摘要
海滩层理由冲、回流塑造的向海倾前滨楔状交错层理和冲越流形成的向陆倾后滨斜层理组成,二者构成假背斜构造。近年在烟台—莱州岸段海滩上开挖了10个垂岸探槽,揭示出这里海滩以向陆倾后滨层理为主,并且被暴风浪侵蚀面所斜切,该面向海的前滨层理只留下几十厘米的薄层,说明近几十年海岸持续遭受侵蚀,海滩的前滨层理被多次暴风浪切割掉;按暴风浪期后滨层理层系特征分析,海岸蚀退率为1～1.5m/a,与其他方法得到的结论相仿。个别探槽亦见前滨层理为主,反映出局部淤岸环境。由此说明,海滩层理的组构特征可以标志海岸的淤、蚀动态。
Beach stratification usually consists of two parts, i.e. the seaward-dipping beddings on the foreshore side and the landward-dipping beddings on the backshore side. Through the study of 10 trenches perpendicular to the shoreline in Yantai and Laizhou, it is found that most of the beach strati- fication in the trenches is dipping landward with an inclined erosion surface on the top. And the seaward-dipping bedding is only a few dozen centimeters thick due to the erosion of storms in the past decades. In some trenches, the sequence is dominated by seaward-dipping beddings, indicating a silting environment. In conclusion, the characteristics of beach stratification could be used as a dynamic indicator of beach evolution.
出处
《海洋地质前沿》
北大核心
2011年第9期1-5,31,共6页
Marine Geology Frontiers
基金
山东省砂质海岸生境养护和修复技术研究项目(200905008-4)
关键词
海岸侵蚀
海滩层理
探槽照片
beach erosion
beach stratification
trench photo
