辽东湾海岸地貌近代演化特征

RECENT EVOLUTIONARY CHARACTER OF COASTAL LANDFORM IN LIAODONG BAY

辽东湾海岸类型及其分布受区域地质构造控制。海岸类型可分为:港湾型基岩海岸、岛礁型基岩海岸、岬湾型沙质海岸、平原型淤泥质海岸等4类;潮间带地貌分为海滩、潮滩、岩滩3类;水下堆积地貌主要有水下三角洲及潮下浅滩。受河流输沙影响,淤积先从河口开始,然后向外围扩散。在湾顶部,地貌及内、外动力条件利于海岸淤涨,但受滨岸海洋水文条件制约,发展不均衡,可出现局部短时间的侵蚀后退现象。海岸工程可控制海岸的演化过程,滩涂地带引种植物可促进海岸持续淤涨。

The coastal types and their distribution of Liaodong Bay are controlled byregional tectonic. There are four types of coast:indented-type solidrock coast, reefcoral-type solidrock coast, fjord-type sand coast, plain-type puddly coast. Thelandform of intertidal zone is divided into three types:beach, tidal beach, rock beach.The landform of subaqueous sediments mainly have subaqueous delta and subtidalshoal.Influenced by transport of river, alluviation begins from river mouth, thenspreads outward.At the top of the bay,the canditions of internal force and exogeneticforce are favourable to coastal alluviation. But they are restricted by coastal marinehydrogeological canditions; the development is disequal; the phenomenon of erosionrecessin partially appears at short-term.Coastal engineering can command the evolutionprocess, planting on beach zone can accelerate the continue of coastal alluviation.