苏里格气田南区二叠系山1-盒8沉积相及测井特征对比研究.pdf

苏里格气田南区二叠系山1-盒8沉积相及测井特征对比研究摘要：苏里格气田南区二叠系山1二叠系盒8气储层的综合分析研究表明，鄂尔多斯二叠系山1期为曲流河三角洲沉积，以三角洲前缘亚相沉积最为发育，主要发育水下分流河道和水下分流间湾微相等微相，水下分流河道砂体是天然气储集的骨架砂体。二叠系山1和二叠系盒8气储层沉积相存在差异，但曲线形态基本相同，砂岩的电测曲线特征为箱状、钟状，自然伽玛曲线幅度较低，齿化较少，二叠系山1气储层在电性上表现为低伽玛、低密度、高时差特点（储层好）；二叠系盒8段储层整体表现为一套低伽玛、高电阻的电性特征。关键词：鄂尔多斯盆地；二叠系；油气储层陈志华1，常 森2（1.长庆油田公司苏里格气田研究中心；2.长庆油田公司第五采气厂）0前言鄂尔多斯盆地是我国西部中、新生代大型陆相沉积盆地之一，二叠系山西组是盆地内主要的含气层系。苏里格南部地区主要勘探面积约9000km2，发育上古生界二叠系石盒子组盒8段和山西组山1段大型河流三角洲砂岩岩性圈闭气藏，与苏里格气田本部具有大致相同的沉积体系和沉积背景，储层物性参数与苏里格气田本部基本一致，具有巨大的开发潜力。该区上古主要目的层系为下石盒子组盒8段和山西组山1段。1 区域构造及演化特征鄂尔多斯盆地是我国大型沉积盆地之一，构造简单，总体显示为一东翼宽缓，西翼陡窄的不对称大向斜的南北向矩形盆地。根据盆地现今构造形态，基底性质及构造特征，鄂尔多斯盆地可划分出伊盟隆起、渭北隆起、晋西挠褶带、陕北斜坡、天环坳陷及西缘冲断构造带六个构造单元123。鄂尔多斯盆地基底由太古界及元古界变质岩组成，沉积盖层仅缺失志留系和泥盆系。按其构造层及古地理发育特征，鄂尔多斯盆地构造演化可大致划分为中晚元古代坳拉谷、早古生代浅海台地、晚古生代滨海平原、中生代内陆盆地和新生代周边断陷（如图2）。地质应用 作者简介：陈志华（1977），男，2000年毕业于西北大学矿产普查与勘探专业，硕士。气田开发工程师，主要从事气藏评价地质综合研究工作。石油工业计算机应用COMPUTER APPLICATIONS OF PETROLEUMMarch.20232023年3月图1 苏里格气田南区山西组山1位置1032023年3月石油工业计算机应用图2 鄂尔多斯盆地构造单元分布图2二叠系山1气层沉积相及测井特征I.测井相基础类型山西组以“北岔沟砂岩”之底为底界，以“骆驼脖砂岩”之底为顶界，整合沉积于太原组之上，厚度约80m110m，向西略有减薄趋势。根据沉积旋回和岩性组合特征，自下而上可分为山2、山1两段。山1期内以分流河道沉积的砂岩为主，砂岩由石英砂岩、中-粗粒岩屑石英砂岩组成，地层厚度一般40m50m，是该区主要含气层之一。山1期在苏南区为三角洲前缘亚相沉积（如图2），水下分流河道相对较窄，河道间发育分流间湾泥岩沉积。根据砂体沉积成因，盒8、山1单套连续砂体可分为水下分流河道正韵律（主河道），水下分流河道侧翼，河口坝反韵律（如图3）。1.1 储层特征苏里格气田南一区上古生界山1段含气层储层为三角洲前缘水下分流河道沉积砂体。盒8期受多期河道摆动、迁移及多韵律沉积控制，砂体纵向上叠置厚度大，平面上复合连片，厚度普遍大于15m，局部可达 30m40m，主砂体宽度一般 10km20km，延伸长度在150km以上。与盒8期相比，山1期水动力条件相对较弱，砂体规模较小，主砂体呈近南北向条带状展布，厚度 10m20m，宽度 8km15km，南北向延伸长度100km左右（如表1）。1.2 砂体纵向分布模式根据砂体沉积成因，盒8、山1单套连续砂体可分为水下分流河道正韵律（主河道），水下分流河道侧翼，河口坝反韵律。根据砂体纵向组合方式可分为四种类型。a块状厚层砂体，单层砂厚8m，砂地比大于50%，气井产量高；b多层叠置砂体，单层砂厚4m，夹层2m，总砂厚8m，砂地比大于40%，气井产量较高；c分段互层砂体，单层砂厚4m，夹层2m，总砂厚8m，砂地比大于40%，气井产量较低；d薄互层砂体，单层砂厚 4m，夹层2m，总砂厚8m，砂地比40%，气井产量低。II、二叠系山1沉积相展布特征苏里格气田南区山西组山1段主要发育曲流河三角洲前缘沉积亚相。北部-中部地层水下分流河图3二叠系山1水下分流河道相沉积模式示意图表1 苏里格气田南一区山1气藏储层特征简表1042023年3月陈志华，等：苏里格气田南区二叠系山1-盒8沉积相及测井特征对比研究道发育，局部发育小范围的河口坝沉积，与盒8段相比，山1段分流河道规模变小，砂体间水下分流间湾泥岩沉积相对发育（如图5）。III、二叠系山1气储层岩心构造特征沉积构造是指沉积物沉积时，或沉积之后，由于物理作用、化学作用及生物作用形成的各种构造，是划分沉积相的重要依据。该区发育的沉积构造主要有水平层理、斜层理、砂纹层理、波状层理、虫孔构造、冲刷面构造。从沉积构造来分析，无大型交错层理，说明该期水动力条件相对较弱，从沉积的砂、泥岩中所含的植物化石和煤线来看，沉积时湖水水深较浅（如图6）。3 苏里格气田南区盒8气层沉积相与测井特征I.二叠系盒8气储层沉积相特征苏里格气田盒8气藏是一个典型的低压、低渗、低丰度的岩性圈闭气藏，在加里东期后，在鄂尔多斯盆地出现了南北隆起，中部低坳的古地理格局，苏里格气田古地形呈现北高南低、东高西低的西倾大单斜，下石盒子期水系主体由北向南发育的特征（如图7）。采用岩石学、古生物学和地球物理学等方法，并以沉积旋回和测井资料的对比为主要手段，即将岩性和测井资料相结合，将苏里格气田东区盒8砂层组自下而上划分为盒8下2、盒8下1、盒8上2及盒8上1共4个小层4567。如前所述，河流相是研究区盒8上、盒8图4 二叠系山1水下分流河道相砂体纵向分布模式图图5 山1水下分流河道微相沉积模式示意图图6 二叠系山1气储层岩心构造特征图描述：深灰色泥岩中夹砂岩，泥砂间互，软沉积变形构造层位：山12 苏X。描述：厚层粉砂岩，对称浪成沙纹层层位：山12井名：苏Z。1052023年3月石油工业计算机应用下的主要沉积类型，包括辫状河沉积和曲流河沉积。盒8上和山1曲流河沉积涉及的沉积微相主要有：河道滞留沉积、边滩、天然堤、决口扇、废弃河道和泛滥平原；盒8上与盒8下辫状河沉积涉及的沉积微相主要有：河道滞留沉积、心滩、泛滥平原（如表1）。II、典型单井沉积微相分析西部选取1口单井苏1x井（如图8），苏1x井位于研究区西部，盒8上亚段以粗砂岩为主，自然伽马曲线呈明显厚层状箱型和齿状钟形叠加，为辫状河心滩和河道的沉积特征，盒8下亚段主要为泥岩沉积，自然伽马曲线为低幅齿状，符合间湾和漫溢砂沉积特点。研究区西部整体垂向上从盒8下亚段到盒8上亚段为水体变浅的过程，同层位从北向南，砂岩厚度略减薄，河道宽度变窄，出现河口坝，指示研究区沉积环境从北向南有从水上到水下的变化。东部选取两口典型单井苏 1y 进行分析（如图9），苏1y井位于东部偏北，自然伽马曲线在盒8下亚段主要为厚层齿状箱型和低幅线性为主，且规模逐渐减小，指示主体河道垂向的变迁，盒8上亚段发育一套略呈反粒序的齿状漏斗形和箱型的叠加，指示在该时期河道发育期次和规模都略少于盒8下亚段。北部选取两口典型单井陕 3z 进行分析（如图10），陕3z井位于研究区北部偏东，目的层段盒8段自然伽马曲线主要为厚层箱型和齿状钟形叠置，指示研究区北偏东部是物源的主要方向，在整个盒8段沉积期都是河道相对发育地区。III、测井相识别本次研究根据现有资料，采用利用自然伽马曲线形态特征方法来进行分析。不同的沉积环境下，由于物源情况不同、水动力条件不同及水深不同，必然造成沉积物组合形式和层序特征（正韵律、反韵律、复合韵律）的不同，反映在测井曲线上就是不同的测井曲线形态。根据区内二叠系区域沉积特征，对工区内130余口井的自然伽马曲线特征进行分类统计，按照砂体对应的自然伽马曲线形态特征以及砂泥岩界面处自然伽马曲线的变化特征可以划分出6种沉积微相的测井相（表2）。并就主要的2中微相做简单的陈述。河道沉积相河道滞留沉积常发育在河道底部，底面冲刷严重，含泥砾，常具叠瓦状定向排列，倾向指向上游。图7 苏里格气田东区盒8沉积模式图表1 苏X井区沉积微相类型与特征表1062023年3月一般呈透镜状断续分布于河床最底部，向上过渡为边滩或心滩沉积。GR曲线表。现为大套箱形和钟形底部的高幅小钟形和小漏斗形。心滩相心滩主要发育在辫状河中，其GR测井曲线形态主要表现为高幅锯齿状或者光滑状的箱形，其顶底均呈现出突变的接触关系。锯齿状箱形反映了水动力条件强但不稳定，强弱频繁交替的特征，在工区内这种类型比较常见；光滑状箱形反映了物源充足、强而稳定的水动力特征。4结论（1）研究表明鄂尔多斯二叠系山1期为曲流河三角洲沉积，以三角洲前缘亚相沉积最为发育，主要发育水下分流河道和水下分流间湾微相等微相，水下分流河道砂体是研究区天然气储集的骨架砂体。（2）二叠系盒8砂岩沉积物来源受阴山古陆老变质岩系和海西期兴蒙褶皱带共同组成的物源区控制，储层砂岩主要以岩屑石英砂岩、岩屑图8 苏1x单井沉积微相综合柱状图图9 苏1y单井沉积微相综合柱状图图10 陕3z单井沉积微相综合柱状图陈志华，等：苏里格气田南区二叠系山1-盒8沉积相及测井特征对比研究1072023年3月石油工业计算机应用砂岩为主，其次为石英砂岩。盒8段石英含量比较高，长石含量低。（3）二叠系沉积体系特征盒8段以辫状河沉积体系为主。平面上均发生河流类型的转化，由于这种河型转换变化造成砂体与泥岩厚度、宽度的扩大与缩小，这是造成产气层差异大的因素之一。参考文献：1 赵红格、刘池洋，物源分析方法及研究进展，沉积学报，Vol21No3Sep，20032 梅志超，沉积相与古地理重建M.西安.西北大学出版社，1994，962383 郭艳琴等，陇东地区三叠统延长组早中期物源分析与沉积体系，煤田地质与勘探，20054 沈玉林,郭英海,李壮福.鄂尔多斯盆地苏里格庙地区二叠系山西组及下石盒子组盒八段沉积相J.古地理学报,2006,8（1）：5362.5 李会军,吴泰然,马宗晋,等.苏里格气田优质储层的控制因素J.天然气工业,2004,24（8）：1213.6 张明禄，李进步，安文宏等苏里格气田盒8段气藏有效砂体成因模式J天然气工业，2008增刊B812.7 Beard D C，Weyl P K Influence of texture on porosityand permeability of unconsolidated sandJ AAPG Bulletin，1973，57：349-369.表2 苏南沉积微相测井曲线形态一览表108COMPUTER APPLICATIONS OF PETROLEUMMar.2023ABSTRACTSABSTRACTS1 1.Machine Learning in the Petroleum Industry:GeoScience,Reservoir Engineering,Production Engineering.Machine Learning in the Petroleum Industry:GeoScience,Reservoir Engineering,Production EngineeringWang HonglinWang Honglin（7373）Abstract:Abstract:Artificial intelligence/machine learning（AI/ML）has become a major driver of emerging technologies such as big data,robotics,and theInternet of Things.Digital transformation extends deep into the oil and gas industry to reshape geoscience,reservoir engineering and productionengineering,seeking greater productivity in exploration and production（E&P）operations.AI/ML is the next technological breakthrough on the horizon.By leveraging AI/ML in oil and gas operations,algorithms can be designed to guide E&P.The AI/ML system will be trained using historical data fromE&P jobs.Keywords:Keywords:petroleum industry;exploration and production;artificial intelligence/machine learning,earth science,reservoir engineering;productionengineering,digital twin;Internet of Things2 2.The application of gravity,magnetic and magnetotelluric exploration technique to solid minerals in Tibet.The application of gravity,magnetic and magnetotelluric exploration technique to solid minerals in TibetLuo Wei-feng Wang Yongsheng Wang Caifu He lanfang Wang yaohuiLuo Wei-feng Wang Yongsheng Wang Caifu He lanfang Wang yaohui（9999）Abstract:Abstract:Through the research on methods of processing and interpretation of gravity,magnetic and magnetotelluric,the software of comprehensiveprocessing and interpretation has been developed and the comprehensive exploration processing and interpretation technology system has been formed.The technology system has been applied in the exploration of solid mineral in an area of Tibet.Based on the results of geophysical exploration on theground,the development of the large scale concealed chromite deposits in the deep or shallow concealed chromite is predicted and good results havebeen achieved.Key words:Key words:Comprehensive processing and interpretation hidden chromite prospecting effect.3 3.Analysis of logging curve and formation characteristics in eastern Sulige Gas field.Analysis of logging curve and formation characteristics in eastern Sulige Gas fieldChen zhihua changsenChen zhihua changsen（103103）Abstract:Abstract:Gas fields in China land is the largest ready natural gas,natural gas resource of 3.8 trillion cubic meters,but gas surface in a complex geologicalsituation,different thickness of gas layers,most of the store in sandstone gas reservoir,gas field development is very difficult,in this paper,combiningwith working practice,this paper discusses the gas mainly in formation characteristics and well logging curve in the formation of response law and how toaccurately stratified4 4.Research and development of integrated management system for mining rights.Research and development of integrated management system for mining rightsShen weigang Wang xiaoxingShen weigang Wang xiaoxing（115115）Abstract:Abstract:Oil and gas mining right is the prerequisite for oil and gas resources exploration and development according to law,and is the core asset of oilcompanies.As the embodiment of the value of mining rights,oil and gas reserves are the core assets of core assets,and protected areas are the areasrestricted by oil and gas exploration.Therefore,it is particularly important to understand the underground distribution of oil and gas reserves and thedistribution of protected areas in the mining rights block.In this paper,spring is used as the core framework of the business layer,the most popularenterprise java language application development framework in the industry,and the key technology of MAPGIS spatial data three-dimensional modelingis used to build a comprehensive management system of mineral rights,to find out the underground distribution of oil and gas reserves and thedistribution of protected areas in the mineral rights block,and effectively support the oil and gas exploration and development management of the OilfieldCompany;This paper will introduce the research and development of the system from the aspects of system analysis,design,implementation anddeployment.Keywords:Keywords:mining rights;Reserves;protected areas;MAGGIS spatial data;3D modeling.5 5.Application of linear programming in single well investment decision.Application of linear programming in single well investment decisionChen Xue and Li TingChen Xue and Li Ting（117117）Abstract:Abstract:When making decisions on new investment opportunities,oil companies are often faced with the problem of selecting high-quality oil fieldssuitable for the companys business objectives from multiple block oilfields,that is,they need to select oil fields with better expected benefits forinvestment.When evaluating whether the oilfield benefit meets the demand,the expected benefit of a new well is the key indicator.At present,most oilcompanies use the method of queuing with technical and economic indicators and taking expert opinions into account when making comparative analysisof the benefits of single wells.In the case of many oilfields and large number of planned wells,the simple queuing method is complex in calculation,andthe results need to be corrected repeatedly,which takes a long time and has a general effect.The linear programming method is used to evaluate andscreen all planned new wells.The calculation process is implemented by computer,which takes less time and has good effect.The planning solutionfunction in traditional Excel software can be realized.This paper takes 23 planned new wells in A oilfield of an oil company in Mississippi area of theUnited States as samples,and uses Excel planning solution tools to solve the new drilling portfolio under different objectives,so as to achieve the resultsof single well investment decisions.Keywords:Keywords:linear programming;single well investment decision;Excel programming solution tool