鄂尔多斯盆地延长组湖盆充填结构及致密储层预测

发布时间：2018-04-26 22:07

本文选题：前积反射 + 湖盆充填　；参考：《西北大学》2015年硕士论文

【摘要】：近年来随着鄂尔多斯盆地黄土塬地区地震资料品质的不断提高,在地震剖面上显示出了许多延长组湖盆地层学和沉积学方面的重要信息。其中延长组不同方向大型前积反射指示的斜交前积充填过程可以较好的解释了湖盆中心长7重力流砂体的来源和分布等成因。本文综合了地震和钻井资料,在合成记录层位标定和地震资料精细解释的基础上,探讨了鄂尔多斯盆地延长组湖盆充填模式以及其对长7-长6致密储层控制作用,建立了不同组合类型致密砂体测井相模式,通过测井响应、地震正演、地震反演、属性分析等多种手段开展了致密储层的识别与预测,并取得了以下几点认识：1、延长组湖盆并不是像钻井分层那样“千层饼”式的加积充填的,而是由来自不同方向和坡度的长7-长6、长7-长4+5或长7-长3时期大型三角洲-重力流斜交前积充填的。长7致密砂体主要来自西南陡坡长6-长3时期的三角洲滑塌重力流成因。2、通过建立研究区致密砂岩的含油性解释标准,确定了致密砂岩的物性、含油性、岩性和电性等参数,分析了致密砂体的分布、测井相类型、储源组合等特征。3、砂体正演结果表明,长7低速页岩上发育一套或多套砂体,在地震剖面上,长7底强振幅之上会出现一个中弱振幅,致密砂体厚度与振幅强弱成正比。4、叠后自然伽马可以区分出致密砂岩与泥岩,密度反演小于2.56g/cm3砂体可能为致密油。在井约束条件下,通过叠后自然伽马反演与叠后密度反演相结合的方法,可以较好的预测致密储层。
[Abstract]:In recent years, with the continuous improvement of the quality of seismic data in the Loess Plateau area of Ordos Basin, many important information on stratigraphy and sedimentology of the lake basin of Yanchang formation have been shown on the seismic profile. The process of oblique forward filling indicated by large forward reflection in different directions of Yanchang formation can explain the origin and distribution of gravity flow sand body of Chang 7 in the center of the lake basin. In this paper, the seismic and drilling data are synthesized, and on the basis of the calibration of synthetic record horizon and the fine interpretation of seismic data, the filling model of lake basin of Yanchang formation in Ordos Basin and its controlling effect on the tight reservoir of Chang7-Chang6 formation are discussed. The logging facies models of different types of compact sand bodies are established, and the identification and prediction of tight reservoirs are carried out by logging response, seismic forward modeling, seismic inversion, attribute analysis and so on. And we have gained the following understanding: the Yanchang formation lake basin is not a "thousand layer cake" type of accretion filling like drilling stratification. Instead, it is filled with large delta gravity flow oblique forward deposits from different directions and slopes in the period of 7- Chang 6, Chang 7 Chang 45 or long 7 Chang 3. The dense sand body of Chang 7 is mainly derived from the origin of the delta slump gravity flow in the period of Chang 6-3 in the southwest steep slope. By establishing the interpretation standard of the oil content of the dense sandstone in the study area, the physical properties, oil content, lithology and electrical properties of the dense sandstone are determined. The distribution of tight sand bodies, the type of logging facies and the combination of reservoir and source are analyzed. The forward modeling results of sand bodies show that one or more sets of sand bodies are developed on Chang7 low speed shale. In seismic profile, there will be a middle and weak amplitude above the strong amplitude at bottom of Chang 7. The thickness of compact sand body is proportional to the amplitude of sand body. The natural gamma ray can distinguish dense sandstone from mudstone. The inversion of density is smaller than that of 2.56g/cm3 sand body, which may be a tight oil. Under the condition of well constraint, the method of combining natural gamma inversion with post-stack density inversion can be used to predict the tight reservoir.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13

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