2007年12月 第29卷 第6期石油天然气学报(江汉石油学院学报)
Dec 12007 Vol 129 No 16Journal of Oil and G as T echnology (J 1J PI ) ・49・
三角洲前缘河口坝储层构型界面层次表征
李云海, 吴胜和, 李艳平 (中国石油大学(北京) 资源与信息学院, 北京102249)
程会明, 辛志国 (胜利油田有限公司地质科学研究院, 山东东营257015)
赵红兵, 崔文富 (胜利油田有限公司胜利采油厂, 山东东营)
[摘要]以高分辨率层序地层学和储层构型理论为指导, , 8砂组河
口坝砂体构型界面进行了层次表征。8、17个短期基
准面旋回。在等时地层格架内, :5级界面常发育稳定的前三角洲泥
岩, ; 4、粉砂质泥岩组成, 形成流体渗流屏障; 3级界
。利用密井网区的动态
。构型界面的层次表征揭示了储层内部复杂的构型界面对剩余
, 为剩余油的挖潜指明了方向。
[关键词]高分辨率层序地层学; 三角洲; 河口坝; 构型界面; 层次分析; 渗流屏障; 胜坨油田
[中图分类号]TE12113; TE19[文献标识码]A [文章编号]100029752(2007) 0620049204
构型是指沉积砂体内部由各级次沉积界面所限定的砂质单元和不连续“薄夹层”的几何形态、规模大小、相互排列方式与接触关系等结构特征。目前, 野外露头和现代沉积的构型研究已取得一定进展[1], 但地下储层的构型研究受资料所限, 仍在起步阶段[2,3]。构型应用于河流、风成和深水沉积物相模型中, 被认为是一个合理成熟的方法, 而三角洲沉积的构型分析研究不足。
沉积体的沉积界面等级概念及分级体系已广泛应用于储层沉积学研究领域中, 成为认识沉积体内部构型的一种有效方法。利用不同规模的界面, 可将地层分成一系列的三维沉积单元, 既有利于分类描述, 也有利于研究各级沉积作用的规模和持续时间[4]。笔者依据构型理论和层次分析方法, 对胜二区沙二段8砂组河口坝储层构型界面进行层次表征, 建立储层内部构型界面分布模型, 为河口坝储层非均质性研究和剩余油挖潜提供方向。
1 高分辨率层序地层格架
胜坨油田位于济阳坳陷东营凹陷北部, 陈家庄凸起南端, 是一个逆牵引背斜构造油田。主要断层将胜坨油田分割成胜一区、胜二区和胜三区3个区, 其中胜二区位于胜坨油田中部, 是一个北部和东部被断层切割、西南部与边水相连的扇形断块油藏。沙二段是主力含油层系, 共分为15个砂层组。详细的沉积环境研究表明, 沙二段时期发育河控湖相三角洲沉积, 其中沙二段8砂组砂体是典型的三角洲前缘沉积, 以发育厚层的河口坝砂体为特征。沉积微相的研究成果大量被国内外专著引用, 但储层构型的研究尚很少[5]。高含水开发后期, 常规的沉积微相研究已不能满足胜二区沙二段8砂组剩余油挖潜的需要, 必须精细研究储层内部构型特征, 揭示储层内部小尺度的非均质性。
通过大量的单井和连井剖面精细分析和对比, 采用以高频沉积旋回对应的湖泛面为界划分高精度层序地层单元的分析方法, 在沙二段8砂组识别出3个中期基准面旋回、17个短期基准面旋回。中期基准面旋回均为基准面下降的不对称半旋回, 对应于3个水体向上变浅的过程。短期基准面旋回的划分与井间对比充分考虑了三角洲前缘沉积的斜坡(clinoform ) 特点, 以斜坡的空间发育特点为参考, 追踪 [收稿日期]2007208210
[基金项目]中国石油化工集团公司重大科技攻关项目(P01035) 。
河口坝的顶面。以高分辨率层序地层学划分结果为依据, 将沙二段8砂组地层细分为3个小层和17个韵律层。三角洲前缘河口坝在空间上具有向盆地前积、不同时期河口坝垂向叠加、侧向相连的特点, 所以每个韵律层的发育范围有限, 单井在每个小层平均钻遇3～5个韵律层不等。
2 构型界面层次分析
211 层次界面分级
岩心上构型界面级次的识别、划分, 键[6]。为了进一步揭示沉积体内部沉积层次, 对沙二段8划分, 从小到大共划分出如下5级界面(图1)
。
图1 三角洲前缘河口坝砂体层次界面分级
1) 1级界面 为交错层系的界面, 即由一系列相同纹层组成的界面, 界面的方向与古水流的方向有关。其特点是没有明显的侵蚀作用, 侧向上可被更高级次界面截蚀。在8砂组储层中, 主要表现为低角度斜层理层系界面、板状交错层理层系界面、平行层理层系界面和波状交错层理层系界面等。
2) 2级界面 为层系组界面, 反映流动条件或流动方向的变化, 是砂体内部不同岩相之间的分界面, 在侧向上可被更高级界面削蚀。界面方向与古水流的变化有关, 且河口坝砂体不同部位的界面方向也不同。与1级界面的区别是界面上下的岩相发生变化。
3) 3级界面 为单一河口坝砂体内部增生体的顶、底界面, 界面向湖心方向倾斜, 其上披覆着短暂间洪期沉积的薄泥质夹层, 薄泥层界面上下的岩相组合相似。此类界面反映了河口沉积作用的短暂变化, 如河水流量的变化、负载的增减或湖水的季节性涨缩等。
4) 4级界面 为多个河口坝增生体叠合形成的单一河口坝的顶界面, 界面亦向湖心方向倾斜, 是三角洲朵体废弃后, 水体加深的间湾沉积形成。4级界面是8砂组三角洲前缘河口坝沉积的各韵律层分界面, 界面上下的岩相明显不同。界面横向延伸长度较大, 基本覆盖下伏的单一河口坝砂体, 顶部可以被更高级界面削蚀, 底部常可与三级界面重合或合并。
5) 5级界面 为多个单一河口坝垂向叠加与侧向叠合形成的河口坝复合体的顶界面, 是8砂组三角洲前缘沉积体中识别出来的最高级别的沉积界面, 为主要的侵蚀或洪泛面。界面向湖心方向倾斜, 多为平坦或略微波状起伏, 延伸范围广, 分布稳定, 覆盖整个研究区, 由三角洲朵体的迁移或水下分流河
由上述可知, 5级界面限定整个研究区, 是主要的侵蚀或洪泛面; 4级界面通常定义单一河口坝坝体; 3级界面分隔三角洲前缘河口坝层序内部的增生体; 1～2级界面只在岩心中可识别, 常规测井资料无法识别, 因此不做进一步研究。界面的级别在空间上可能发生侧向渐变, 任何级别的界面都可能被同级别或更高级别的界面削截, 但不会被更低级别的界面削截。
212 构型界面识别
不同层次的构型界面上下均分布着细粒的沉积, 如粉砂质泥岩、泥岩或成岩作用形成的钙质砂岩, 形成隔夹层, 隔夹层对流体渗流及原油采收率的影响很大, 是储层内部非均质性的主要地质因素, 同时也是识别构型界面的关键。
按照构型研究的层次性原则, 对应于3～5级层次界面, 共分为3级隔夹层。Ⅰ级为单一河口坝增生体之间的夹层, , 014m , 自然电位(SP ) 与自然伽马(GR ) 曲线轻微回返, 夹层侧向延伸范围有限, 局部可被后期洪水冲蚀而未保存, , ; Ⅱ级为单, , 物性较差, 可对流体渗流起屏障作用, 厚度012～110m , 曲线幅度差中等; Ⅲ级为河口坝复合体之间的厚层前三角洲泥质层, SP , ML 曲线无幅度差, 延伸范围广, 不具渗透性, 是有效的隔层。
通过取心井岩电标定, 在未取
心井中识别出各级次隔夹层, 进而
在单井中划分出3～5级构型界面。
213 构型界面的开发响应
对于沙二段8砂组而言, 3～4
级界面对于开发后期的意义更重要,
因为3～4级界面是层内剩余油的主
要控制因素, 纵向剩余油的分布与平
面剩余油的富集均与3～4级界面相
关。利用研究区密井网的动态监测资
料, 可揭示构型界面的存在, 分析构
型界面控制的剩余油分布。
1) 重复地层测试RFT 2003年
1月2日1X174井RFT 压力测试成果
揭示了4级界面对储层的分隔性(图
2) 。211410m 附近为一个4级构型界图2 1X 174井RFT 测试成果图
面, 分隔815与816韵律层, 界面处
的岩性为泥岩与粉砂质泥岩, 厚度约
112m 。构型界面之下的薄层低渗透远
砂坝砂体地层压力低于界面之上的厚图3 22188井吸水剖面成果图
层高渗透河口坝主体地层压力, 说明
此处4级构型界面对地下流体的渗流起主要控制作用, 将储层分割为两个独立的流动单元, 下部的远砂坝砂体动用程度高于上部的河口坝主体。据此分析, 河口坝主体仍有剩余油分布。
2) 吸水剖面 1998年7月4日22188井吸水剖面揭示3级界面影响剩余油分布(图3) 。832韵律层内部存在一个低渗透的3级构型界面(217114m ) , 界面上下吸水状况差异很大, 上部河口坝砂体渗透率级差小, 注入水在重力作用下, 易下沉至构型界面之上; 下部河口坝砂体渗透率级差大, 重力作用不明显, 注入水优先沿顶部高渗透砂体流动, 即在构型界面之下流动, 造成构型界面上下吸水强度大, 剩余油相对不富集。
・52・ 石油天然气学报(江汉石油学院学报) 2007年12月3 构型界面层次建模
构型界面层次建模的关键是井间预测问题。沙二段8
砂组的密井网检查井区有丰富的静态与动态资料, 为构
型界面的井间预测和层次建模提供了保障。由于3级与4
～5级构型界面的分布特点不同, 分2个层次建立构型界
面模型。先建立4级/5级构型界面三维模型, 在此模型
限制下, 选择资料丰富的井组, 的构型界面展布, 建立3级构型界面的剖面模型。
4级/5级构型界面的分布范围广, 层易于识别, , 图4 81小层4级/5级界面三维空间分布模型, 采
(图4) 。4级/5级构型界面模型反映81小层沉积时期, 砂体, 同时, 亦向西北方向迁移。4级构型界面限定的砂体呈透镜状。
根据22188井示踪剂监测结果推断韵律层内部3级构型界面的分布, 建立了示踪剂监测井组的3级构型界面剖面模型(图5) 。由于3级界面存在和钙质夹层的遮挡, 2
2188井注入的示踪剂未在32197和32199井检测出。3级界面的延伸范围有限, 泥质夹层的发育不均匀, 依据地下资料进行井间预测难度很大, 目前还不能在全区范围内建立模型。
图5 83小层3级界面剖面分布模型
4 结 论
1) 5级界面构成小层间的隔层, 4级界面作为渗流屏障, 将单一河口坝分割成相对独立的流动单元, 3级界面对流体渗流具有遮挡与缓冲作用。3级与4级界面伴生的泥质或泥质与钙质夹层组合体对剩余油的分布起决定作用。
2) 通过实例分析说明, 表面并不复杂的成熟油田仍具有进一步挖潜的机遇。构型界面分析是识别储层非均质性的有效方法。
[参考文献]
[1]王振奇, 何贞铭, 张昌民等1三角洲前缘露头储层层次分析———以鄂尔多斯盆地东缘潭家河剖面为例[J]1江汉石油学院学报,
2004, 26(3) :32～351
[2]李阳1我国油藏开发地质研究进展[J]1石油学报, 2007, 28(3) :75～791
[3]刘自亮1辫状河三角洲前缘厚层储集砂体沉积学研究[D ]1兰州:中国科学院研究生院(兰州地质研究所) , 20041
[4]王俊玲, 任纪舜1嫩江现代河流沉积体岩相及内部构形要素分析[J]1地质科学, 2001, 36(4) :385～3941
[5]何文祥, 吴胜和, 唐义疆等1河口坝砂体构型精细解剖[J]1石油勘探与开发, 2005, 32(5) :42～461
[6]马世忠, 王一博, 崔义等1油气区水下分流河道内部建筑结构模式的建立[J]1大庆石油学院学报, 2006, 30(5) :1～31
According to t he analysis above , it is concluded t hat t here are t hree areas for secondary oil explora 2tion , it is very hopef ul to find some geological reserves and it is of great significance for imp roving oilfield p roduction outp ut and reserves 1
K ey w ords :Biyang Dep ression ; nort hern slope ; oil and gas ; enrichment rules ; secondary exploration 33V olcanic Logging R ecognition in R eservoir Analysis
Y ANG Shen 2gu (Faculty of Resources , China University of Geosciences , W uhan 430074, Hubei , China; College of Geosciences , Yangtze University , J ingz hou 434023, Hubei , China )
LI U X iao 2cui (N o 12Oil Production Plant , Zhongy uan Oil f iel d Com pany , S I N O P EC, Puy ang 457532, Henan, China )
(H U Zhi 2hua College of Geosciences , Yangtze University , J ingz hou 434023, H ubei , China )
FAN Zhen , X U Jiang 2tao , CAO Zuo (X inj iang Oil f iel d Com pany , CN PC, Karam ay 834000, X inj iang , China Abstract :In t he process of volcanic oil and gas , objective rea 2sons , t here existed insufficient lit hologic , which con 2st rained t heir exploration and develop ment 1On t of volcanic rocks was simplified for reservoir analysis , of simplified volcanic types used in co nventional logging It t hat t he types of conventional logging curves wit h better , DEN , R T (RXO , RS , COND ) , GR and CAL 1Generally t presented high gamma ray , while volcanic clastic rocks and lava p , high density and low interval t ransit time 1In lava zones , logging curve p lava break , it reflected high interval transit time and low density and low 1By integrating data from oilfields , chart board and criterion are established for logging recognition 1The analytical met hod , idea and chart board are of great significance for t he basic st udy of volcanic reservoirs 1
K ey w ords :volcanic rock ; oil and gas pool ; reservoir ; lit hologic recognition ; logging data
38Characteristics of J 2q Source R ocks in K uqa Depression
LI Qian (Faculty of Energy Resources , China Universit y of Geosciences , B ei j ing 100083, China )
WANG Fei 2yu (Faculty of Resources and I nf ormation , China Universit y of Pet roleum , B ei j ing 102249, China )
K ONG Fan 2zhi (Research I nstitute of Pet roleum Ex ploration and Development , CN PC, B ei j ing 100083, China )
XI AO Zhong 2yao (Tarim Oil f iel d Com pany , Pet roChina, Tarim 841000, X inj iang , China )
CHE N Kai 2yuan (Faculty of Energy Resources , China University of Geosciences , B ei j ing 100083, China )
Abstract :Many newly found oils in Kuqa Dep ression were from J 2q source rocks , but t hey were not clearly recognized , especially t he type of organic matter was not well known 1A pyrolysis data base of Kuqa Basin was established to st udy t he characteristics of J 2q source rocks , J 2q lake facies source rocks were mainly developed from t he lower st rata , it was more developed in t he west t han t hat in t he nort h 1Organic abundance was higher and it s hydrocarbon genetic potential was t he highest among t he source rocks 1Type of organic matter was I ～II kerogen , which was t he best among t he source rocks 1Organic mat urity in t he west is higher t han t hat in t he nort h , it is at mat ure stage 1J 2q Forma 2tion is t he mo st important source rock in Kuqa Dep ression
K ey w ords :Kuqa Depression ; J 2q Formatio n ; organic abundance ; organic mat urity ; organic matter type
43Characteristics of H eavy Mineral Source Analysis in the 1st Member of T aizhou Formation in Subei B asin
X U T ian 2wu , WANG Y ing 2min , ZE NG Jian 2hui (MO E Key L aboratory of Oil and Gas A ccumulation Mechanism ; B asin and Reservoi r Research Center in China University of Pet roleum , B ei j ing 102249, China )
LI N Shu 2long (S huguang Oil Production Pl ant , L iaohe Oil f iel d Com pany , CN PC, Panj in 124109, L iaoning , China )
WANG Wen 2jun (Geoscience I nstitute of J iangsu Oil f iel d Com pany , S I N O P EC, Yangz hou 225000, J iangsu , China )
Abstract :There were some debates on t he directions of paleocurrent and sources in t he 1st member of Taizhou Formation of Subei Basin , t he characters of heavy minerals were analyzed by correlation a 2nalysis and R factor analysis , modes of 3different mineral compositions were identified and corre 2sponding parent rock types were also determined 1In combination wit h t he characteristics of conglom 2erate t hickness , and ratio of it s t hickness and formation t hickness f rom more t han 70wells , it is pointed out t hat t he major deposit s in t he 1st member of Taizhou Formation are f rom L usu uplift in west and Tongyang uplift in t he sout h of t he basin , t he second source is f rom Jianhu uplift , it is also pointed out t hat t he source f rom L usu uplift has t he biggest affect on Subei Basin 1
K ey w ords :Subei Basin ; Taizhou Formation ; heavy mineral ; conglomerate ; source area
49Hierarchical Boundary Characterization of Delta Front Mouth B ar R eservoir Architecture
LI Y un 2hai , WU Sheng 2he , LI Y an 2ping (Faculty of Resources and I nf orm ation , China University of Pet roleum , B ei j ing 102249, China ) CHE NG Hui 2ming , XI N Zhi 2guo (Geological S cienti f ic Research I nstitute of S hengli Oil f iel d , S I N O P EC, Dongy ing 257015, S handong , China )
ZH AO H ong 2bing , CUI Wen 2fu (S hengli Oil Production Pl ant of S hengli Oil f iel d , S I N O P EC, Dongy ing 257051, S handong , China )
Abstract :Based on high sequence st ratigrap hy and reservoir struct ural t heory , boundary of delta front mout h bar reservoir architect ure was hierarchically characterized 1The 8th sand group of second mem 2ber of Shahejie Formation in Block 2of Shengt uo Oilfield was subdivided into 3middle 2term base lev 2els and 17short 2term base levels by using high f requency lake overflow surfaces 1Wit hin t he isochrone st ratigrap hic f ramework , five level architect ural boundary systems of lacust rine mout h bar reservoir were established , which was crucial to oilfield develop ment at high water 2cut stage 1Five and four lev 2el bounding surfaces often acted as fluid 2flow barriers , while t hree level bounding surface was com 2posed of low permeability and t hick silt rocks 1The 3～5level architect ural dist ribution pat 2terns were modeled by using t he data f rom infill well pattern area 1of mout h bar reservoir indicates internal boundary cont rols on t he oil after waterflooding , which provides guideline for tapping t of K ey w ords :mout h bar ; architect ure ; boundary ; analysis ; fluid flow barrier ;Shengt uo Oilfield
62G enesis and Identif P in Fresh 2w ater R eservoirs
CHE NG X iang 2zhi (I in China University of Pet roleum , Dongy ing 257061, S handong , China )
ZHOU Can 2Pet Ex ploration and Development , Pet roChina, B ei j ing 100083, China )
FAN Y i 2ren of Geo 2and I nf orm ation in China Universit y of Pet roleum , Dongy ing 257061, S handong , China )
WANG Zhao 2(X Oil Production Plant , S hengli Oil f iel d , S I N O P EC, Dongy ing 257068, S handong , China )
H UANG Shu 2xian (Research I nstitute of Pet roleum Ex ploration and Development , Pet roChina, B ei j ing 100083, China )
Abstract :The genesis of low 2co nt rast pay zones was complex and various , t he low 2cont rast pay zones in f resh 2water reservoirs were divided into five categories 1Cro ss 2plot , new log technology , t raditio n 2al log data were effectively analyzed for recognizing t he different low 2cont rast pay zones , low 2cont rast pay zones were quantitatively evaluated by reaso nably selecting t he shaly sand sat uration model 1The integral qualitative recognition and quantitative interp retatio n in t he evaluation of low 2cont rast pay 2zones achieve a good effect in application , t he idea of low 2co nt rast pay zone evaluation in fresh 2water reservoir is established , it provides an economical , practical and reliable technique for evaluating low 2cont rast pay zones 1
K ey w ords :f resh 2water reservoir ; low cont rast pay zone ; genetic classification ; spontaneous poten 2tial ; new logging technique ; pay zone identification
66Characteristics and Interpretation of G as Logging Data in Subei B asin
XI AO Qiu 2sheng (Ex ploration Department of J iangsu Oil f iel d Com pany , S I N O P EC, Yangz hou 225009, J iangsu , China )
Abstract :Based on statistical analysis result s of gas logging data from past 30years in Subei Basin , t he basic characteristics of gas logging in different reservoirs and t he evaluation criteria for oil , gas and water layers were analyzed based on abnormal gas logging in different target zones of main pet ro 2liferous areas , such as Gaoyou Sag and Jinhu Sag of Subei Basin 1The result s show t hat gas logging is only related to fluid properties , not to lit hlogical feat ures of t he reservoirs 1For t he reservoirs wit h high and low resistivities , gas logging is a very important met hod for discovering and evaluating oil and gas layers and can effectively guide t he oil and gas exploration and develop ment 1Therefore , gas logging can compensate for ot her kind of logging 1
K ey w ords :gas logging ; whole hydrocarbon ; met hane ; rising times ; Subei Basin
69Deep B asin G as Seismic Characters and Prediction Methods
FE NG Quan 2xiong (School of Energy Resources , China University of Geosciences , B ei j ing 100083, China; Data Pro 2tech Corp 1L t d 1, CN OOC, Zhanj iang 524057, Guang dong , China )
H UANG Zhao 2lin (Energy I nvestment Corp 1L t d 1of CN OOC , B ei j ing 100016, China )
X UE Hui , X U Bo (School of Energy Resources , China University of Geosciences , B ei j ing 100083, China )
WANG Huan (Production Technical S ervice Tepu Hi gh 2tech Corp 1L t d 1, CN OOC, Zhanj iang 524057, Guangdong , China )
Abstract :On t he basis of analyzing geologic characters of deep 2basin gas , t he characters and predic 2tion met hods of seismic response were st udied and discussed 1Based on t he speciality of deep 2basin gas geologic characters , it was considered t hat t he seismic characters of deep 2basin gas included “strong amplit ude in flat spot and low f requency ribbon , complex wave form and abnormal velocity ”1In allusio n to t he seismic response characters of deep 2basin gas , in combination wit h t he predicting techniques abroad and conventional gas recognition met hod , t he met hods for predicting deep 2basin gas wit h seismic technique are divided into 5categories (amplit ude , attenuation , wave form , velocity and co mp rehensive prediction ) involving 20types in total 1Systematical met hods are established for deep 2basin gas p redictio n 1Eight seismic prediction met hods wit h obvious effect and recognition effi 2
2007年12月 第29卷 第6期石油天然气学报(江汉石油学院学报)
Dec 12007 Vol 129 No 16Journal of Oil and G as T echnology (J 1J PI ) ・49・
三角洲前缘河口坝储层构型界面层次表征
李云海, 吴胜和, 李艳平 (中国石油大学(北京) 资源与信息学院, 北京102249)
程会明, 辛志国 (胜利油田有限公司地质科学研究院, 山东东营257015)
赵红兵, 崔文富 (胜利油田有限公司胜利采油厂, 山东东营)
[摘要]以高分辨率层序地层学和储层构型理论为指导, , 8砂组河
口坝砂体构型界面进行了层次表征。8、17个短期基
准面旋回。在等时地层格架内, :5级界面常发育稳定的前三角洲泥
岩, ; 4、粉砂质泥岩组成, 形成流体渗流屏障; 3级界
。利用密井网区的动态
。构型界面的层次表征揭示了储层内部复杂的构型界面对剩余
, 为剩余油的挖潜指明了方向。
[关键词]高分辨率层序地层学; 三角洲; 河口坝; 构型界面; 层次分析; 渗流屏障; 胜坨油田
[中图分类号]TE12113; TE19[文献标识码]A [文章编号]100029752(2007) 0620049204
构型是指沉积砂体内部由各级次沉积界面所限定的砂质单元和不连续“薄夹层”的几何形态、规模大小、相互排列方式与接触关系等结构特征。目前, 野外露头和现代沉积的构型研究已取得一定进展[1], 但地下储层的构型研究受资料所限, 仍在起步阶段[2,3]。构型应用于河流、风成和深水沉积物相模型中, 被认为是一个合理成熟的方法, 而三角洲沉积的构型分析研究不足。
沉积体的沉积界面等级概念及分级体系已广泛应用于储层沉积学研究领域中, 成为认识沉积体内部构型的一种有效方法。利用不同规模的界面, 可将地层分成一系列的三维沉积单元, 既有利于分类描述, 也有利于研究各级沉积作用的规模和持续时间[4]。笔者依据构型理论和层次分析方法, 对胜二区沙二段8砂组河口坝储层构型界面进行层次表征, 建立储层内部构型界面分布模型, 为河口坝储层非均质性研究和剩余油挖潜提供方向。
1 高分辨率层序地层格架
胜坨油田位于济阳坳陷东营凹陷北部, 陈家庄凸起南端, 是一个逆牵引背斜构造油田。主要断层将胜坨油田分割成胜一区、胜二区和胜三区3个区, 其中胜二区位于胜坨油田中部, 是一个北部和东部被断层切割、西南部与边水相连的扇形断块油藏。沙二段是主力含油层系, 共分为15个砂层组。详细的沉积环境研究表明, 沙二段时期发育河控湖相三角洲沉积, 其中沙二段8砂组砂体是典型的三角洲前缘沉积, 以发育厚层的河口坝砂体为特征。沉积微相的研究成果大量被国内外专著引用, 但储层构型的研究尚很少[5]。高含水开发后期, 常规的沉积微相研究已不能满足胜二区沙二段8砂组剩余油挖潜的需要, 必须精细研究储层内部构型特征, 揭示储层内部小尺度的非均质性。
通过大量的单井和连井剖面精细分析和对比, 采用以高频沉积旋回对应的湖泛面为界划分高精度层序地层单元的分析方法, 在沙二段8砂组识别出3个中期基准面旋回、17个短期基准面旋回。中期基准面旋回均为基准面下降的不对称半旋回, 对应于3个水体向上变浅的过程。短期基准面旋回的划分与井间对比充分考虑了三角洲前缘沉积的斜坡(clinoform ) 特点, 以斜坡的空间发育特点为参考, 追踪 [收稿日期]2007208210
[基金项目]中国石油化工集团公司重大科技攻关项目(P01035) 。
河口坝的顶面。以高分辨率层序地层学划分结果为依据, 将沙二段8砂组地层细分为3个小层和17个韵律层。三角洲前缘河口坝在空间上具有向盆地前积、不同时期河口坝垂向叠加、侧向相连的特点, 所以每个韵律层的发育范围有限, 单井在每个小层平均钻遇3～5个韵律层不等。
2 构型界面层次分析
211 层次界面分级
岩心上构型界面级次的识别、划分, 键[6]。为了进一步揭示沉积体内部沉积层次, 对沙二段8划分, 从小到大共划分出如下5级界面(图1)
。
图1 三角洲前缘河口坝砂体层次界面分级
1) 1级界面 为交错层系的界面, 即由一系列相同纹层组成的界面, 界面的方向与古水流的方向有关。其特点是没有明显的侵蚀作用, 侧向上可被更高级次界面截蚀。在8砂组储层中, 主要表现为低角度斜层理层系界面、板状交错层理层系界面、平行层理层系界面和波状交错层理层系界面等。
2) 2级界面 为层系组界面, 反映流动条件或流动方向的变化, 是砂体内部不同岩相之间的分界面, 在侧向上可被更高级界面削蚀。界面方向与古水流的变化有关, 且河口坝砂体不同部位的界面方向也不同。与1级界面的区别是界面上下的岩相发生变化。
3) 3级界面 为单一河口坝砂体内部增生体的顶、底界面, 界面向湖心方向倾斜, 其上披覆着短暂间洪期沉积的薄泥质夹层, 薄泥层界面上下的岩相组合相似。此类界面反映了河口沉积作用的短暂变化, 如河水流量的变化、负载的增减或湖水的季节性涨缩等。
4) 4级界面 为多个河口坝增生体叠合形成的单一河口坝的顶界面, 界面亦向湖心方向倾斜, 是三角洲朵体废弃后, 水体加深的间湾沉积形成。4级界面是8砂组三角洲前缘河口坝沉积的各韵律层分界面, 界面上下的岩相明显不同。界面横向延伸长度较大, 基本覆盖下伏的单一河口坝砂体, 顶部可以被更高级界面削蚀, 底部常可与三级界面重合或合并。
5) 5级界面 为多个单一河口坝垂向叠加与侧向叠合形成的河口坝复合体的顶界面, 是8砂组三角洲前缘沉积体中识别出来的最高级别的沉积界面, 为主要的侵蚀或洪泛面。界面向湖心方向倾斜, 多为平坦或略微波状起伏, 延伸范围广, 分布稳定, 覆盖整个研究区, 由三角洲朵体的迁移或水下分流河
由上述可知, 5级界面限定整个研究区, 是主要的侵蚀或洪泛面; 4级界面通常定义单一河口坝坝体; 3级界面分隔三角洲前缘河口坝层序内部的增生体; 1～2级界面只在岩心中可识别, 常规测井资料无法识别, 因此不做进一步研究。界面的级别在空间上可能发生侧向渐变, 任何级别的界面都可能被同级别或更高级别的界面削截, 但不会被更低级别的界面削截。
212 构型界面识别
不同层次的构型界面上下均分布着细粒的沉积, 如粉砂质泥岩、泥岩或成岩作用形成的钙质砂岩, 形成隔夹层, 隔夹层对流体渗流及原油采收率的影响很大, 是储层内部非均质性的主要地质因素, 同时也是识别构型界面的关键。
按照构型研究的层次性原则, 对应于3～5级层次界面, 共分为3级隔夹层。Ⅰ级为单一河口坝增生体之间的夹层, , 014m , 自然电位(SP ) 与自然伽马(GR ) 曲线轻微回返, 夹层侧向延伸范围有限, 局部可被后期洪水冲蚀而未保存, , ; Ⅱ级为单, , 物性较差, 可对流体渗流起屏障作用, 厚度012～110m , 曲线幅度差中等; Ⅲ级为河口坝复合体之间的厚层前三角洲泥质层, SP , ML 曲线无幅度差, 延伸范围广, 不具渗透性, 是有效的隔层。
通过取心井岩电标定, 在未取
心井中识别出各级次隔夹层, 进而
在单井中划分出3～5级构型界面。
213 构型界面的开发响应
对于沙二段8砂组而言, 3～4
级界面对于开发后期的意义更重要,
因为3～4级界面是层内剩余油的主
要控制因素, 纵向剩余油的分布与平
面剩余油的富集均与3～4级界面相
关。利用研究区密井网的动态监测资
料, 可揭示构型界面的存在, 分析构
型界面控制的剩余油分布。
1) 重复地层测试RFT 2003年
1月2日1X174井RFT 压力测试成果
揭示了4级界面对储层的分隔性(图
2) 。211410m 附近为一个4级构型界图2 1X 174井RFT 测试成果图
面, 分隔815与816韵律层, 界面处
的岩性为泥岩与粉砂质泥岩, 厚度约
112m 。构型界面之下的薄层低渗透远
砂坝砂体地层压力低于界面之上的厚图3 22188井吸水剖面成果图
层高渗透河口坝主体地层压力, 说明
此处4级构型界面对地下流体的渗流起主要控制作用, 将储层分割为两个独立的流动单元, 下部的远砂坝砂体动用程度高于上部的河口坝主体。据此分析, 河口坝主体仍有剩余油分布。
2) 吸水剖面 1998年7月4日22188井吸水剖面揭示3级界面影响剩余油分布(图3) 。832韵律层内部存在一个低渗透的3级构型界面(217114m ) , 界面上下吸水状况差异很大, 上部河口坝砂体渗透率级差小, 注入水在重力作用下, 易下沉至构型界面之上; 下部河口坝砂体渗透率级差大, 重力作用不明显, 注入水优先沿顶部高渗透砂体流动, 即在构型界面之下流动, 造成构型界面上下吸水强度大, 剩余油相对不富集。
・52・ 石油天然气学报(江汉石油学院学报) 2007年12月3 构型界面层次建模
构型界面层次建模的关键是井间预测问题。沙二段8
砂组的密井网检查井区有丰富的静态与动态资料, 为构
型界面的井间预测和层次建模提供了保障。由于3级与4
～5级构型界面的分布特点不同, 分2个层次建立构型界
面模型。先建立4级/5级构型界面三维模型, 在此模型
限制下, 选择资料丰富的井组, 的构型界面展布, 建立3级构型界面的剖面模型。
4级/5级构型界面的分布范围广, 层易于识别, , 图4 81小层4级/5级界面三维空间分布模型, 采
(图4) 。4级/5级构型界面模型反映81小层沉积时期, 砂体, 同时, 亦向西北方向迁移。4级构型界面限定的砂体呈透镜状。
根据22188井示踪剂监测结果推断韵律层内部3级构型界面的分布, 建立了示踪剂监测井组的3级构型界面剖面模型(图5) 。由于3级界面存在和钙质夹层的遮挡, 2
2188井注入的示踪剂未在32197和32199井检测出。3级界面的延伸范围有限, 泥质夹层的发育不均匀, 依据地下资料进行井间预测难度很大, 目前还不能在全区范围内建立模型。
图5 83小层3级界面剖面分布模型
4 结 论
1) 5级界面构成小层间的隔层, 4级界面作为渗流屏障, 将单一河口坝分割成相对独立的流动单元, 3级界面对流体渗流具有遮挡与缓冲作用。3级与4级界面伴生的泥质或泥质与钙质夹层组合体对剩余油的分布起决定作用。
2) 通过实例分析说明, 表面并不复杂的成熟油田仍具有进一步挖潜的机遇。构型界面分析是识别储层非均质性的有效方法。
[参考文献]
[1]王振奇, 何贞铭, 张昌民等1三角洲前缘露头储层层次分析———以鄂尔多斯盆地东缘潭家河剖面为例[J]1江汉石油学院学报,
2004, 26(3) :32～351
[2]李阳1我国油藏开发地质研究进展[J]1石油学报, 2007, 28(3) :75～791
[3]刘自亮1辫状河三角洲前缘厚层储集砂体沉积学研究[D ]1兰州:中国科学院研究生院(兰州地质研究所) , 20041
[4]王俊玲, 任纪舜1嫩江现代河流沉积体岩相及内部构形要素分析[J]1地质科学, 2001, 36(4) :385～3941
[5]何文祥, 吴胜和, 唐义疆等1河口坝砂体构型精细解剖[J]1石油勘探与开发, 2005, 32(5) :42～461
[6]马世忠, 王一博, 崔义等1油气区水下分流河道内部建筑结构模式的建立[J]1大庆石油学院学报, 2006, 30(5) :1～31
According to t he analysis above , it is concluded t hat t here are t hree areas for secondary oil explora 2tion , it is very hopef ul to find some geological reserves and it is of great significance for imp roving oilfield p roduction outp ut and reserves 1
K ey w ords :Biyang Dep ression ; nort hern slope ; oil and gas ; enrichment rules ; secondary exploration 33V olcanic Logging R ecognition in R eservoir Analysis
Y ANG Shen 2gu (Faculty of Resources , China University of Geosciences , W uhan 430074, Hubei , China; College of Geosciences , Yangtze University , J ingz hou 434023, Hubei , China )
LI U X iao 2cui (N o 12Oil Production Plant , Zhongy uan Oil f iel d Com pany , S I N O P EC, Puy ang 457532, Henan, China )
(H U Zhi 2hua College of Geosciences , Yangtze University , J ingz hou 434023, H ubei , China )
FAN Zhen , X U Jiang 2tao , CAO Zuo (X inj iang Oil f iel d Com pany , CN PC, Karam ay 834000, X inj iang , China Abstract :In t he process of volcanic oil and gas , objective rea 2sons , t here existed insufficient lit hologic , which con 2st rained t heir exploration and develop ment 1On t of volcanic rocks was simplified for reservoir analysis , of simplified volcanic types used in co nventional logging It t hat t he types of conventional logging curves wit h better , DEN , R T (RXO , RS , COND ) , GR and CAL 1Generally t presented high gamma ray , while volcanic clastic rocks and lava p , high density and low interval t ransit time 1In lava zones , logging curve p lava break , it reflected high interval transit time and low density and low 1By integrating data from oilfields , chart board and criterion are established for logging recognition 1The analytical met hod , idea and chart board are of great significance for t he basic st udy of volcanic reservoirs 1
K ey w ords :volcanic rock ; oil and gas pool ; reservoir ; lit hologic recognition ; logging data
38Characteristics of J 2q Source R ocks in K uqa Depression
LI Qian (Faculty of Energy Resources , China Universit y of Geosciences , B ei j ing 100083, China )
WANG Fei 2yu (Faculty of Resources and I nf ormation , China Universit y of Pet roleum , B ei j ing 102249, China )
K ONG Fan 2zhi (Research I nstitute of Pet roleum Ex ploration and Development , CN PC, B ei j ing 100083, China )
XI AO Zhong 2yao (Tarim Oil f iel d Com pany , Pet roChina, Tarim 841000, X inj iang , China )
CHE N Kai 2yuan (Faculty of Energy Resources , China University of Geosciences , B ei j ing 100083, China )
Abstract :Many newly found oils in Kuqa Dep ression were from J 2q source rocks , but t hey were not clearly recognized , especially t he type of organic matter was not well known 1A pyrolysis data base of Kuqa Basin was established to st udy t he characteristics of J 2q source rocks , J 2q lake facies source rocks were mainly developed from t he lower st rata , it was more developed in t he west t han t hat in t he nort h 1Organic abundance was higher and it s hydrocarbon genetic potential was t he highest among t he source rocks 1Type of organic matter was I ～II kerogen , which was t he best among t he source rocks 1Organic mat urity in t he west is higher t han t hat in t he nort h , it is at mat ure stage 1J 2q Forma 2tion is t he mo st important source rock in Kuqa Dep ression
K ey w ords :Kuqa Depression ; J 2q Formatio n ; organic abundance ; organic mat urity ; organic matter type
43Characteristics of H eavy Mineral Source Analysis in the 1st Member of T aizhou Formation in Subei B asin
X U T ian 2wu , WANG Y ing 2min , ZE NG Jian 2hui (MO E Key L aboratory of Oil and Gas A ccumulation Mechanism ; B asin and Reservoi r Research Center in China University of Pet roleum , B ei j ing 102249, China )
LI N Shu 2long (S huguang Oil Production Pl ant , L iaohe Oil f iel d Com pany , CN PC, Panj in 124109, L iaoning , China )
WANG Wen 2jun (Geoscience I nstitute of J iangsu Oil f iel d Com pany , S I N O P EC, Yangz hou 225000, J iangsu , China )
Abstract :There were some debates on t he directions of paleocurrent and sources in t he 1st member of Taizhou Formation of Subei Basin , t he characters of heavy minerals were analyzed by correlation a 2nalysis and R factor analysis , modes of 3different mineral compositions were identified and corre 2sponding parent rock types were also determined 1In combination wit h t he characteristics of conglom 2erate t hickness , and ratio of it s t hickness and formation t hickness f rom more t han 70wells , it is pointed out t hat t he major deposit s in t he 1st member of Taizhou Formation are f rom L usu uplift in west and Tongyang uplift in t he sout h of t he basin , t he second source is f rom Jianhu uplift , it is also pointed out t hat t he source f rom L usu uplift has t he biggest affect on Subei Basin 1
K ey w ords :Subei Basin ; Taizhou Formation ; heavy mineral ; conglomerate ; source area
49Hierarchical Boundary Characterization of Delta Front Mouth B ar R eservoir Architecture
LI Y un 2hai , WU Sheng 2he , LI Y an 2ping (Faculty of Resources and I nf orm ation , China University of Pet roleum , B ei j ing 102249, China ) CHE NG Hui 2ming , XI N Zhi 2guo (Geological S cienti f ic Research I nstitute of S hengli Oil f iel d , S I N O P EC, Dongy ing 257015, S handong , China )
ZH AO H ong 2bing , CUI Wen 2fu (S hengli Oil Production Pl ant of S hengli Oil f iel d , S I N O P EC, Dongy ing 257051, S handong , China )
Abstract :Based on high sequence st ratigrap hy and reservoir struct ural t heory , boundary of delta front mout h bar reservoir architect ure was hierarchically characterized 1The 8th sand group of second mem 2ber of Shahejie Formation in Block 2of Shengt uo Oilfield was subdivided into 3middle 2term base lev 2els and 17short 2term base levels by using high f requency lake overflow surfaces 1Wit hin t he isochrone st ratigrap hic f ramework , five level architect ural boundary systems of lacust rine mout h bar reservoir were established , which was crucial to oilfield develop ment at high water 2cut stage 1Five and four lev 2el bounding surfaces often acted as fluid 2flow barriers , while t hree level bounding surface was com 2posed of low permeability and t hick silt rocks 1The 3～5level architect ural dist ribution pat 2terns were modeled by using t he data f rom infill well pattern area 1of mout h bar reservoir indicates internal boundary cont rols on t he oil after waterflooding , which provides guideline for tapping t of K ey w ords :mout h bar ; architect ure ; boundary ; analysis ; fluid flow barrier ;Shengt uo Oilfield
62G enesis and Identif P in Fresh 2w ater R eservoirs
CHE NG X iang 2zhi (I in China University of Pet roleum , Dongy ing 257061, S handong , China )
ZHOU Can 2Pet Ex ploration and Development , Pet roChina, B ei j ing 100083, China )
FAN Y i 2ren of Geo 2and I nf orm ation in China Universit y of Pet roleum , Dongy ing 257061, S handong , China )
WANG Zhao 2(X Oil Production Plant , S hengli Oil f iel d , S I N O P EC, Dongy ing 257068, S handong , China )
H UANG Shu 2xian (Research I nstitute of Pet roleum Ex ploration and Development , Pet roChina, B ei j ing 100083, China )
Abstract :The genesis of low 2co nt rast pay zones was complex and various , t he low 2cont rast pay zones in f resh 2water reservoirs were divided into five categories 1Cro ss 2plot , new log technology , t raditio n 2al log data were effectively analyzed for recognizing t he different low 2cont rast pay zones , low 2cont rast pay zones were quantitatively evaluated by reaso nably selecting t he shaly sand sat uration model 1The integral qualitative recognition and quantitative interp retatio n in t he evaluation of low 2cont rast pay 2zones achieve a good effect in application , t he idea of low 2co nt rast pay zone evaluation in fresh 2water reservoir is established , it provides an economical , practical and reliable technique for evaluating low 2cont rast pay zones 1
K ey w ords :f resh 2water reservoir ; low cont rast pay zone ; genetic classification ; spontaneous poten 2tial ; new logging technique ; pay zone identification
66Characteristics and Interpretation of G as Logging Data in Subei B asin
XI AO Qiu 2sheng (Ex ploration Department of J iangsu Oil f iel d Com pany , S I N O P EC, Yangz hou 225009, J iangsu , China )
Abstract :Based on statistical analysis result s of gas logging data from past 30years in Subei Basin , t he basic characteristics of gas logging in different reservoirs and t he evaluation criteria for oil , gas and water layers were analyzed based on abnormal gas logging in different target zones of main pet ro 2liferous areas , such as Gaoyou Sag and Jinhu Sag of Subei Basin 1The result s show t hat gas logging is only related to fluid properties , not to lit hlogical feat ures of t he reservoirs 1For t he reservoirs wit h high and low resistivities , gas logging is a very important met hod for discovering and evaluating oil and gas layers and can effectively guide t he oil and gas exploration and develop ment 1Therefore , gas logging can compensate for ot her kind of logging 1
K ey w ords :gas logging ; whole hydrocarbon ; met hane ; rising times ; Subei Basin
69Deep B asin G as Seismic Characters and Prediction Methods
FE NG Quan 2xiong (School of Energy Resources , China University of Geosciences , B ei j ing 100083, China; Data Pro 2tech Corp 1L t d 1, CN OOC, Zhanj iang 524057, Guang dong , China )
H UANG Zhao 2lin (Energy I nvestment Corp 1L t d 1of CN OOC , B ei j ing 100016, China )
X UE Hui , X U Bo (School of Energy Resources , China University of Geosciences , B ei j ing 100083, China )
WANG Huan (Production Technical S ervice Tepu Hi gh 2tech Corp 1L t d 1, CN OOC, Zhanj iang 524057, Guangdong , China )
Abstract :On t he basis of analyzing geologic characters of deep 2basin gas , t he characters and predic 2tion met hods of seismic response were st udied and discussed 1Based on t he speciality of deep 2basin gas geologic characters , it was considered t hat t he seismic characters of deep 2basin gas included “strong amplit ude in flat spot and low f requency ribbon , complex wave form and abnormal velocity ”1In allusio n to t he seismic response characters of deep 2basin gas , in combination wit h t he predicting techniques abroad and conventional gas recognition met hod , t he met hods for predicting deep 2basin gas wit h seismic technique are divided into 5categories (amplit ude , attenuation , wave form , velocity and co mp rehensive prediction ) involving 20types in total 1Systematical met hods are established for deep 2basin gas p redictio n 1Eight seismic prediction met hods wit h obvious effect and recognition effi 2