摘要:
晚更新世以来,中国近海北部陆架近岸地区至少发生了三次海侵并保留三期海相地层.在研究了数千千米的浅地层剖面仪测量资料及大量钻孔资料后,笔者发现最后冰期最盛时期陆架出露,海相地层并非简单地、原封不动地被保留下来.在强大的风力作用下,除进行正常的风成沉积以外,还产生了沉积分异作用,出现风暴沉积及其衍生沉积,裸露的陆架至少部分地改变了原来的沉积结构,形成了新的沉积类型,构成复杂的混杂堆积区和黄土堆积区.这样,原先的海相地层被破坏,或者部分被保留下来,即陆架上海相地层发生了解体.
Abstract:
There were at least three transgressions and three corresponding marine strata were left during Late Pleistocene in the shelf region of nearshore seas of China. In the regression during the last ice-age, the main feature of sedimentary environment in continental shelf region of nearshore seas of China were cold and dry. Wind-action was a major exogenetic force not only on land but also on the shelf region. The shelf area is partly desertized and desert deposits and their derivative sediments(loess deposits) were held. Based on the records of shallow layer profiler with total length of several thousand kilometres, it is found out that marine strata since Late Pleistocene were not preserved without disturbation. Under the intensive wind effect, the original sediment structure on the exposed shelf changed partly and formed new sedimentary type. So the disintegration of integrated marine stratum occurred in the shelf region of nearshore seas of China.
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