the RRD in the Holocene to provide information useful for modeling future changes, e.g., for calibration sea level in paleobathymetry and sea level change models; for making the necessary ecological and cultural adaption to survive. We identified 4 units and 10 sedimentary facies indicating periods of sedimentary evolution since late Pleistocene. The main indicators for paleoshoreline interpretation are true mangrove and backmangrove pollen. The inferred paleoshoreline changes and five paleogeographic maps for 10.5, 9.2, 7.8, 6.5, and 3.7 cal. kyr BP were constructed based on paleoshoreline indicators, and paleoenvironmental reconstructions from the dataset of our whole RRD study area.

中文翻译：

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越南红河三角洲全新世古海岸线变化

摘要 红河三角洲（RRD）是越南最大的两个三角洲之一，受到全球气候变化引发的自然灾害的严重影响。了解全新世古海岸线对于根据过去的自然海岸线变化制定适应性规划以应对未来海岸线变化至关重要。这项研究提供了有关 RRD 六个岩心的花粉、粒度、岩性特征和 14C 测年的新数据。本研究的目的是确定全新世 RRD 的古环境和古海岸线，为模拟未来变化提供有用的信息，例如，用于校准古测深和海平面变化模型中的海平面；进行必要的生态和文化适应以生存。我们确定了 4 个单元和 10 个沉积相，表明自晚更新世以来的沉积演化时期。古海岸线解释的主要指标是真正的红树林和后红树林花粉。推断的古海岸线变化和 10.5、9.2、7.8、6.5 和 3.7 cal 的五张古地理图。kyr BP 是基于古海岸线指标和我们整个 RRD 研究区数据集的古环境重建构建的。