摘要
渤海湾西岸年轻贝壳堤的横截面呈上凸形态,堤的底板向海倾斜。年轻贝壳堤可分为底部-下部(前缘基足)、中部和上部三部分。底部-下部为形成于水下的(潮间带至潮下带上部)贝屑质砂坝。中部为障壁岛,岛后为泻湖环境;当岛后泥质充填迅速时,障壁岛可转化为沿岸堤。上部为风成沙丘。水下砂坝→障壁岛→沿岸堤→风成沙丘反映了贝壳堤多成因的、复杂的形成过程。障壁岛-泻湖体系是渤海湾西岸沿海平原形成的重要因素。
The transverse section of the younger cheniers (shell banks) on the west coast of Bohai Bay shows a convex morphology with its base tilting seawards. It consists of three parts: the basal-lower part, the middle part and the upper part. The basal-lower part, i. e. the buried front foot, is composed of water-laid shelly fragments mixed and/or weakly interbedded with mud. This is firstly piled up on the lower portion of the intertidal zone to the upper portion of the subtidal zone to form a subaqueous shelly shoals/bars/mounds. The middle part is barrier island and lagoon, including intertidal flat and middle and/or lower marsh environments, exists behind it. Occasionally , if mud accumulation occurring in the lagoonal area is quick enough, then the barrier island will be transformed into beach ridge. The upper part is windblown shelly dune, consisting of fine shelly fragments with several soil horizons. The subaqueous bars→barrier island→beach ridge→ windblown dune indicate that the younger cheniers experience polygenetic processes, which are a major factor of the coastal plain development.
出处
《地质论评》
CAS
CSCD
北大核心
2000年第3期276-287,共12页
Geological Review
基金
国家自然科学基金 (编号49672139)
中国-希腊政府间科技合作项目 (编号98015)的成果
关键词
贝壳堤
多成因过程
渤海湾西岸
形态
结构
subaqueous bar
barrier-island system
cheniers
polygenetic processes
the West Coast of Bohai Bay
