摘要：

主要通过岩心观察、粒度分析、参数计算、录测井分析等手段，充分吸收国内外河流研究成果，结合研究区区域地质背景，揭示垦东凸起北坡馆上段沉积相模式。得到以下认识：研究区馆上段地层为河流相沉积，从沉积物特征和平面形态角度可以将研究区馆上段河流沉积理解为介于辫状河及曲流河之间的过渡河型。其平均河道弯曲度大于1.7，垂向层序表现为泥多砂少，具有曲流河的特征；但沉积层序顶部常直接覆盖河漫/洪泛平原沉积，特别是河道内砂坝发育造成河道分汊河，砂坝沉积物粒度特征反映受洪水控制的震荡性特点而与曲流河有重要差别。本文借用在水利学界和地貌学界广为使用的分汊河概念建立了研究区馆上段沉积相模式，包括河床、堤岸、河漫/洪泛平原、废弃河道等4个亚相，组成下粗上细的正旋回。其中，河道砂坝是其主要砂体，顶部常被洪泛平原直接覆盖；决口扇是仅次于河道砂坝的第二大砂体。

Abstract:

The sedimentary model of the Upper Member of Guantao Formation on the northern slope of Kengdong uplift in Bohai Bay Basin was established by analyses of core observation, granularity data, parameter calculation, drilling and logging data, combining with the domestic foreign river research result. The investigation indicated that the Upper Member of Guantao Formation in the study area was fluvial deposition, and it could be determined as the transitional fluvial type between braided fluvial and meandering fluvial according to the sediment characteristics and the planar distribution. The average curvature of the channel is more than 1.7, and the vertical sequence is characterized by meandering fluvial deposits with higher content of mudstone and lower content of sandstone.The top of the sequence usually directly overlied the flood plain deposits, especially the channel distributed fluvial was formed due to the development of the sandbar in the interior of the channel. The granularity characteristic of the sandbar sediments showed great difference from the meandering fluvial facies, that is, it is controlled by flood. In this paper, the sedimentary model for the Upper Member of Guantao Formation was established in terms of the anabranched river concept which is used widely in hydraulics and topography. The subfaices includes fluvial bed, bank, floodplain, abandoned channel which constituted a fining upward positive cycle. The channel sandbar is the main sandbody and is usually directly overlied by floodplain deposits. The crevasee fan sandbodies are seconly favorable to the channel sandbar.