石油天然气学报(江汉石油学院学报) 2010年12月 第32卷 第6期
2010 Vol 32 No 6Journal of Oil and Gas Technology (J JPI) Dec
27
苏北 南黄海盆地的构造演化分析
刘东鹰
(中石化江苏油田分公司地质科学研究院, 江苏扬州225009)
[摘要]通过苏北 南黄海盆地的拉张率和沉降率等的分析认为, 苏北 南黄海盆地的构造演化主要分为3个阶段。K 2t E 1f 沉积时期是苏北 南黄海盆地发育的兴盛期, 这一时期盆地的拉张率最大, 沉积速率也最大, 吴堡运动剥蚀强度具有东强西弱的特点。E 2d E 2s 沉积时期为典型断陷盆地发育期, 这一时期的盆地的拉张率和沉降率一般都小于前一时期。三垛运动使得凹陷保存地层较全, 凸起、斜坡保存地层较少; 南坳地层剥蚀少, 北坳地层剥蚀多; 三垛运动后, 盆地由断陷转为拗陷, 早期分割的断陷沉积转为统一的拗陷沉积。
[关键词]拉张率分析; 沉降率分析; 构造演化; 苏北 南黄海盆地[中图分类号]T E121 2
[文献标识码]A
[文章编号]1000 9752(2010) 06 0027 05
苏北 南黄海盆地是发育在扬子板块下扬子区构造形变极为复杂的中古生界基底之上的中新生界陆相盆地, 是由晚白垩世和新生代地层构成的沉积盆地。晚白垩世和新生代的沉积盖层可以分为泰州组(K 2t) 、阜宁组(E 1f) 、戴南组(E 2d) 、三垛组(E 2s) 、盐城组(N 2y) 、东台组(Qd) 等。包含有4个主要不整合, 即:盆地基底不整合面(K 2t 、E 1f 与下伏地层之间的不整合面) 、E 2d 与下伏地层之间的不整合面、E 2s 与下伏地层之间的不整合面、N 2y 与下伏地层之间的不整合面, 这4个不整合面的构造运动分别命名为仪征运动、吴堡运动、真武运动和三垛运动。许多学者对苏北 南黄海盆地的构造演化和形成机制进行了研究, 存在不同的观点和结论论盆地的构造演化和各时期盆地的性质。
[1~7]
。笔者通过对盆地的拉张率和沉降率等的分析, 讨
1 盆地拉张率分析
根据苏北 南黄海盆地的10余条地震解释剖面计算(表1) 认为, 虽然在不同凹陷、不同时期的拉
表1 苏北 南黄海盆地主要凹陷拉张率
凹陷及测线
洪泽凹陷
金湖凹陷
xus 1270Sg38 5M Q42小计G44G78G78H N117 5小计NY8346线46线
拉张率/%
K 2t E 1f 112 19 35 47 78 75 63 85 64 67 07 312 2
E 1f 2 E 1f 4
8 37 38 57 812 115 34 95 85 36 314 0
E 2d
5 51 26 33 311 73 77 64 46 02 417 017 0
E 2s
12 56 36 76 48 24 03 77 15 53 414 38 5
高邮凹陷
溱潼凹陷海安凹陷
盐城凹陷
南黄海南部南四凹南黄海南部南五凹
注:表中xu s1270、Sg38 5、M Q42 为地震测线号。
[收稿日期]2010 09 14
[基金项目]国家科技重大专项(2008ZX05005 003 005) 。
[作者简介]刘东鹰(1961 ) , 男, 1982年华东石油学院毕业, 博士, 高级工程师, 现主要从事石油地质勘探工作。
张率存在差异, 但具有一定的规律性。
从凹陷间拉张率的变化分析, 泰州组 阜一段(K 2t E 1f 1) 沉积时期, 西部的洪泽、金湖凹陷和中部的高邮凹陷、南黄海南部的南五凹拉张率相对较大, 分别为12 1%、7 7%、8 7%、12 2%。阜二段 阜四段(E 1f 2 E 1f 4) 沉积时期, 中部的高邮、溱潼凹陷、南黄海南部的南五凹较大, 分别为12 1%、15 3%、14 0%。E 2d 沉积时期, 拉张率最大的凹陷转移到东部南黄海南部盆地的南四凹、南五凹, 都为17%; 同时中部的高邮凹陷保持较大的拉张率, 为11 7%。E 2s 沉积时期, 拉张率较大的分布在盆地的东西两端, 分别为西部的洪泽凹陷和东部的南四凹、南五凹, 拉张率分别为12 5%、14 3%和8 5%。总之, 除高邮凹陷一直保持较大的拉张率之外, 拉张率大的凹陷从K 2t E 1f 1沉积时期至E 2d 沉积时期由西部向东部转移, 至E 2s 沉积时期转移到盆地两端; 从沉积的时间序列分析, 拉张率的变化大体存在两个阶段。K 2t E 1f 4沉积时期, 除洪泽凹陷、盐城凹陷外, 其他各凹陷拉张率逐步增加。E 2d 沉积时期, 除高邮凹陷、海安凹陷、南四凹、南五凹外, 其他各凹陷拉张率降至最低。
2 盆地沉降率分析
从苏北盆地各凹陷沉降率对比分析可知(表2) , 沉降史可分为3个阶段, K 2t E 1f 4沉积阶段, 沉降率为慢! 快! 慢! 快两个旋回; E 1f 2、E 1f 4沉积阶段沉降率较大, 其中E 1f 4沉积阶段在各个阶段中沉降率最大。虽然各凹陷沉降率差别较大, 但总体上是西部和中部各凹陷大于东部各凹陷。E 2d E 2s 沉积阶段, 沉降率为慢! 快! 慢的完整旋回, 西部和中部各凹陷的沉降率明显大于东部各凹陷。E 2y Qd 沉积阶段, 为慢! 快的正旋回, 各凹陷沉降率的关系与前两个阶段相反, 东部各凹陷明显大于西部和中部各凹陷。从各个阶段对比来看, K 2t E 1f 4沉积阶段的沉降率在各阶段中最大, 是盆地快速沉降期。
表2 苏北盆地各凹陷沉降率
层位K 2t E 1f 1E 1f 2E 1f 3E 1f 4E 2d 1E 2d 2E 2s 1E 2s 2E 2y 1E 2y 2Qd
沉降率/m M a -1
金湖15445532 5101 2457570 562 56 5830
高邮5 835 590
5515545 545655515 527 539 5
溱潼5 73590 5
20194 [1**********] 53549 5
海安52065 5
31152 510 57 5555232 538114 5
102048 53017 54582 5白驹103055 5
盐城10 53057 5
55122 519 51565 54015 52555 5
苏北盆地各时期的沉降率与拉张率有一定的正相关关系。时间序列比较, K 2t E 1f 沉积阶段, 拉张率大、沉降率也相对较大, E 2d 、E 2s 沉积阶段拉张率较小、沉降率也较小; 各凹陷间对比, 高邮凹陷
总体拉张率大、沉降率也大, 金湖、盐城凹陷总体拉张率小、沉降率也小。表明地层的沉降受断裂拉开速率的控制。
南黄海盆地的沉降率与苏北盆地极为类似[8](表3) , K 2t E 1f 沉积阶段为快速沉降期, 南坳最大达137m /M a, 北坳最大达138m/M a 。E 2d E 2s 沉积阶段, 沉降率基本为慢! 快的正旋回。E 2y Qd 沉积阶段, 也为慢! 快的正旋回。表明期构造演化史与苏北盆地类似。
表3 南黄海盆地各时期沉降率
构造单元K 2t E 1f 1E 1f 2E 1f 3E 1f 4E 2d E 2s 1E 2s 2E 2y 1E 2y 2Qd
南坳
地层厚度/m
24148367 5332 5508 526196 5402 5666 5815 5344
压实率0 310 31
0 360 360 360 430 430 430 650 81
沉降率/m M a -12 615
[***********]3
1
北坳
地层厚度/m
574439 [**************]1剥蚀389637257 5
0 650 81
294747
压实率0 310 31
0 360 360 360 430 43
沉降率/m M a -1
30138
[1**********]8
3 苏北 南黄海盆地构造演化
由于受扬子板块与华北板块碰撞和古太平洋板块的右旋挤压的作用, 中生代中国大陆的地形总体为东高西低的特征。这一时期苏北 南黄海盆地区总体海拔高度在2000m 以上。晚白垩世以来, 由于太平洋板块的高角度俯冲, 中国东部虽然转换为伸展拉张环境, 但地形、地貌仍然继承早期的特征, 浦口组、赤山组的沉积呈现出高原湖泊、高原沙漠特点。仪征运动虽然对早期的地层进行了剥蚀改造, 但从前K 2t 残留的地层分布看(图1) , 仍是东老西新、南老北新, 推测苏北 南黄海盆地区的地形为东高西低、南高北低。但由于江南古陆的存在, 盆地西南部也存在物源区。苏
北 南黄海盆地形成于晚白垩世仪征运动。盆地是在继承早期的地形、地貌特征的基础上, 在持续拉张环境下发生、发育起来的。3 1 盆地发育的兴盛期
K 2t E 1f 沉积时期是苏北 南黄海盆地发育的兴盛期, 这一时期盆地的拉张率最大, 沉积速率也最大。与全球海平面的升降相对应, 湖盆也经历3次水体上升的过程, 形成了3个正旋回沉积:K 2t 正旋回、E 1f 1 E 1f 2正旋回和E 1f 3 E 1f 4正旋回。各旋回的上部均受过海侵的影响, 以半深湖 深湖相暗色泥岩沉积为主, 构成主要生油岩系。旋回下部为河流 三角洲、扇三角洲体系, 具有较好的储集条件。强烈的拉张和深陷, 以及水体大幅上升(海侵) 的叠加效应, 使K 2t E 1f 地层的厚度受边界断层控制, 呈现出∀箕状#凹陷的特点, E 1f 2∀七尖峰#稳定标志层段的厚度变化是这一特征的有力表述。沉
[9]
[8]
图1 前K 2t 残留地层分布推断图
30
石油天然气学报(江汉石油学院学报) 2010年12月
积相的变化却显示了∀坳陷#沉积的特点。说明K 2t 、E 1f 2、E 1f 4沉积时期湖盆面积迅速扩大, 水体大幅上升, 盆地中的凸起、凹陷均处于较深水环境, 凹陷的边界断层对沉积的控制作用仅表现为厚度变化, 而沉积相未受到明显影响。
E 1f 4沉积以后的吴堡运动使盆地抬升。伴随着全球海平面的下降, 湖盆中的水体也随之下降, 进而全部退出苏北 南黄海盆
地区, 沉积岩广泛暴露地
表, 遭受风化、剥蚀。受这一时期剥蚀强度有东强西弱的特点(图2) 。3 2 盆地典型断陷发育期
E 2d E 2s 沉积时期为典型断陷盆地发育期。水体再次进入盆地。E 2d 沉积时期, 由于水体范围小, 所以盆地具有较强的分割性。受边界断层控制, 地层厚度变化很大。沉积相特征为靠边界断层一侧为水下扇体系, 斜坡一侧为河流 三角洲体系。具有典型的箕状断陷盆地特征。E 2s 沉积时期水体扩大, 形成广泛的超覆, 从下部的河流、沼泽相沉积转变为上部的浅湖相沉积。
E 2s 沉积后的三垛运动, 是由于受印度板块与欧亚板块碰撞的影响, 盆地区从近东西向的拉张环境转变为近南北向的挤压环境, 盆地区整体抬升, 遭受长时间的剥蚀。从E 2s 地层保存状况分析(图3) , 凹陷保存地层较全, 凸起、斜坡保存地层较少; 南凹地层剥蚀少,
北凹地层剥蚀多。
[10, 11]
图2 前E 2d 残留地层分布图
图3 苏北 南黄海盆地E 2s 对比图
第32卷第6期刘东鹰:苏北 南黄海盆地的构造演化分析
31
3 3 盆地拗陷发育期
三垛运动后, 盆地由断陷转为拗陷, 早期分割的断陷沉积转为统一的拗陷沉积。断陷期形成的张性断裂, 除凹陷边界同生断裂活动到N 2y 1沉积时期外, 大部分在拗陷期停止活动。由于受印度板块的长期推挤作用, 盆地的西部抬升, 东部下沉, 沉降量由早期的∀西大东小#变为盐城期的∀东大西小#。同时在盆地东西两侧的少量早期正断层反转为逆断层。
4 结 论
1) 总体而言, K 2t E 1f 沉积时期的拉张率大于以后各沉积时期的拉张率。各凹陷在不同沉积时期的拉张率有一些变化, K 2t E 1f 1沉积时期, 西部和中部各凹陷拉张率相对较大; E 1f 2 E 1f 4沉积时期, 中部各凹陷较大; E 2d 沉积时期, 拉张率最大的凹陷转移到东部南黄海南部盆地的南四凹、南五凹, 同时中部的高邮凹陷保持较大的拉张率; E 2s 沉积时期, 拉张率较大的分布在盆地的东西两端。
2) 沉降史可分为3个阶段, 在各沉积时期中, E 1f 2、E 1f 4沉积阶段沉降率较大。沉降率与拉张率有一定的正相关关系。时间序列比较, K 2t E 1f 沉积阶段, 拉张率大、沉降率也相对较大; E 2d 、E 2s 沉积阶段拉张率较小、沉降率也较小。
3) 苏北 南黄海盆地的构造演化主要分为3个阶段。K 2t E 1f 沉积时期是苏北 南黄海盆地发育的兴盛期; E 2d E 2s 沉积时期为典型断陷盆地发育期, 这一时期的盆地的拉张率和沉积速率一般都小于前一时期; 三垛运动后, 盆地由断陷转为拗陷, 早期分割的断陷沉积转为统一的拗陷沉积。
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[编辑] 宋换新
ples or the s imilarity betw een th e phase variables, it w as classified s tep by step By taking W ellb lock Xi259in C heng hao Oilfield for exam ple, Q h ierarchical clustering m ethod of cluster analysis w as u sed to s tu dy the type of C32reservoir, and s am ples w ere class ified, by w h ich the law of spatial distribution of r eservoirs w as ob tained Th e r esults sh ow that th e m ethod for reservoir evaluation is feasible w ith high rationality
Key words :reservoir evaluation; clu ster analysis; Q type h ierarch ical clustering method; Chenghao Oilfield
27Analysis on Structural Evolution of Northern Jiangsu South Yellow Sea Basin
LIU Do ng y ing (Au thor s Ad d ress :Re search Institute of G eosc ienc es, J iangsu Oilf ie ld Company , SI N OP EC, Yang zh ou
225009, J iang su, China)
Abstract:By analysis of exten sion ratio and sub side ratio of northern Jiangsu S ou th Yellow S ea Bas in, tectonic evolu tion of the basin w as divided in to three periods Th e period of dep os ition of T aizhou Fun ing Formation was a pros perous period of th e bas in d evelopment, in w h ich the ex tensional ratio and deposition ratio of the bas in w ere max imum T he erosion intensity of W ubao Event w as stronger in th e east and w eaker in th e w est Th e period of the deposition of Dainan Sanduo Formation w as a typical development period of a rift basin, of w h ich ex tensional ratios and depositional ratios w ere low er th an that of the previous period For the effect of th e San duo event, from th e analysis of its p reservation state, in tegrated strata w ere p reserved in the depression and th ey w er e less pres erved in hum ped and slope ar eas , and it w as less eroded in the south depres sion and more in the north depres sion After Sanduo event, the basin is tu rned from rift ba s in to depression basin, the earlier separated sedimen t of the rift bas in is tu rned to a un ified sedim ent of depression deposit Key words:ex tensional ratio analysis; sub side ratio an aly sis; tectonic evolution; n orth ern Jiangsu South Yellow S ea Basin
32C haracteristics of Light Hydrocarbon Inclusions and Reservoir Formation Stages of Xia erm en Oilfield in Biyang Depression
(A uth or s Ad d ress :Dep artment of Oilf ield E xp loration, H enan Oilf ield Comp any , S IN OP EC, N anyang 473132LU Ming jiu
H enan, China)
Abstract::Core s am ples w ere collected from th e third member of H etaoyuan Formation of Xiaermen Oilfield in Biyang Depres sion, in w h ich inclu sions w ere s tu died by petrology analysis, flu or os copy analysis and u niform ity tem peratu re measu rement T he res ults indicate th ere are three stages of hydrocarb on inclusions , w hich corres pon ds to three formation stages of reservoir resulted from bas in history a nalys is and therm al history analysis Hyd rocarb on inclusions analysis provides evidence for determin ing main reservoir formin g stages, w h ich indicates that the late Olig ocene Stag e is a less hyd rocarb on formation stage, and M iocene Pliocene u plift S tage (the end of Li aozhuang Formation) is a main primary hydrocarbon formation stage, T he third stage (Before Qu aternary Period ) mainly pr odu ces sec ondary hydrocarbon res ervoir It is r ecogniz ed th at it w ould be more reliable to synthesize the results of hydrocarbon inclusions an aly sis, b asin h istory analysis and th ermal history an aly sis
Key words :hydr ocarb on inclusion; formation stage of reservoir; hydrocarbon accum ulation; Biyan g Depression ; Xiaermen Oilfield
37C arbonif erous V olcanic Rock Geological Characteristics in Xinjiang Sanbao Depression
WANG Jio ng , LI Guang yun , DANG Lu rui, HU Jin qua n, WANG Wan pe ng (Fir st A uthor s A dd re ss :S chool of Oil and
Gas Eng inee ring , Chong qing Univ ersity of S cience and T ech nolog y , Chong qing 401331, China)
Abstract:To study the carboniferou s oil and gas in Sanbao Depression of Xinjiang Ar ea, based on the data of field outcrops, heavy mag n eto electric detection and data collected from seism and drillin g in recent operation s, the conditions of oil gas geology of th e carb onifer ous volcanic r ocks in S anb ao Depres sion w ere preliminarily s tu died It is dem on strated that it h as the condition of hydrocarbon accumula tion w ith good prospects of oil and gas exploration It is pointed out that H uanglugang Structure is the favorable explor ation z on e of Car b oniferous oil and gas in Sanbao Depression, w here th e No 1T rap in H uanglugang Structure is the firs t selection of carboniferou s oil and gas ex ploration
Key words :Sanbao Depr ess ion; carb oniferous; volcanic rock; geologic characteristics ; favorable exploration z one
41Study on Eq 3Sedimentary Microfacies and Its Oil bearing Property in the South of Daqingzijing Oilf ield
WANG An hui , ZHAO Qua n jun (A uth or s Ad d ress :Qian an Oil Pr od uction Plant, J ilin Oil Comp any , CNP C, Song yuan
138003, J ilin, China)
Abstract:Eq 3in the s ou th of Daqingzijin g Oilfield w as one of the main target zones for oilfield ex ploration T herefore it w as of great sig nificance for oilfield ex ploration and developm ent by correctly r estoring the type of sedimentary m icrofacies an d its ar eal dis tribution and studying th e relationsh ip betw een the sedimen tary m icrofacies and oil gas distrib ution Th e s edimentary facies signs us ed for s tu dy in cludes rock colour, lithology, particle size, r ock structure, s edim entary tectonics and log facies, th e study reveals that E q 3in the s tu died area is a delta plain subfacies, and 4sedimen tary microfacies such as distributary ch ann el, crevasse splays, river overflow s sh ore sand b ody and distributary b ay are fu rth er identified and plain dis tr ibution rules of the sedimentary microfacies in each layer are restored on th e b asis stated above, the control of sedimentary micr ofacies on oil and gas accumulation is analyzed Key words:south of Daqingzijing Oilfield; E q 3; sedimen tary microfacies; oil bearing sand bodies
45Geochemical Characteristics and C omprehensive Evaluation of Source Rocks of Yingcheng Formation in Lishu Fault Depres sion of Southern Songliao Basin
ZH ANG Ju n (Author s A ddress:Research I nstitute of Petrole um Ex ploration and Development, SINOPEC, Beij ing 100083, China)
Abstract:T he data of regional g eological survey an d organic g eoch emical measu rement from Lishu Fault Depres sion of southern Songliao Basin w ere used to comprehen sively evaluate the source rocks fr om the aspects of organic matter abundance, its types an d maturity Th e resu lts show that sour ce rocks of Yingch eng Form ation are mainly developed in Sh iw u, Gujiazi and S iw ujiazi Ar eas, their m axim um th ickness are more than 500m; the source r ocks have high organic matter ab undance, they belong to med good rank source rocks ; th e organic m atter type is dom inated by k erogen of Type II1, the nes t is k erogen of Type III; matu rity of organic matter are gr eatly different in various region s, source rocks of Xiaoch engzi, Gujiazi and Shiw u areas ar e highly matured, they are at over matur e stage thos e of th e g entle slope belt are at m ature an d high m ature stages in the southw es t of the fault depression In addition, sour ce rocks from S huanglong Area in the n orth east of th e fault depres sion are at low mature stage Seein g from the source rock condition s, it reveals that source rocks of Yin gcheng Formation provide enorm ou s m aterial storage conditions for deep or shallow hydrocarbon accumulation in Lish u Fault De pr ess ion in the s ou thern Songliao Basin
Key words :sou rce rock evalu ation; hydrocarbon genesis potential; Yingcheng Form ation; Lishu Fault Dep ress ion
49Differences between Gas Hydrate Formation Patterns in Arctic Permafrost Region and Marine Environm ent
CHEN Yong qiao , LI We i hua , WANG Ling x ia , YANG Xi li (First A uthor s A d dr ess:Geoche mistry Dep artment, Yang tz e
Univ er sity ; K ey L aborator y of E xp loration T ech nology f or Oil and Gas Re sour ces (Yang tz e Univ er sity ) , M inistry of E du cation, Jingz hou 434023, H ube i, China)
Abstract:Th e natural en viron men t in arctic permafrost region and marin e environm ent w ere completely different, therefore the res ervoir formation patterns of gas hydrate in thes e tw o en viron men ts should be ess entially different Because of differ ent reservoir formin g patterns and different hydrate formin g modes, th erefore th e thinking s and meth ods for looking for it w er e different Based on the formation pat terns an d basic conditions in tw o different environments, the differen ces b etw een th e patterns of gas hyd rate formation in tw o different environments w ere discus sed It is consid ered by analysis th at deep pyrolysis methane gas is the m ain formation pattern in permafrost r e
2
石油天然气学报(江汉石油学院学报) 2010年12月 第32卷 第6期
2010 Vol 32 No 6Journal of Oil and Gas Technology (J JPI) Dec
27
苏北 南黄海盆地的构造演化分析
刘东鹰
(中石化江苏油田分公司地质科学研究院, 江苏扬州225009)
[摘要]通过苏北 南黄海盆地的拉张率和沉降率等的分析认为, 苏北 南黄海盆地的构造演化主要分为3个阶段。K 2t E 1f 沉积时期是苏北 南黄海盆地发育的兴盛期, 这一时期盆地的拉张率最大, 沉积速率也最大, 吴堡运动剥蚀强度具有东强西弱的特点。E 2d E 2s 沉积时期为典型断陷盆地发育期, 这一时期的盆地的拉张率和沉降率一般都小于前一时期。三垛运动使得凹陷保存地层较全, 凸起、斜坡保存地层较少; 南坳地层剥蚀少, 北坳地层剥蚀多; 三垛运动后, 盆地由断陷转为拗陷, 早期分割的断陷沉积转为统一的拗陷沉积。
[关键词]拉张率分析; 沉降率分析; 构造演化; 苏北 南黄海盆地[中图分类号]T E121 2
[文献标识码]A
[文章编号]1000 9752(2010) 06 0027 05
苏北 南黄海盆地是发育在扬子板块下扬子区构造形变极为复杂的中古生界基底之上的中新生界陆相盆地, 是由晚白垩世和新生代地层构成的沉积盆地。晚白垩世和新生代的沉积盖层可以分为泰州组(K 2t) 、阜宁组(E 1f) 、戴南组(E 2d) 、三垛组(E 2s) 、盐城组(N 2y) 、东台组(Qd) 等。包含有4个主要不整合, 即:盆地基底不整合面(K 2t 、E 1f 与下伏地层之间的不整合面) 、E 2d 与下伏地层之间的不整合面、E 2s 与下伏地层之间的不整合面、N 2y 与下伏地层之间的不整合面, 这4个不整合面的构造运动分别命名为仪征运动、吴堡运动、真武运动和三垛运动。许多学者对苏北 南黄海盆地的构造演化和形成机制进行了研究, 存在不同的观点和结论论盆地的构造演化和各时期盆地的性质。
[1~7]
。笔者通过对盆地的拉张率和沉降率等的分析, 讨
1 盆地拉张率分析
根据苏北 南黄海盆地的10余条地震解释剖面计算(表1) 认为, 虽然在不同凹陷、不同时期的拉
表1 苏北 南黄海盆地主要凹陷拉张率
凹陷及测线
洪泽凹陷
金湖凹陷
xus 1270Sg38 5M Q42小计G44G78G78H N117 5小计NY8346线46线
拉张率/%
K 2t E 1f 112 19 35 47 78 75 63 85 64 67 07 312 2
E 1f 2 E 1f 4
8 37 38 57 812 115 34 95 85 36 314 0
E 2d
5 51 26 33 311 73 77 64 46 02 417 017 0
E 2s
12 56 36 76 48 24 03 77 15 53 414 38 5
高邮凹陷
溱潼凹陷海安凹陷
盐城凹陷
南黄海南部南四凹南黄海南部南五凹
注:表中xu s1270、Sg38 5、M Q42 为地震测线号。
[收稿日期]2010 09 14
[基金项目]国家科技重大专项(2008ZX05005 003 005) 。
[作者简介]刘东鹰(1961 ) , 男, 1982年华东石油学院毕业, 博士, 高级工程师, 现主要从事石油地质勘探工作。
张率存在差异, 但具有一定的规律性。
从凹陷间拉张率的变化分析, 泰州组 阜一段(K 2t E 1f 1) 沉积时期, 西部的洪泽、金湖凹陷和中部的高邮凹陷、南黄海南部的南五凹拉张率相对较大, 分别为12 1%、7 7%、8 7%、12 2%。阜二段 阜四段(E 1f 2 E 1f 4) 沉积时期, 中部的高邮、溱潼凹陷、南黄海南部的南五凹较大, 分别为12 1%、15 3%、14 0%。E 2d 沉积时期, 拉张率最大的凹陷转移到东部南黄海南部盆地的南四凹、南五凹, 都为17%; 同时中部的高邮凹陷保持较大的拉张率, 为11 7%。E 2s 沉积时期, 拉张率较大的分布在盆地的东西两端, 分别为西部的洪泽凹陷和东部的南四凹、南五凹, 拉张率分别为12 5%、14 3%和8 5%。总之, 除高邮凹陷一直保持较大的拉张率之外, 拉张率大的凹陷从K 2t E 1f 1沉积时期至E 2d 沉积时期由西部向东部转移, 至E 2s 沉积时期转移到盆地两端; 从沉积的时间序列分析, 拉张率的变化大体存在两个阶段。K 2t E 1f 4沉积时期, 除洪泽凹陷、盐城凹陷外, 其他各凹陷拉张率逐步增加。E 2d 沉积时期, 除高邮凹陷、海安凹陷、南四凹、南五凹外, 其他各凹陷拉张率降至最低。
2 盆地沉降率分析
从苏北盆地各凹陷沉降率对比分析可知(表2) , 沉降史可分为3个阶段, K 2t E 1f 4沉积阶段, 沉降率为慢! 快! 慢! 快两个旋回; E 1f 2、E 1f 4沉积阶段沉降率较大, 其中E 1f 4沉积阶段在各个阶段中沉降率最大。虽然各凹陷沉降率差别较大, 但总体上是西部和中部各凹陷大于东部各凹陷。E 2d E 2s 沉积阶段, 沉降率为慢! 快! 慢的完整旋回, 西部和中部各凹陷的沉降率明显大于东部各凹陷。E 2y Qd 沉积阶段, 为慢! 快的正旋回, 各凹陷沉降率的关系与前两个阶段相反, 东部各凹陷明显大于西部和中部各凹陷。从各个阶段对比来看, K 2t E 1f 4沉积阶段的沉降率在各阶段中最大, 是盆地快速沉降期。
表2 苏北盆地各凹陷沉降率
层位K 2t E 1f 1E 1f 2E 1f 3E 1f 4E 2d 1E 2d 2E 2s 1E 2s 2E 2y 1E 2y 2Qd
沉降率/m M a -1
金湖15445532 5101 2457570 562 56 5830
高邮5 835 590
5515545 545655515 527 539 5
溱潼5 73590 5
20194 [1**********] 53549 5
海安52065 5
31152 510 57 5555232 538114 5
102048 53017 54582 5白驹103055 5
盐城10 53057 5
55122 519 51565 54015 52555 5
苏北盆地各时期的沉降率与拉张率有一定的正相关关系。时间序列比较, K 2t E 1f 沉积阶段, 拉张率大、沉降率也相对较大, E 2d 、E 2s 沉积阶段拉张率较小、沉降率也较小; 各凹陷间对比, 高邮凹陷
总体拉张率大、沉降率也大, 金湖、盐城凹陷总体拉张率小、沉降率也小。表明地层的沉降受断裂拉开速率的控制。
南黄海盆地的沉降率与苏北盆地极为类似[8](表3) , K 2t E 1f 沉积阶段为快速沉降期, 南坳最大达137m /M a, 北坳最大达138m/M a 。E 2d E 2s 沉积阶段, 沉降率基本为慢! 快的正旋回。E 2y Qd 沉积阶段, 也为慢! 快的正旋回。表明期构造演化史与苏北盆地类似。
表3 南黄海盆地各时期沉降率
构造单元K 2t E 1f 1E 1f 2E 1f 3E 1f 4E 2d E 2s 1E 2s 2E 2y 1E 2y 2Qd
南坳
地层厚度/m
24148367 5332 5508 526196 5402 5666 5815 5344
压实率0 310 31
0 360 360 360 430 430 430 650 81
沉降率/m M a -12 615
[***********]3
1
北坳
地层厚度/m
574439 [**************]1剥蚀389637257 5
0 650 81
294747
压实率0 310 31
0 360 360 360 430 43
沉降率/m M a -1
30138
[1**********]8
3 苏北 南黄海盆地构造演化
由于受扬子板块与华北板块碰撞和古太平洋板块的右旋挤压的作用, 中生代中国大陆的地形总体为东高西低的特征。这一时期苏北 南黄海盆地区总体海拔高度在2000m 以上。晚白垩世以来, 由于太平洋板块的高角度俯冲, 中国东部虽然转换为伸展拉张环境, 但地形、地貌仍然继承早期的特征, 浦口组、赤山组的沉积呈现出高原湖泊、高原沙漠特点。仪征运动虽然对早期的地层进行了剥蚀改造, 但从前K 2t 残留的地层分布看(图1) , 仍是东老西新、南老北新, 推测苏北 南黄海盆地区的地形为东高西低、南高北低。但由于江南古陆的存在, 盆地西南部也存在物源区。苏
北 南黄海盆地形成于晚白垩世仪征运动。盆地是在继承早期的地形、地貌特征的基础上, 在持续拉张环境下发生、发育起来的。3 1 盆地发育的兴盛期
K 2t E 1f 沉积时期是苏北 南黄海盆地发育的兴盛期, 这一时期盆地的拉张率最大, 沉积速率也最大。与全球海平面的升降相对应, 湖盆也经历3次水体上升的过程, 形成了3个正旋回沉积:K 2t 正旋回、E 1f 1 E 1f 2正旋回和E 1f 3 E 1f 4正旋回。各旋回的上部均受过海侵的影响, 以半深湖 深湖相暗色泥岩沉积为主, 构成主要生油岩系。旋回下部为河流 三角洲、扇三角洲体系, 具有较好的储集条件。强烈的拉张和深陷, 以及水体大幅上升(海侵) 的叠加效应, 使K 2t E 1f 地层的厚度受边界断层控制, 呈现出∀箕状#凹陷的特点, E 1f 2∀七尖峰#稳定标志层段的厚度变化是这一特征的有力表述。沉
[9]
[8]
图1 前K 2t 残留地层分布推断图
30
石油天然气学报(江汉石油学院学报) 2010年12月
积相的变化却显示了∀坳陷#沉积的特点。说明K 2t 、E 1f 2、E 1f 4沉积时期湖盆面积迅速扩大, 水体大幅上升, 盆地中的凸起、凹陷均处于较深水环境, 凹陷的边界断层对沉积的控制作用仅表现为厚度变化, 而沉积相未受到明显影响。
E 1f 4沉积以后的吴堡运动使盆地抬升。伴随着全球海平面的下降, 湖盆中的水体也随之下降, 进而全部退出苏北 南黄海盆
地区, 沉积岩广泛暴露地
表, 遭受风化、剥蚀。受这一时期剥蚀强度有东强西弱的特点(图2) 。3 2 盆地典型断陷发育期
E 2d E 2s 沉积时期为典型断陷盆地发育期。水体再次进入盆地。E 2d 沉积时期, 由于水体范围小, 所以盆地具有较强的分割性。受边界断层控制, 地层厚度变化很大。沉积相特征为靠边界断层一侧为水下扇体系, 斜坡一侧为河流 三角洲体系。具有典型的箕状断陷盆地特征。E 2s 沉积时期水体扩大, 形成广泛的超覆, 从下部的河流、沼泽相沉积转变为上部的浅湖相沉积。
E 2s 沉积后的三垛运动, 是由于受印度板块与欧亚板块碰撞的影响, 盆地区从近东西向的拉张环境转变为近南北向的挤压环境, 盆地区整体抬升, 遭受长时间的剥蚀。从E 2s 地层保存状况分析(图3) , 凹陷保存地层较全, 凸起、斜坡保存地层较少; 南凹地层剥蚀少,
北凹地层剥蚀多。
[10, 11]
图2 前E 2d 残留地层分布图
图3 苏北 南黄海盆地E 2s 对比图
第32卷第6期刘东鹰:苏北 南黄海盆地的构造演化分析
31
3 3 盆地拗陷发育期
三垛运动后, 盆地由断陷转为拗陷, 早期分割的断陷沉积转为统一的拗陷沉积。断陷期形成的张性断裂, 除凹陷边界同生断裂活动到N 2y 1沉积时期外, 大部分在拗陷期停止活动。由于受印度板块的长期推挤作用, 盆地的西部抬升, 东部下沉, 沉降量由早期的∀西大东小#变为盐城期的∀东大西小#。同时在盆地东西两侧的少量早期正断层反转为逆断层。
4 结 论
1) 总体而言, K 2t E 1f 沉积时期的拉张率大于以后各沉积时期的拉张率。各凹陷在不同沉积时期的拉张率有一些变化, K 2t E 1f 1沉积时期, 西部和中部各凹陷拉张率相对较大; E 1f 2 E 1f 4沉积时期, 中部各凹陷较大; E 2d 沉积时期, 拉张率最大的凹陷转移到东部南黄海南部盆地的南四凹、南五凹, 同时中部的高邮凹陷保持较大的拉张率; E 2s 沉积时期, 拉张率较大的分布在盆地的东西两端。
2) 沉降史可分为3个阶段, 在各沉积时期中, E 1f 2、E 1f 4沉积阶段沉降率较大。沉降率与拉张率有一定的正相关关系。时间序列比较, K 2t E 1f 沉积阶段, 拉张率大、沉降率也相对较大; E 2d 、E 2s 沉积阶段拉张率较小、沉降率也较小。
3) 苏北 南黄海盆地的构造演化主要分为3个阶段。K 2t E 1f 沉积时期是苏北 南黄海盆地发育的兴盛期; E 2d E 2s 沉积时期为典型断陷盆地发育期, 这一时期的盆地的拉张率和沉积速率一般都小于前一时期; 三垛运动后, 盆地由断陷转为拗陷, 早期分割的断陷沉积转为统一的拗陷沉积。
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[编辑] 宋换新
ples or the s imilarity betw een th e phase variables, it w as classified s tep by step By taking W ellb lock Xi259in C heng hao Oilfield for exam ple, Q h ierarchical clustering m ethod of cluster analysis w as u sed to s tu dy the type of C32reservoir, and s am ples w ere class ified, by w h ich the law of spatial distribution of r eservoirs w as ob tained Th e r esults sh ow that th e m ethod for reservoir evaluation is feasible w ith high rationality
Key words :reservoir evaluation; clu ster analysis; Q type h ierarch ical clustering method; Chenghao Oilfield
27Analysis on Structural Evolution of Northern Jiangsu South Yellow Sea Basin
LIU Do ng y ing (Au thor s Ad d ress :Re search Institute of G eosc ienc es, J iangsu Oilf ie ld Company , SI N OP EC, Yang zh ou
225009, J iang su, China)
Abstract:By analysis of exten sion ratio and sub side ratio of northern Jiangsu S ou th Yellow S ea Bas in, tectonic evolu tion of the basin w as divided in to three periods Th e period of dep os ition of T aizhou Fun ing Formation was a pros perous period of th e bas in d evelopment, in w h ich the ex tensional ratio and deposition ratio of the bas in w ere max imum T he erosion intensity of W ubao Event w as stronger in th e east and w eaker in th e w est Th e period of the deposition of Dainan Sanduo Formation w as a typical development period of a rift basin, of w h ich ex tensional ratios and depositional ratios w ere low er th an that of the previous period For the effect of th e San duo event, from th e analysis of its p reservation state, in tegrated strata w ere p reserved in the depression and th ey w er e less pres erved in hum ped and slope ar eas , and it w as less eroded in the south depres sion and more in the north depres sion After Sanduo event, the basin is tu rned from rift ba s in to depression basin, the earlier separated sedimen t of the rift bas in is tu rned to a un ified sedim ent of depression deposit Key words:ex tensional ratio analysis; sub side ratio an aly sis; tectonic evolution; n orth ern Jiangsu South Yellow S ea Basin
32C haracteristics of Light Hydrocarbon Inclusions and Reservoir Formation Stages of Xia erm en Oilfield in Biyang Depression
(A uth or s Ad d ress :Dep artment of Oilf ield E xp loration, H enan Oilf ield Comp any , S IN OP EC, N anyang 473132LU Ming jiu
H enan, China)
Abstract::Core s am ples w ere collected from th e third member of H etaoyuan Formation of Xiaermen Oilfield in Biyang Depres sion, in w h ich inclu sions w ere s tu died by petrology analysis, flu or os copy analysis and u niform ity tem peratu re measu rement T he res ults indicate th ere are three stages of hydrocarb on inclusions , w hich corres pon ds to three formation stages of reservoir resulted from bas in history a nalys is and therm al history analysis Hyd rocarb on inclusions analysis provides evidence for determin ing main reservoir formin g stages, w h ich indicates that the late Olig ocene Stag e is a less hyd rocarb on formation stage, and M iocene Pliocene u plift S tage (the end of Li aozhuang Formation) is a main primary hydrocarbon formation stage, T he third stage (Before Qu aternary Period ) mainly pr odu ces sec ondary hydrocarbon res ervoir It is r ecogniz ed th at it w ould be more reliable to synthesize the results of hydrocarbon inclusions an aly sis, b asin h istory analysis and th ermal history an aly sis
Key words :hydr ocarb on inclusion; formation stage of reservoir; hydrocarbon accum ulation; Biyan g Depression ; Xiaermen Oilfield
37C arbonif erous V olcanic Rock Geological Characteristics in Xinjiang Sanbao Depression
WANG Jio ng , LI Guang yun , DANG Lu rui, HU Jin qua n, WANG Wan pe ng (Fir st A uthor s A dd re ss :S chool of Oil and
Gas Eng inee ring , Chong qing Univ ersity of S cience and T ech nolog y , Chong qing 401331, China)
Abstract:To study the carboniferou s oil and gas in Sanbao Depression of Xinjiang Ar ea, based on the data of field outcrops, heavy mag n eto electric detection and data collected from seism and drillin g in recent operation s, the conditions of oil gas geology of th e carb onifer ous volcanic r ocks in S anb ao Depres sion w ere preliminarily s tu died It is dem on strated that it h as the condition of hydrocarbon accumula tion w ith good prospects of oil and gas exploration It is pointed out that H uanglugang Structure is the favorable explor ation z on e of Car b oniferous oil and gas in Sanbao Depression, w here th e No 1T rap in H uanglugang Structure is the firs t selection of carboniferou s oil and gas ex ploration
Key words :Sanbao Depr ess ion; carb oniferous; volcanic rock; geologic characteristics ; favorable exploration z one
41Study on Eq 3Sedimentary Microfacies and Its Oil bearing Property in the South of Daqingzijing Oilf ield
WANG An hui , ZHAO Qua n jun (A uth or s Ad d ress :Qian an Oil Pr od uction Plant, J ilin Oil Comp any , CNP C, Song yuan
138003, J ilin, China)
Abstract:Eq 3in the s ou th of Daqingzijin g Oilfield w as one of the main target zones for oilfield ex ploration T herefore it w as of great sig nificance for oilfield ex ploration and developm ent by correctly r estoring the type of sedimentary m icrofacies an d its ar eal dis tribution and studying th e relationsh ip betw een the sedimen tary m icrofacies and oil gas distrib ution Th e s edimentary facies signs us ed for s tu dy in cludes rock colour, lithology, particle size, r ock structure, s edim entary tectonics and log facies, th e study reveals that E q 3in the s tu died area is a delta plain subfacies, and 4sedimen tary microfacies such as distributary ch ann el, crevasse splays, river overflow s sh ore sand b ody and distributary b ay are fu rth er identified and plain dis tr ibution rules of the sedimentary microfacies in each layer are restored on th e b asis stated above, the control of sedimentary micr ofacies on oil and gas accumulation is analyzed Key words:south of Daqingzijing Oilfield; E q 3; sedimen tary microfacies; oil bearing sand bodies
45Geochemical Characteristics and C omprehensive Evaluation of Source Rocks of Yingcheng Formation in Lishu Fault Depres sion of Southern Songliao Basin
ZH ANG Ju n (Author s A ddress:Research I nstitute of Petrole um Ex ploration and Development, SINOPEC, Beij ing 100083, China)
Abstract:T he data of regional g eological survey an d organic g eoch emical measu rement from Lishu Fault Depres sion of southern Songliao Basin w ere used to comprehen sively evaluate the source rocks fr om the aspects of organic matter abundance, its types an d maturity Th e resu lts show that sour ce rocks of Yingch eng Form ation are mainly developed in Sh iw u, Gujiazi and S iw ujiazi Ar eas, their m axim um th ickness are more than 500m; the source r ocks have high organic matter ab undance, they belong to med good rank source rocks ; th e organic m atter type is dom inated by k erogen of Type II1, the nes t is k erogen of Type III; matu rity of organic matter are gr eatly different in various region s, source rocks of Xiaoch engzi, Gujiazi and Shiw u areas ar e highly matured, they are at over matur e stage thos e of th e g entle slope belt are at m ature an d high m ature stages in the southw es t of the fault depression In addition, sour ce rocks from S huanglong Area in the n orth east of th e fault depres sion are at low mature stage Seein g from the source rock condition s, it reveals that source rocks of Yin gcheng Formation provide enorm ou s m aterial storage conditions for deep or shallow hydrocarbon accumulation in Lish u Fault De pr ess ion in the s ou thern Songliao Basin
Key words :sou rce rock evalu ation; hydrocarbon genesis potential; Yingcheng Form ation; Lishu Fault Dep ress ion
49Differences between Gas Hydrate Formation Patterns in Arctic Permafrost Region and Marine Environm ent
CHEN Yong qiao , LI We i hua , WANG Ling x ia , YANG Xi li (First A uthor s A d dr ess:Geoche mistry Dep artment, Yang tz e
Univ er sity ; K ey L aborator y of E xp loration T ech nology f or Oil and Gas Re sour ces (Yang tz e Univ er sity ) , M inistry of E du cation, Jingz hou 434023, H ube i, China)
Abstract:Th e natural en viron men t in arctic permafrost region and marin e environm ent w ere completely different, therefore the res ervoir formation patterns of gas hydrate in thes e tw o en viron men ts should be ess entially different Because of differ ent reservoir formin g patterns and different hydrate formin g modes, th erefore th e thinking s and meth ods for looking for it w er e different Based on the formation pat terns an d basic conditions in tw o different environments, the differen ces b etw een th e patterns of gas hyd rate formation in tw o different environments w ere discus sed It is consid ered by analysis th at deep pyrolysis methane gas is the m ain formation pattern in permafrost r e
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