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具有适量沉积物的窄基岩形成的瓜迪亚纳 (伊伯利亚半岛西南 ) 河口晚第四纪沉积构成的研究应用了高分辨率地震地层学的概念。地震相和瓜迪亚纳河谷的地层剖面之间的相互关系使得河谷充填的精细层序地层解释成为可能。因为增加的沉积物旁通到现今的中、远陆架, 所以在距今最近的冰川低水位期间, 瓜迪亚纳是河流沉积物堆积厚度不大的地表河谷。到冰川期后的海侵末期, 该地表河谷转变为河口, 而且沉积物开始优先在构造洼地内沉积, 进而潮汐流受到基岩隆起的限制而增加了在河口较高部位的砂质沉积。波浪作用的影响减小并且被限制在较低的河口体系。在这里, 河谷的狭窄地形导致了在全新世的高水位期增加的沉积物外排到大陆架。河口充填较低部位的沉积物是由 4个第 5沉积层序组成的, 由海退沉积物高水位体系域 (HST) 组成。不同的地层表面记录了距今最近的最大冰川期, 同时, 它也是层序界面和冲沟侵蚀面。潮汐海浸表面呈现出外河口区较强的侵蚀和河道地层特征。向陆海侵沉积和下超高水位期沉积之间的地层结构的变化可确定出最大水淹面。海侵体系域 (TST) 和海退体系域(HST) 是在后冰川期的海侵末期和其后的高水位期沉积而形成的。
The study of the Late Quaternary sediments of the Guadiana (estuarine southwest) estuary formed by a narrow bedrock of moderate sediments applied the concept of high-resolution seismic stratigraphy. The correlation between the seismic facies and the stratigraphic profile of the Guadiana Valley makes it possible to interpret fine-sequence stratigraphy in valley fill. Guadiana is a surface valley of small river sediment accumulation during the recent glacier low water level because of additional bypasses to the present mid-long shelf. At the end of the glacial-to-sea transgression, the surface valleys turned into estuaries and sediments began to deposit preferentially in the depressions. The tidal flow was then restricted by bedrock bumps and increased the sedimentation of the higher parts of the estuaries. The effect of wave action decreases and is limited to lower estuarine systems. Here, the narrow terrain of the valley led to the exodus of sediments to the continental shelf during the Holocene high water level. Sediments in the lower estuary filling area are composed of four fifth sedimentary sequences and consist of the highstand water system tract (HST) of the receding sediments. Different stratigraphic surfaces record the most recent glacial period to date, and at the same time it is also a sequence boundary and gully erosion surface. Tidal sea immersion surface presents a strong erosion of the estuarine zone and channel stratigraphic features. Changes to the stratigraphic structure between the inland and transgressive sediments and the deposition under the ultra-high water level can determine the maximum waterflooding surface. The transgressive system tract (TST) and retrogressive system tract (HST) are formed during the post-transgressive period of the post-glacial period and the subsequent high water level.