CAJ | 학술논문

鄂尔多斯盆地晚三叠世延长组沉积阶段经历了长.段沉积期、长_7段沉积期、长_(4+5)段沉积期3次主要湖侵期.运用钻井、测井等资料,综合分析了湖侵期储集砂体的沉积相类型、沉积演化规律,认为在湖盆西侧储集砂体主要为半深湖-深湖相浊积砂,东侧主要为深水型三角洲前缘水下分流河道砂.各湖侵期砂体展布特征具有差异性,长_9段砂体规模大,分布范围广,单层砂体厚;长_7段三角洲砂体规模较小,浊积砂体发育,局部地区具有叠合连片特征;长_(4+5)段盆地东北三角洲砂体延伸较远,横向连片性好,三角洲前缘水下分流河道砂体单层厚度薄,纵向多层叠加.研究还表明,湖侵期发育优质烃源岩,砂体具有较好的储集空间,生储配置关系好,易形成原生油藏,是下一步勘探的目标领域.
악이다사분지만삼첩세연장조침적계단경력료장.단침적기、장_7단침적기、장_(4+5)단침적기3차주요호침기.운용찬정、측정등자료,종합분석료호침기저집사체적침적상류형、침적연화규률,인위재호분서측저집사체주요위반심호-심호상탁적사,동측주요위심수형삼각주전연수하분류하도사.각호침기사체전포특정구유차이성,장_9단사체규모대,분포범위엄,단층사체후;장_7단삼각주사체규모교소,탁적사체발육,국부지구구유첩합련편특정;장_(4+5)단분지동북삼각주사체연신교원,횡향련편성호,삼각주전연수하분류하도사체단층후도박,종향다층첩가.연구환표명,호침기발육우질경원암,사체구유교호적저집공간,생저배치관계호,역형성원생유장,시하일보감탐적목표영역.
The Late Triassic Yanchang Formation in the Ordos Basin experienced three transgression periods of Chang 9, Chang 7 and Chang 4+5. Based on the drilling and logging data, the types of sedimentary facies and the evolvement of sediments are analyzed in the transgression periods. It is concluded that the reservoir sandstones are mainly semi-deep to deep lacustrine turbidites in the west of the lake basin, and are deep-water delta front distributary channel sands in the east. Distribution characteristics of sandstones are distinct in every transgression period. In particular, the Chang 9 sandstones are wide, intensive, and thick in monolayer;the Chang 7 sandstones are small, with turbidite sandstones developed, and stacked and connected locally;the Chang 4+5 sandstones in the northeastern delta of the basin are far extended, with good horizontal connection, thin monolayer of deep-water delta front distributary channel sands, and multiplayer superimposition vertically. The study also shows that in the transgression periods, good source rocks were developed, sandstones had good reservoir space, and the source, reservoir and seal rocks had good relationships, prone to form primary hydrocarbon reservoirs, and they are targets for exploration.