长岭断陷龙凤山地区营城组沉积相特征研究

发布时间：2018-07-26 10:14

【摘要】：长岭断陷龙凤山次凹营城组砂体发育,且毗邻烃源岩,储层的含气性好,具有广阔的勘探前景。由于龙凤山次凹仍处于勘探的初期,沉积相及物源的研究仍有待深入。在岩心、测录井、地震及薄片资料分析的基础上,对其中物源分布、沉积相类型及有利相带进行了深入研究,取得以下成果:在物源分布方面,通过对碎屑颗粒组分、重矿物组合特征、Q型聚类分析及砾岩/砂岩百分含量分布的研究,认为龙凤次凹营城组沉积期物源具有东西分区、中部混源的特征,且东西物源成分上存在差异,其中西南物源以火山岩和变质岩为主,东南物源主要为火山岩。在沉积相分布方面,在沉积相标志研究的基础上,建立龙凤山地区不同沉积微相的识别标准,明确研究区在西南缓坡带发育辫状河三角洲沉积,东南陡坡带发育扇三角洲沉积。其中,扇三角洲沉积特征兼具重力流与牵引流的沉积特点,沉积物成熟度低,地震上表现为杂乱反射及前积反射。辫状河三角洲沉积以牵引流搬运为特征,不发育重力流砂体,且形成的规模大,向湖盆方向推进距离远,在地震上具有典型的S型前积的特征。在单井相、剖面相及平面相研究的基础上,明确了研究区沉积相的平面分布及纵向演化特征。从营Ⅳ-2小层到营Ⅳ-1小层沉积阶段,为湖盆的扩张期,此时扇三角洲发育规模大,其前缘与辫状河三角洲前缘相互叠加,呈朵叶状分布。营Ⅲ砂组沉积期,湖盆进入了逐渐萎缩阶段,盆地主要发育以辫状河三角洲为主的沉积体系,扇三角洲规模小,辫状河三角洲平原沿F4断层广泛分布,前缘呈条带状分布。在沉积相研究的基础上,综合利用物性测试、CT扫描、恒速压汞及铸体薄片等方法,确定了龙凤山地区有利储集相带形成机理与分布特征。其中三角洲外前缘的(含砾)细砂岩受早期碱性水的控制,早期浊沸石胶结发育,同时毗毗邻烃源岩,有利于后期有机酸的进入与油气的充注成藏,是研究区的有利储集相带。
[Abstract]:The sand body of Longfengshan subconcave Yingcheng formation in Changling fault depression is developed and adjacent to the source rock. The reservoir has good gas-bearing property and has broad prospect of exploration. Since the secondary depression of Longfeng Mountain is still in the early stage of exploration, the study of sedimentary facies and source remains to be further studied. Based on the analysis of core, logging, seismic and thin slice data, the distribution of source materials, types of sedimentary facies and favorable facies zones are studied in depth. The following results are obtained: in the distribution of source materials, the components of clastic particles are analyzed. Q cluster analysis of heavy mineral assemblage and study on the percentage distribution of conglomerate / sandstone, it is concluded that the sedimentary source of Longfengciao Yingcheng formation has the characteristics of east-west division, central mixed source, and the difference of east-west source composition. Volcanic rocks and metamorphic rocks are the main provenance in the southwest and volcanic rocks are the main source in the southeast. In terms of sedimentary facies distribution, based on the study of sedimentary facies markers, the identification criteria of different sedimentary microfacies in Longfengshan area were established, and the braided river delta deposits developed in the study area in the southwest gentle slope zone and fan delta deposition in the southeastern steep slope zone. The sedimentary characteristics of fan delta are characterized by both gravity flow and traction flow. The sediment maturity is low, and the seismic features are disorderly reflection and forward reflection. The braided river delta deposit is characterized by traction current transport, no gravity flow sand body, large scale of formation and long distance to the lake basin. It has the characteristic of typical S type foreshadowing on earthquake. Based on the study of single well facies, profile facies and plane facies, the plane distribution and longitudinal evolution characteristics of sedimentary facies in the study area are determined. The sedimentary stage from Ying-鈪，

本文编号：2145670