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1976年和1977年夏天,在荷兰西南部东斯凯尔特河口附近对中湖差区浅滩和滩间水道沉积体进行了详细的调查。这次调查的目的是建立地貌随时间的变化情况和这些变化对保存下来的沉积层序发育的影响之间的关系。调查的区域划分成四个地带。每个地带都有其独特的沉积作用及其相应的底部形态:a)外部水道弯曲和边缘地带,在这一地带主要是一些涨潮方向控制的大型链状波痕和沙波;b)水道最深谷底线和内部弯曲地带,这一地带主要是落潮控制的大波痕;c)内部水道边缘带,这一地带的特征是存在天然堤坝。d)毗连浅滩区域,这一带一般是很平缓的,但也有一些块状分布的涨潮或落潮控制的大型波痕。每一地带保存下来的沉积构造的垂直层序或多或少是与各自地带中现存的占主导地位的底部形态相一致的。层序分析表明,外部水道边缘带中的净沉积与内部水道边缘地带相比较就少得多了,这意味着内部水道边缘地带的横向增生单元,在这种模型的浅滩和滩间水道沉积体的保存层序中是一个主要的特征,同时与外部边缘层序相比,内部边缘层序的沉积构造保存潜势就高得多了。结果,大波痕尽管是很大一部分调查区域中的主要底部形态,却较少能保存下来,在类似的古代层序中大波痕仅形成很小一部分层序。
In the summer of 1976 and in the summer of 1977, a detailed investigation was carried out of the sediments in the shallow and intertidal banks of the Central Lake in the vicinity of the Eastern Celtic Estuary in the southwestern part of the Netherlands. The purpose of this survey is to establish the relationship between changes in landscape over time and the impact of these changes on the preservation of the sedimentary sequence. The area surveyed is divided into four zones. Each zone has its own unique sedimentation and its corresponding bottom morphology: a) External watercourse curves and marginal zones, mainly in the area of large chain-like ripples and sand waves controlled by the direction of the tides; b) Bottom line and internal bending zone, which are mainly large waves of ebb control; c) internal watercourse margin zone, which is characterized by natural levees. d) Adjacent to the shoal zone, the zone is generally flat, but there are also large ripples of lumps or ebb-controlled patches. The vertical sequence of sedimentary structures preserved in each zone more or less coincides with the dominant dominant bottom morphology present in each zone. The sequence analysis shows that the net sedimentation in the outer waterway margin zone is much less compared with the inner waterway margin zone, which means that the lateral proliferation units in the marginal zone of the internal waterway, in which the shallow and inland waterway sediments Is a major feature in the preservation sequence, and the preservation potential of the sedimentary structure of the internal margin sequences is much higher than that of the outer margin sequences. As a result, large beacons, although major bottoms in a large part of the surveyed area, are less preserved and large ripples form only a small part of the sequence in similar ancient sequences.