The control of Pleistocene palaeogeography on the distribution of sandy patches in a silty Holocene lagoon(central Netherlands)

作     者：Ai-Ping Fan A.J.(Tom)van Loon Ren-Chao Yang Ai-Ping Fan;A.J.(Tom)van Loon;Ren-Chao Yang

作者机构：College of Earth Science and EngineeringShandong University of Science and TechnologyQingdaoChina Laboratory for Marine Mineral ResourcesQingdao National Laboratory for Marine Science and TechnologyQingdao 266071China 

出 版 物：《Journal of Palaeogeography》 (古地理学报（英文版）)

年 卷 期：2022年第11卷第4期

页      面：565-583页

核心收录：

学科分类：070905[理学-第四纪地质学] 070903[理学-古生物学与地层学(含：古人类学)] 0709[理学-地质学] 07[理学] 0708[理学-地球物理学] 

基　　金：supported by the China-ASEAN(Association of Southeast Asian Nations)Maritime Cooperation Fund Project(grant No.12120100500017001) the National Natural Science Foundation of China(grant No.41972146) 

主　　题：Lagoonal palaeogeography Netherlands Noordoostpolder Wave erosion Abrasion Holocene 

摘      要：The brackish lagoon in the central part of The Netherlands was closed by a dike in 1932 and gradually changed into a *** of this lake were reclaimed and the surficial sediments of one of the polders(Noordoostpolder),reclaimed in 1942,has been investigated in detail by mapping of the walls of some1500 km of drainage ditches approx.1.4 m *** appeared that the sediments consist of an uncommonly large amount of silt,to different degrees mixed with reworked peat that had developed during the Holocene *** sandy deposits occur locally,at places that are at first sight distributed in a haphazard *** various sandy patches have different characteristics(grain-size distribution,rounding of the grains,mineral composition).These sands cannot have been introduced from the sea,nor can they have been supplied by the rivers that discharged into the lagoon,so they must have a local *** is found that several types of Pleistocene sandy or diamictic deposits below the Holocene peat and lagoonal sediments had an irregular topography and became eroded during the Holocene by wave *** resulted in sandy deposits around these Pleistocene highs,which consisted of glacial tills(boulder clays),river dunes(formed by aeolian activity along rivers under dry permafrost conditions)and coversand ridges,formed by aeolian activity in a belt between the ice margin and the more distal loess *** finding implies that palaegeographical interpretations of local grain-size anomalies in a specific deposit should not only consider facies changes due to changes in the sediment supply,but should also consider local erosion leading to the exposure of previously deposited material with a divergent composition.