为评估某模块钻机井架产生裂纹的风险,在对井架进行整体有限元分析的基础上,采用扩展有限元方法分析裂纹扩展规律.为验证井架修复后的结构强度,对井架修复局部进行结构校核,并依据标准对井架整体进行应力测试.结果 表明,井架结构修复方案可行,井架承载能力满足设计及标准要求.

目前,临兴致密砂岩气藏主要采取直井压裂,但压后产量普遍达不到预期效果,对此,需要借鉴页岩气藏缝网压裂的成功经验,以探索直井缝网压裂是否可行.根据缝网形成的理论条件,对临兴致密砂岩气藏直井缝网压裂可行性进行了定量分析.分析了临兴致密砂岩气藏天然裂缝发育情况、地应力差异和岩石矿物组成等储层物理特征,认为该气藏具有实现缝网压裂的客观条件.同时,从水力压裂工艺方面,根据压裂诱导应力的计算结果,并与地层水平主应力差进行了对比,认为采取合理的缝内暂堵转向后,能够实现直井缝网压裂.上述2个方面的分析表明直井缝网压裂完全可行,这将为致密砂岩气藏的高效开发提供重要的技术支撑.

综合利用钻井、地震等资料,对南黄海盆地南五凹新生代构造演化和沉积充填特征进行了研究,重点分析了南五凹烃源岩、储盖组合、圈闭类型和运聚条件,结果表明:南五凹新生界具有“坳-断-坳”三层结构;阜宁组半深—深湖相泥岩在南部陡断带、中部反转带和北部缓坡带均有发育,具有面积广、厚度大的特点;阜宁组沉积期经历了广湖成化过程,成化湖泊烃源岩不仅规模大,而且生烃活化能低,生烃时间相对早,延长了排烃时间,极大地提升了凹陷的资源潜力;戴南组扇三角洲与滨浅湖相沉积在纵向上形成了3套有利的储盖组合;边界断层及凹陷内部的次级断层长期发育,是有效的油源通道;南部陡断带和中部反转构造带上发育多个规模较大的断背斜或断鼻型圈闭,是有利的油气运移指向区和勘探潜力方向.本文研究结果对南黄海盆地油气勘探具有指导意义.

随着临兴致密气藏某区块地质勘探开发一体化的需要,裸眼侧钻技术成为重要的钻井工艺之一,钻井过程中若对侧钻技术不熟悉或多方配合欠佳将出现侧钻周期长、浪费进尺多、工具和仪器在井下时间过长会造成严重磨损,粘卡或信号出问题,甚至出现侧钻失败的现象.本文浅议了裸眼侧钻过程的几个关键问题;侧钻点优选依据;结合井底力学分析模型,评价和优选出最佳的侧钻工具;使用合理参数侧钻进新井眼后现场判断依据等.该技术在LX-XX井裸眼侧钻成功应用,表明以上技术完全适应于该区块的侧钻需要.

At present, the fracture conductivity is tested by using water as driving medium, but the shale core will swell easily with water, and there is not existing water during the shale gas production, thus, the conductivity tested by water cannot represent the fracture permeability in shale gas reservoir. For this problem, the API conductivity cell has been modified to test the fracture conductivity by using N2 as driving medium. The conductivities for 40/70 resin coated sand and ceramic proppant have been tested under four types of sand concentrations. The experiment results showed that, for the two types of proppants, the conductivity decreased significantly when the closure pressure increased, and the conductivity of resin coated sand decreased more larger than that of ceramic proppant; The conductivity with high sand concentration was higher than the low concentration in low closure pressure; At the same sand concentration, the conductivity of ceramic proppant was larger than that of resin coated sand. Besides, theoretical analysis showed that, when the propped fracture kept a certain width, in the level of mm or even um order of magnitude, its permeability was still higher than that of shale reservoir. The fracture conductivity tested by N2can reflect the shale formation truly, thus the experimental results can provide reliable basis for sand concentration selection and fracturing design in shale gas reservoirs.

No commercial hydrocarbon is discovered till now in Nanwu sag of the southern depression in the South Yellow Sea basin, and the hydrocarbon resources potential evaluation is poorer by previous research.However, about 200 million tons oil reserves in place were discovered by the end of 2011 in Gaoyou sag of Subei basin, which is nearby the South Yellow Sea basin and both have the similar geological features.To further evaluate the resource potential in Nanwu sag more clearly, the generation kinetics model widely used internationally is adopted to simulate the generation and expulsion history of source rock, in which the parameters of the generation kinetics model are from Rock-Eval analysis of samples of the source rock and the asphaltenes, and are confirmed by the maturity distribution of reserves in place.Results show that the activation energy of the Funing source rock is 209 kJ/mol which is lower than typical lacustrine source rock, and hydrocarbon can be generated in lower maturity.The Funing source rock has the characteristics of early generating and expelling.The oil expulsion amount is up to 2950 million m3, and the resources of oil in place is about 270 million~410 million m3, which is comparable with that of Gaoyou sag.Next step wells should be drilled in the prospects with larger hydrocarbon accumulation area and better trap conditions to get commercial discovery much early.

Based on the analysis of gravity data,magnetic data,interpretation of seismic data and the research of NW structures in the periphery,the tectonic evolution and fault characteristics of North Jiangsu and South Yellow Sea Basin were analyzed,which reveals the different forms of NW structures between onshore and offshore in the basin.Moreover,the constraint of NW trending faults during the hydrocarbon accumulation in the offshore area were clarified.The results show that there are three depocenters in Nanwu sag in the fault depression period,when the NW trending fault stretching rate is 12％-14％,and the maximum active rate is 170 m/Ma,which controls the development of the source rock of Funing formation.Three NW transfer zones are identified in the onshore area,which break and constrain the distribution of seven sag-control faults and Jianhu Uplift.Three NW trending faults are identified in the offshore area,which control the plane forms of Naner sag and Nanwu sag,and make the Nansi sag,Nanliu sag and Nanqi sag an echelon arrangement.The offshore hydrocarbon accumulation are controlled by the NW trending structure,and mainly distributed near the depocenter of Funing formation.

The XH sag in East China Sea is dominated by sedimentary formation of sandstone and mudstone interbeds,small interface layer impedance difference,and shallow water multiples,resulting in weak seismic reflection and unobvious wave characteristics.This study makes the fine processing of the seismic data by applying noise suppression,deghost multiple attenuation,high precision broadband processing and other technologies The processing of wave characteristics section is significantly improved.The data of low frequency and high frequency are broadened,and the wave is more reliable.The results of treatment of wave impedance inversion and integrated interpretation can better analyze the main control factors of the depression of high quality reservoir,lithology and drilling.The high degree of coincidence confirms the seismic data processing of high reliability,and reaches the sandstone mudstone layer of high quality seismic data imaging.

Three types of positive inversion structures are found in the North Sag of South Yellow Sea Basin with interpretation of reprocessed 2D seismic data.They are classified into three types:the reversed fault type in the central and southern part,the transpressional type in the eastern part and the compressional fold type in the northern part.Where the inversion structures located was depended on the different tectonic positions.Based on the integrated analysis of balance sections of the typical seismic profiles and the regional tectonic background,it was considered that three episodic positive inversions had happened in the North Sag at least,which were influenced by the change of the subduction angle and rate from the Pacific plate to the Eurasian continent during the Cenozoic period.After the Sanduo Formation deposited,the subduction direction of the Pacific plate changed from NW to SWW and the subduction rate increased twice nearly.This change caused the most intensely positive inversion episode of the North Sag because of the SWW compressional force from the Pacific plate,which presented the strongest reversely faulting and erosion.Meanwhile,the excessively positive inversion may not be good for the hydrocarbon accumulation in the North Sag.

南黄海盆地南部坳陷是该盆地最具勘探突破潜力的地区,有8凹4凸,结构复杂.其中古近系阜宁组为1套厚度超1 km的湖相砂泥岩地层,可分为4段,是最重要的烃源岩.综合应用测井、岩芯、地震剖面、古生物资料以及与苏北盆地进行对比,在南部坳陷阜宁组共识别出3种主要沉积体系:湖泊、三角洲、碳酸盐台地.南部坳陷在阜宁组时期是中国东部一个大型的坳陷型湖盆,阜二段、阜四段沉积时期是南部坳陷的2次湖泛期,其典型特征为中深湖相发育且满盆发育,不发育边缘相;阜三段沉积时期是上述2次湖泛期之间的1次湖退期,典型特征是滨浅湖分布广泛.同时缓坡带发育大型三角洲,是典型的陆相坳陷湖盆的沉积发育模式.

烃源岩和热作用共同控制了中国近海含油盆地石油富集与贫化程度.近海含油盆地的主要烃源岩为半深湖—深湖相泥岩,分布层位包括古新统、始新统和渐新统,以始新统为主;有机质类型为腐泥型,有机质丰度从极高到低;半深湖—深湖相泥岩规模从数千平方千米到不甚发育.这些含油盆地的地温场从高到低都有存在,主要受地壳结构控制.凹陷烃源岩和热作用之间存在“源足热足”、“源足热欠”、“源欠热足”、“源欠热欠”4种基本类型.由于各含油盆地不同凹陷的烃源岩类型、有机质丰度、规模差异巨大以及凹陷的热场差别大,烃源岩与热作用耦合类型不同,形成了生油潜力极不相同的含油盆地.渤海盆地绝大多数凹陷源足热足,且发育一批极富的生油凹陷,盆地资源潜力堪称巨大.南海北部珠江口盆地北部坳陷带和北部湾盆地诸凹陷之间及同一凹陷内部差异性大,洼陷是基本单元,诸凹陷4种耦合类型都存在, “源足热足型”凹陷数量较多,部分凹陷富生油,勘探潜力大.南黄海盆地凹陷很多,但多数凹陷源较足、热不足,深洼槽才具有较大生油潜力,盆地勘探潜力一般.北黄海盆地各古近系凹陷源不足、热不足,凹陷生油少,属于贫油凹陷,盆地古近系凹陷资源潜力较小.中国近海石油的主要勘探领域在渤海盆地,其剩余石油资源占近海的多数;南海北部大陆边缘北部近岸盆地带居次;南黄海盆地占很小部分.渤海盆地的绝大多数凹陷和南海北部近岸内带的部分凹陷是近海的石油富集区,特别是渤海盆地郯庐西凹陷带是超级富生油区.

南黄海盆地一直未能取得商业性油气发现，为了能在南五凹取得勘探突破，对重新处理的高精度地震剖面进行了精细解释。研究发现，南五凹中南部发育有大型横向背斜，进一步的几何学和运动学分析表明，其形成机制主要受控于南部边界断层在空间上的几何形态变化。这些横向褶皱分布于南五凹深洼区，具有充足的油源供应，其上覆的戴南组能够形成多套有效储盖组合，边界断层及其上盘伴生的次级断层能够作为有利的油气运移通道，最终有可能形成规模可观的油气富集单元，具有重要的勘探实践意义。

地震资料的精细刻画揭示,南五凹东洼在结构上表现为南北两侧成洼、中部为大型断裂褶皱带的不对称地堑式.在平面上,中部背斜带在东洼的东、西部发生错位,可能是受斜向拉伸作用的影响.关键地质界面分析和盆地沉降史回剥恢复表明该区经历了断陷—隆升—坳陷的构造演化过程.结合沉降速率的变化规律和平衡剖面分析,盆地的断陷期可进一步划分为两个阶段.在上白垩统泰州组—古新统阜宁组(K2t-E1f)沉积时期,断层活动较弱,对沉积作用控制小,沉积中心位于洼陷的中部,整体表现为断拗的特征;在始新统戴南组—三垛组(E2d-E2s)沉积时期,边界断层对沉积的控制作用增强,沉积中心向南迁移,洼陷中部的断裂褶皱带逐渐定型,整体表现为断陷的特征.渐新世时期,南黄海盆地区域性隆升剥蚀.新近纪以后,南黄海盆地进入区域性拗陷期,东洼表现为稳定的热沉降过程.

The South Yellow Sea basin is a large size Mesozoic and Cenozoic sedimentary basin.Hydrocarbon exploration in this basin has been carried out for more than four decades,but no commercial hydrocarbon discovery has been obtained so far,with only one oil bearing structure Zhucheng 1-2 has been discovered.There are a lot of basic geological problems to be solved in this basin,including whether the excellent quality source rocks are well developed,whether hydrocarbon has been generated from the source rocks,and whether hydrocarbons can migrate into reservoirs.Based on evaluation results on source rocks,the hydrocarbon accumulation characteristics in the North Sag have been studied with fluid inclusion technique in this paper.The result showed that the second member of Taizhou formation is the main source rock,being semi-deep lacustrine fades,and distributes widely.The main source rocks have mature and large amount of oil and gas have been expulsed from the main source rocks.The hydrocarbon generation center was located in Well Block ZC-A.Hydrocarbon has migrated along faults and filled into the Eocene Dainan Formation.The results show that there were two phases of hydrocarbon charge at least in the Dainan formation based on the study results of fluorescence observation of fluid inclusion and the microscopic temperature measure.The first phase hydrocarbon charge happened in about35 Ma,and the second charge happened at present.

北凹是南黄海盆地北部坳陷最具勘探潜力的凹陷之一,是一个“北断南超”的典型箕状断陷湖盆,其中古近系阜宁组为一套厚度近2000m的河湖相砂泥岩地层,可分为4段.综合应用测井、岩芯、地震剖面等资料,分析北凹阜宁组沉积体系及沉积相,共识别出2种主要沉积体系:湖泊和扇三角洲沉积体系,基本继承了北部物源为主的沉积格局.凹陷中部为滨浅湖相沉积,是典型的陆相断陷湖盆的沉积发育模式.

南五凹是南黄海盆地南部坳陷最具勘探潜力的凹陷之一,是一个南断北超的典型萁状断陷湖盆,其中古近系戴南组为河湖相砂泥岩地层.综合应用测井、岩心、地震剖面等资料,共识别出3种主要的沉积体系:三角洲、湖泊、扇三角洲沉积体系,其基本继承了南部物源为主的沉积格局,北部三角洲不太发育,凹陷中部为滨浅湖相沉积.沉积相在平面上分布范围明确,纵向上既有差异性又有继承性.戴南组发育三套储盖组合,从矿物成分、实测孔隙度及砂岩厚度看储层发育,由丰富的油气显示体现了盖层的有效性,最有利的储盖组合是戴一段下部的组合.

Maichen Sag is a tertiary tectonic structure located in the south of Beibu gulf basin.Petroleum geological conditions and tectonic units in Maichen Sag was described,and the characteristics of tectonic evolution,structural styles and structural belt distribution were discussed in Maichen Sag in detail in this paper.()n this basis,the main controlling factors of hydrocarbon accumulation and the exploration target in Maichen Sag were evaluated.It's pointed out the studied region may be divided into four secondary sags,in which,Dong—1 secondary sag have the best source rocks of LiushagangⅡ,and there are many traps developed in the slope zone,so Dong- 1 secondary sag is the exploration target in Maichen Sag.