【作者】 李国斌；

【导师】 姜在兴；

【作者基本信息】 中国地质大学（北京） ， 矿产普查与勘探， 2009， 博士

【摘要】 以沉积学、层序地层学、测井地质学等理论为基础,综合运用地震、岩心、测井和录井等资料对东营凹陷西部沙四上亚段滩坝进行了解剖分析,建立了层序地层格架,在层序地层格架内对滩坝类型、沉积特征、平面展布、垂向演化及滩坝控制因素等进行了综合研究,建立了东营凹陷滩坝沉积模式和风动力砂体定量预测模型。主要成果与认识如下:(1)将东营凹陷沙四上亚段划分为一个三级层序3个体系域即低位体系域、湖侵体系域和高位体系域,并进一步将低位体系域划分为3个准层序组、湖侵体系域和高位体系域各划分为2个准层序组。(2)滩坝主要发育在低位体系域的3个准层序组内,湖侵和高位体系域滩坝发育差,但高位体系域部分井区发育碳酸盐滩坝。(3)滩砂单砂层厚度薄,泥岩夹层发育,主要沉积构造有波状-微波状层理、波状复合层理、低角度楔状层理、冲洗交错层理、脉状层理、透镜状层理和浪成沙纹层理等;主要层面构造有浪成波痕、干涉波痕、修饰波痕和浅水微波痕等;测井曲线主要表现为薄指形密集组合、单砂层呈高-中幅薄指状或“尖刀状”。(4)坝砂多分布在滩砂中,单砂层较厚,主要沉积构造有波状层理、楔状层理、平行层理和块状层理;层面构造有浪成波痕、剥离线理等;测井曲线主要表现为宽幅较厚指形、齿化漏斗形或齿化箱形。(5)建立了东营凹陷沙四上滩坝沉积模式即“气—源—盆”系统控滩坝模式,将东营凹陷西部滩坝分布划分为陡坡顺风带、中央振动带和缓坡迎风带三带分布区,并从水动力、物源、沉积物沉积及储层特征等方面进行了分析比较。(6)提出了博兴洼陷南部缓坡带滩坝受不同水动力带控制的机理,即冲浪回流带控制砾质滩坝和沿岸滩坝、碎浪带控制近岸滩坝、破浪带控制远岸滩坝;建立了风动力滩坝砂体定量预测模型,对不同水动力带坝砂体厚度、宽度及延伸长度进行了定量预测,并通过单砂层厚度统计法和连井砂体对比对预测模型及结果进行了检验验证,认为预测结果可靠,具有实用性。这也是首次用沉积学方法对薄砂体进行的定量预测,为薄砂体的定量预测提供了一种新思路。更多还原

【Abstract】 Based on the analysis of the seismic, core and well logs data and by using the theories of sedmentology, sequence stratigraphy and logging geology , this paper studied types, sedimentatary features, plane distribution, vertical evolution and controlling factors of beach and bar in the Upper Fourth Member of the Shahejie Formation of the Palaogene in the western Dongying Sag, and established the depositional model and the quantitative predicting model of beach and bar . The main achievements are as follows:(1) The Upper Fourth Member of the Shahejie Formation in the Dongying Sag is divided into one sequence with three systems tracts (lowstand systems tract, transgressive systems tract and highstand systems tract), and further subdivided into seven parasequence sets .(2) The beach and bar in the three parasequence sets of lowstand systems tract are well developed but poorly developed in transgressive systems tract and highstand systems tract .(3) The beach single sand layer is relatively thin and the mudstone interbedded is well developed. The main sedimentary structures are wave-microwave beddings, wave mixed beddings, low angle wedgelike beddings, swash cross beddings, veinlike beddings, lenticular beddings, wave-formed sand ripples beddings and so on. The main bedding surface sedimentary structures are wave-formed ripples, interference ripples, decorated ripples and shallow water microwave ripples and so on. Well log features of the beach are thinly finger crowd association curve, thinly finger or sticker-shape curve with high-middle amplitude .(4) The bar distributes in the beach, the single sand layer is relatively thick and the mudstone interbedded is poorly developed. The main sedimentary structures are wave beddings, wave mixed beddings, wedgelike beddings, parallel beddings and massive beddings and so on. The main bedding surface sedimentary structures are wave-formed ripples, parting lineations and so on. Well log features of the bar are wide amplitude finger, jagged infundibuliform or jagged box form .(5) The system of‘paleoclimate-provenance-basin’controlling beach-bar model is established. In this model, the distribution areas of beach-bar are divided into three zones, namely the northern steep slope leeward zone, the center shaking zone and the southern gentle slope windward zone. In these zones, its features in hydrodynamic, provenance, sedimentation and reservoir are different, and have been analysed in detail in this study.(6) In this paper, the author proposes the beach-bar on the southern gentle slope in the Boxing sag is controlled by different hydrodynamic zones, namely the surfing- backflowing zone controls the pebbly beach-bar and inshore beach-bar, the breaker zone controls nearshore beach-bar and the broken zone controls infralittoral shore beach-bar. The quantitative predicting model of the beach-bar is also built up. The thickness, width and length of the sandy bar in different hydrodynamic zones are quantitatively predicted. By using statistics of single bar sandy layer thickness and well tie correlation of sandbodies, the predicted results are tested and proved to be reliable and effective. This method is the first time using sedmentology, and is an improvement and supplement for thin sandbodies quantitative prediction, and also provides a new insight on the prediction of thin sandbodies .更多还原