【作者】 刘军锷；

【导师】 操应长； 邱桂强；

【作者基本信息】 中国石油大学 ， 地质工程， 2010， 硕士

【摘要】 民丰地区位于东营凹陷东北部,北部紧邻陈家庄凸起,东接青坨子凸起,沙三、沙四段沉积时期发育了巨厚的生油岩和丰富的储集砂体,具备优越的油气成藏条件,已成为东营凹陷油气勘探的储量接替阵地之一。综合利用钻井岩心、录井、测井、地震等资料,层序地层学、沉积学、石油地质学等理论和技术方法,对民丰洼陷沙三、沙四段沉积特征、储层特征及油气成藏条件等开展了系统性研究。民丰地区地层发育较全,对重点层系沙四下亚段、沙四上亚段和沙三中亚段进行了细分,其中沙四下和沙三中亚段分别划分为6个砂层组、沙四上亚段划分为4个砂层组。通过重矿物、特征元素分布、砂砾岩百分含量等资料的综合分析,沙三-沙四段沉积时期主要发育了北部、东部和东南部三个方向的物源体系。在物源体系控制下,研究区主要发育了近岸水下扇、扇三角洲、河流-三角洲、滑塌浊积岩及坡移浊积扇等沉积相类型。沙四段沉积时期以发育来自北部物源体系的近岸水下扇沉积为主,沙三中亚段和沙三上亚段沉积时期以发育来自东部和东南部物源体系的河流三角洲-滑塌浊积岩沉积为主,沙三下沉积时期属于北部和东部物源体系的过渡沉积时期。由于沙四下亚段的上部发育多套稳定分布的盐膏层,形成了盐上和盐下两套相对独立的含油气系统。其中盐下(即沙四下亚段)烃源岩是2007年发现的一套新的高成熟度优质烃源岩。沙四下亚段的油气为三期冲注,其主要储集类型是近岸水下扇,属于凝析油气藏,自生自储类型。扇中亚相是有效储层,储层具有低孔低渗、物性控藏的特点,成藏特点是扇根封堵、扇中富集、叠合连片。盐上(沙四上亚段-沙三中亚段)发育三套烃源岩,分析认为沙三中亚段为非主力烃源岩,油气主要源自沙三下和沙四上亚段烃源岩,分为它源和自源两种成藏模式。沙三-沙四上亚段储层目前已基本进入了中成岩A1亚期阶段,储层的储集空间以次生溶解孔隙为主。沙四上亚段以砂砾岩扇体岩性油气藏为主,沙三中亚段以浊积岩岩性油气藏为主。油气的分布与富集主要受控于宏观构造背景、沉积相带、储层厚度、封堵性、断层、地层压力等多种因素等。提出了扇根侧向封堵的观点,实现了近岸水下扇由构造向岩性勘探思路的转变。通过以上综合分析,提出有利勘探目标21个,目前已部署12个,上报控制石油地质储量4884万吨,预测石油地质储量1011万吨。更多还原

【Abstract】 Minfeng area is located in northeast Dongying depression. Chenjiazhuang uplift is adjacent to its north, and Qingtuozi uplift is adjacent to its east. Thick source rocks developed during Es3 and Es4 depositional period, and abundant reservoir sand developed surrounding Minfeng sag, which provided advantageous reservoir-forming conditions, and has become the next importantly reserve replacement area of exploration. Using core drilling, logging, and seismic data, and sequence stratigraphy, sedimentology, petroleum geology theories and technologies, the sedimentary characteristics, reservoir characteristics, and reservoir-forming conditions in Es3 and Es4 Formation of Minfeng Sag is systematically studied.The formations are fully developed in Minfeng area, and the formations Es4x, Es4s and Es3z are delicately divided, additionally, the formation Es4-x and Es3z-x are respectively divided into 6 sand sets and the formation Es4x is divided into 4 sand sets.The comprehensive analysis of heavy minerals, glutenite content and features element distribution indicated that northern, eastern and southeastern source systems developed during Es3 and Es4 depositional period. Under the control of the three source systems, nearshore subaqueous fans, fan deltas, river-deltas, deep-water slope turbidite fans, landsliding turbidites and slope turbidite fans developed in the study area. During the Es4 depositional period, nearshore subaqueous fans from the north source system developed; during Es3z-x depositional period, river deltas and fluxoturbidites from eastern and southeastern source system developed; lower Es3 depositional period was the stage that source system changeed from north to east.Because of the steady distribution of several salt-gypseous horizons above Es4x layer, two hydrocarbon systems that are upper salt bled and lower salt bled are formed. The source rock of the lower salt bled hydrocarbon is a suite of well high maturity source rock, which was new found in 2007. The gas and petroleum of reservoirs in Es4x layer are injected in three times, and reservoirs are nearshore subaqueous fans and condensate reservoir, they can be recognized as both reservoirs and source rocks. The available reservoirs are middle fan subfacies, which have traits of lower porosity, lower permeability, and the forming of which is controlled by physical characters. The reservoirs are enrich in middle fan subfacies, overlapped, continuous and sealed by root fan subfacies.There are three suites of source rocks for the upper salt bled (Es4 and Es3z-x), the Es3z one is not the main source rock, and the Es4s and Es3x are main source rocks. The reservoirs accumulation type are divided into other resource type and self resource type.The lithology of Es3 and Es4s reservoir in Minfeng sag was approximately A1 stage of meso rock. Reservoir pore space was mainly secondary solution pore. Reservoirs in Es4s formation are predominately glutenite fans lithologic reservoirs, while reservoirs in Es3z formation are predominately turbidite lithologic reservoirs. The distribution and abundance of hydrocarbon are mainly controlled by macroscopic structural background, sedimentary facies, reservoir thickness, sealing, pressure and complex fault structure styles. The outlook that sideway sealing by root fan subface is proposed, the method how to explore nearshore subaqueous fans reservoir changed from structural reservoir to lithologic reservoir.Overall, 21favorable exploration targets are proposed, and 12 of them are deployed for exploration, additionally, the reported dominate geological reserves are 48,840,000 ton, while the predicted geological reserves are 10,110,000 ton.更多还原