海月构造带东三段滩坝砂分布及成藏主控因素分析

Beach bar sand distribution and main controlling factors of hydrocarbon accumulation of Ed_3 in Haiyue structure belt

辽河滩海地区海月构造带东三段沉积期,三角洲前缘砂体受湖岸流和波浪的改造,形成了一系列滩坝砂沉积,细分为滩砂和坝砂,水动力强则形成坝砂,水动力弱则形成滩砂;滩坝砂平行于湖岸线呈带状分布,易于形成岩性圈闭。滩坝砂受砂体发育规模、储层物性、断裂输导体系及封堵性等多种因素控制,在滩坝砂较为发育的东三下段,靠近海南断层、盖州滩断层且封堵条件优越的滩坝砂最易于成藏。

During the sedimentary period of Ed3 in Haiyue structure belt in Liaohe tidal area,a series of beach bar sand deposits were formed by the transformation of lakeshore flow and wave in the delta leading edge sand body,which were subdivided into beach sand and dam sand.The beach bar sand is distributed in a strip parallel to the shoreline of the lake,which is easy to form lithologic traps.While the beach bar sand is controlled by many factors,such as the development scale of sand body,reservoir physical properties,fault drainage system and sealing property,etc.In the lower Ed3 where the beach bar sand is relatively developed,the beach bar sand close to Hainan fault and Gezhou beach fault with superior sealing conditions is most likely to form reservoirs.