【作者】 赵伟；

【导师】 谭成仟；

【作者基本信息】 长安大学 ， 地球探测与信息技术， 2011， 硕士

【摘要】 下寺湾油田川道地区位于鄂尔多斯盆地陕北斜坡东南部,面积70km2。晚三叠系延长组长2油层组地层表现为自西向东逐渐抬升的平缓单斜,局部发育有近东西向的鼻状构造。本文围绕如何确定有利物性发育带及岩性圈闭这一核心任务,充分利用各种岩心、测井等丰富的静态以及动态资料,运用储层地质学、储层沉积学、测井地质学等相关学科理论,进行了长2油层组沉积微相研究,归纳了砂体展布的控制因素、进行了储层储集性能分析、储层分类评价及其与含油性的关系研究。在论文研究基础上对川道地区长2油层组主要取得以下认识：(1)根据地层对比原则,研究区长2油层组可分为长21、22和23三个油层亚组,主力产层段长22依据沉积旋回可进一步细分为长221、222、223三个小层。(2)为受东北物源控制的三角洲沉积环境,发育三角洲前缘亚相。结合区域地质背景,通过对测井相、岩石相的分析,识别出研究区长2油层组主要发育水下分流河道、河道侧翼和分流间湾三种沉积微相,其中水下分流河道是研究区主要储层。(3)砂岩以长石细砂岩为主,成分成熟度较低,结构成熟度中等。累计砂岩厚度为17.6～46.8米,砂体沿NE—SW向呈条带状分布,其分布范围主要受水下分流河道微相控制。(4)储层孔隙类型以粒间孔为主,其次是溶蚀粒间孔、粒内溶孔及局部发育的裂缝,孔隙结构较差。主要成岩作用类型为压实、胶结和溶解作用,长2油层组现主要处于晚成岩阶段的A期。(5)储层可划分为三类：Ⅰ类(好储层)、Ⅱ类(中等储层)、Ⅲ类(差储层)Ⅰ类、Ⅱ类储层岩性较纯,以细砂岩为主,含油性较好；Ⅲ类岩性以粉砂岩及灰质、泥质胶结较重的细纱岩为主,含油性差。更多还原

【Abstract】 Chuandao region of Xiasiwan oilfield locates in south-central of Shanbei flank belt in Ordos basin covering an area of 70 km. Chang 2 oil layer of late Triassic is an even slope uplifting from west to east gradually and locally developed low relief nose uplift structure. This article focuses on how to determine lithologic traps and development areas with good porosity and permeability so as to fully use core, well logging and abundant of static and dynamic data and reservoir geology, reservoir sedimentology, reservoir well logging theory to research micro sedimentary facies for Chang 2 oil layer, summarizes controlling factors of sandbody distribution, analyzes preserving capability of the reservoir and finally predicts favorable geologic target which provide geologic basic for next exploration deployment. Main understandings for Chang 2 oil layer of Chuandao region.(1) According to the principle of stratigraphic correlation, Chang 2 oil layer of Chuandao region of Xiasiwan oilfield would be separated into three oil sub-layer which including Chang 21、22、23.The key oil-bearing formation Chang 22 was further divided for Chang 221、222、223 by Sedimentary cycle.(2) It is delta sedimentary environments controlled by northeast sources. Sub facies of delta is developed. It will union area geology background, distinguishes out three kinds of micro sedimentary facies including subsea distributary channel, subsea distributary channel flank and interdistributary bay. The subsea distributary channel is mainly reservoirs in study area.(3) Mainly fine sandstone and coarse siltstone, low maturity for component and medium maturity for texture. Total thickness of sandstone is 17.6-46.8m, which spreads from northeast to southwest like banding is controlled by micro facies of subsea distributary channel in delta system.(4) Porosity types of the reservoinpredominantly intergranular pore,secondly innerg ranular corrosion pore and locally developed fissure which weak porous structure.Diage nesis types:mainly compaction, cementation and dissolution. Nowadays it is a period o f time A,terminal diagenesis for Chang 2 oil layer.(5) 3 types of reservoirs:I(good),II(medium)and III(bad).Lithology is pure forⅠand Ⅱ,mainlyfine sandstone;mainly siltstone and lime and mud cemented fine sandstone,generally oil-poor.更多还原