摘要
东海中南部海底分布着广泛的脊槽状地形引起了人们广泛关注 ,有关文献称之谓全新世海进期的潮流沙脊 ;但对于沙脊的内部结构及其沉积环境序列、沙脊的活动性等问题 ,尚无明确结论。根据地震剖面和钻孔柱状样资料 ,对沙脊体的地层结构、沉积环境和沉积时代进行了研究 ,认为海底沙脊群属于海退期三角洲沉积体系 ,目前已被冰后期海进形成的已改造的陆架席状砂所覆盖 。
In the south of the East China Sea,are widely distributed ridge-trough landforms,which have attracted great attention,and in some documents,they are called Holocene transgressive tidal ridges,but the inner structure,sedimentary succession and movements of the ridges are not yet established.Studies on stratigraphic structures,sedimentary environment and sedimentation history of submarine dune ridges in the East China Sea have indicated the following results. (1) Inner structure and sedimentary succession of the dune ridges are typical of regressive delta on the basis of shallow stratigraphic profile and drilling. (2) Micro-paleontologic and sporopollen data from layerset Ⅱ of the seafloor dune are similar to those of deltaic succession in sedimentary environment. (3) Inner structure of the dune ridges is not consistent with structure and environmental characteristics of tidal dunes.Ridge bodies are not located at the same tidal erosion level.Each body cannot be an independent sedimentary trap and it becomes one successive system together with the underlying strata,surrounding strata and trough strata,and thus cannot be called tidal dunes. (4) After the formation of the submarine dunes,the surficial layers were once reworked by marine dynamic processes,but there are no evidences for their migration and movement.
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
2002年第1期9-14,共6页
Marine Geology & Quaternary Geology
关键词
沙脊
反射层组结构
沉积环境
东海
海底
dune ridge
structure of reflective layer set
sedimentary environment
the East China Sea
