库车坳陷克深大气田白垩系致密砂岩储层古流体地球化学特征研究     

孙可欣  李贤庆  魏强  梁万乐  张亚超  李剑  肖中尧 《现代地质》2019,33(6):1220-1228

采用包裹体岩相学、均一温度、盐度、含油包裹体丰度、储层颗粒荧光定量实验分析方法,对库车坳陷克深大气田白垩系巴什基奇克组储层致密砂岩样品进行测试,剖析克深大气田深层致密砂岩储层古流体地球化学特征与油气充注。结果表明,克深大气田发育两期油气包裹体,分别为发亮蓝色荧光的轻质油包裹体与灰黑色的气态烃包裹体。克深大气田包裹体均一温度分布存在130~140 ℃与150~160 ℃两个主峰值,相应的古盐度值为16%~10%与12%~4%,表明有两期烃类流体充注,其中天然气高强度充注发生在2.5 Ma以来。含油包裹体丰度分布在2.1%~13.4%之间,QGF指数为2.2~9.6,QGF-E强度为20~38 pc,揭示克深大气田形成过程中曾经存在强度较弱的轻质油充注。  相似文献   

大地电磁测深在湘东南坳陷页岩气勘探中的应用     

田巍  李旭兵  王保忠 《物探与化探》2019,(2):281-289

为了解湘东南坳陷西南部地区深部构造特征,以及泥盆系—二叠系主要页岩气层系的分布、岩性等特征,以袁家向斜为研究对象,开展了4条大地电磁测深剖面资料的处理和定性、定量分析。通过对大地电磁测深资料的视电阻率拟断面、阻抗相位分析及二维连续介质反演,结合研究区的地质和物性特征,大致查明了剖面上主要断裂的位置、性质及发育特征,圈定了主要地质层系(电性层)的空间展布,并在此基础上探讨了该地区页岩气勘探的有利层系。研究成果表明:袁家向斜内部的断裂以SN向、NE向和NW向断裂为主,在剖面上多表现为铲式或坡坪式的构造样式;二叠系龙潭组发育优质含气性煤层,具有较好的煤层气勘探前景;泥盆系棋梓桥组下段低阻页岩连续且厚度大,可作为有利勘探页岩层系。  相似文献   

Discovery and Analysis of Shale Gas in a Carboniferous Reservoir and its Enrichment Characteristics in the Northern Nanpanjiang Depression,Guizhou Province,China     

LU Shufan  LUO Xiangjian  DU Shengjiang  HE Ben  FU Hongbin  LIU Kuiyong 《《地质学报》英文版》2019,93(3):561-572

Shale gas resources are considered to be extremely abundant in southern China, which has dedicated considerable attention to shale gas exploration in recent years. Exploration of shale gas has considerably progressed and several breakthroughs have been made in China. However, shale gas explorations are still scarce. Summary and detailed analysis studies on black shale reservoirs are still to be performed for many areas. This lack of information slows the progress of shale gas explorations and results in low quantities of stored black shale. The Carboniferous Dawuba Formation, which is widely distributed and considerably thick, is one of the black shale formations targeted for shale gas exploration in southern China in the recent years. The acquisition and analysis of total organic carbon, vitrinite reflectance,types of organic matter, mineral composition, porosity, and permeability are basic but important processes. In addition, we analyzed the microscopic pores present in the shale. This study also showesd the good gas content of the Dawuba Formation, as well as the geological factors affecting its gas content and other characteristics. To understand the prospect of exploration, we compared this with other shale reservoirs which have been already successfully explored for gas. Our comparison showesd that those shale reservoirs have similar but not identical geological characteristics.  相似文献   

南盘江盆地八渡辉绿岩斜锆石和锆石U-Pb年龄及其地质意义     

夏文静  闫全人  向忠金  夏磊  江文  李晓剑  周斌  邓莉 《地球学报》2019,40(2):265-278

南盘江盆地是华南板块西南缘最大的沉积盆地之一。它的构造属性、形成时间及机制长期存在争议,影响着对华南印支造山过程的准确理解。南盘江盆地内除三叠系填充物外,断续出露着古生代碳酸盐岩。这些古生代碳酸盐岩实为三叠纪盆地下伏地层在盆地伸展张开过程中形成的断隆,在这些断隆周边发育有似层状或脉状辉绿岩,记录了南盘江盆地发育初期或早期的地质演化信息。本文用CamecaIMS1280二次离子质谱仪对南盘江盆地东南部八渡辉绿岩中的斜锆石和锆石进行了U-Pb同位素测试,分别获得206Pb/238U年龄加权平均值(269.3±4.2)Ma(95%置信度,N=15,MSWD=0.27)和(265.0±2.9)Ma(95%置信度,N=8,MSWD=0.02),表明八渡辉绿岩侵位于中二叠世沃德期(Wordian;265.1～268.8Ma),指示了南盘江盆地在此时处于伸展构造体制。这与南盘江盆地内广泛发育晚二叠世—早三叠世(258～248 Ma)基性岩浆活动,以及南盘江盆地晚二叠世—早三叠世时期沉积环境由碳酸盐岩台地相沉积快速转变为以浊积扇相为主的深水沉积等地质事实,共同表明南盘江盆地在中二叠世—早三叠世处于伸展构造体制。  相似文献   

塔里木盆地东南坳陷侏罗系展布特征研究     

孙智超  苗苗青  王继勋  程明华  白忠凯  张金虎 《中国地质调查》2019,6(4):24-29

塔东南坳陷位于塔里木盆地的东南部,勘探程度较低。侏罗系为该区主要油气勘探目的层,明确塔东南坳陷侏罗系展布特征是实现该区油气突破的关键问题。通过分析2015年后实施的最新钻探工程以及最新采集处理的地震、电法剖面,结合钻测井、露头资料,研究塔东南侏罗系分布范围及厚度,结果表明侏罗系在塔东南坳陷广泛发育,仅在且末凸起西部局部地区缺失;瓦石峡凹陷侏罗系十分发育,沉积厚度大,分布范围广,并向阿尔金山前有明显加厚趋势,可作为塔东南坳陷油气勘探目标区。  相似文献   

Pleistocene sea‐floor fibrous crusts and spherulites in the Danakil Depression (Afar,Ethiopia)     

David Jaramillo‐Vogel  Anneleen Foubert  Juan Carlos Braga  Jean‐Charles Schaegis  Balemwal Atnafu  Bernard Grobety  Tesfaye Kidane 《Sedimentology》2019,66(2):480-512

Pleistocene fibrous aragonite fabrics, including crusts and spherules, occur in the Danakil Depression (Afar, Ethiopia) following the deposition of two distinctive Middle and Late Pleistocene coralgal reef units and pre‐dating the precipitation of evaporites. Crusts on top of the oldest reef unit (Marine Isotope Stage 7) cover and fill cavities within a red algal framework. The younger aragonite crusts directly cover coralgal bioherms (Marine Isotope Stage 5) and associated deposits. Their stratigraphic position between marine and evaporitic deposits, and their association to euryhaline molluscs, suggest that the crusts and spherules formed in restricted semi‐enclosed conditions. The availability of hard substrate controls crust formation with crusts more often found on steep palaeo‐slopes, from sea level up to at least 80 m depth, while spherules mainly occur associated with mobile substrate. Crusts reach up to 30 cm in thickness and can be microdigitate, columnar (branching and non‐branching) or non‐columnar, with laminated and non‐laminated fabrics. Two different lamination types are found within the crystalline fabrics: (i) isopachous lamination; and (ii) irregular lamination. These two types of lamination can be distinguished by the organization of the aragonite fibres, as well as the lateral continuity of the laminae. Scanning electron microscopy with energy dispersive X‐ray spectroscopy analyses on well‐preserved samples revealed the presence of Mg‐silicate laminae intercalated with fibrous aragonite, as well as Mg‐silicate aggregates closely associated with the fibrous aragonite crusts and spherules. The variety of observed fabrics results from a continuum of abiotic and microbial processes and, thus, reflects the tight interaction between microbially mediated and abiotic mineralization mechanisms. These are the youngest known isopachously laminated, digitate and columnar branching fibrous crusts associated with a transition from marine to evaporitic conditions. Understanding the context of formation of these deposits in Afar can help to better interpret the depositional environment of the widespread Precambrian sea‐floor precipitates.  相似文献   

渤海湾盆地辽河坳陷锦310预探井钻前储集层质量预测     

程仲平  孟元林  王粤川  王健  魏巍  牛嘉玉  孙洪斌  高建军  肖丽华 《古地理学报》2011,13(5):509-516

为了在渤海湾盆地辽河坳陷锦310预探井钻探前预测锦1井区古近系沙二段储集层的质量,文中应用成岩作用数值模拟技术预测了该地区沙二段的成岩阶段,综合考虑成岩作用和沉积微相对储集层孔隙度的影响,建立了孔隙度预测模型,在钻前预测了沙二段的孔隙度。结果表明,锦1井区沙二段储集层在大部分地区处于中成岩阶段A期,次生孔隙发育;在填隙物含量高达16.13％的条件下,锦310井钻前预测孔隙度和钻后实测孔隙度的绝对误差只有1.3％。由此可见,综合考虑成岩作用和沉积相的钻前储集层质量预测方法,可应用于预探井的勘探部署。  相似文献   

南堡凹陷老爷庙地区构造-沉积分析   总被引：2，自引：0，他引：2  

张翠梅  刘晓峰  苏明 《地球科学》2009,34(5):829-834

利用构造-沉积分析方法, 探讨南堡凹陷老爷庙横向背斜对东营组扇三角洲沉积体系的控制作用.通过对西南庄边界断层和老爷庙背斜的几何学解剖, 确定老爷庙背斜为西南庄断层断面弯曲控制的横向背斜.该背斜从沙河街组一段沉积期开始发育, 馆陶组沉积期叠加了NE向的走滑断层.含砾率统计发现, 含砾率高值均分布在横向背斜转折端、横向背斜和边界断层交汇控制了主水系的入口, 提供长距离输沙路径.从井-震结合剖面和古地貌图识别出横向背斜发育时期的上、下坡折位置.扇三角洲平原受上坡折控制, 发育在背斜转折端; 下坡折控制扇三角洲前缘和前扇三角洲的分界.边界断层控制的横向背斜在沉积盆地内普遍发育.横向背斜控制长距离输沙和相分配模式对砂体预测具有重要的意义.   相似文献   

鹿乡断陷C区块双阳组测井岩性识别及储层有效厚度的确定     

刘柏依  程日辉  王志文  蒋飞  赵石乐 《世界地质》2017,36(1):182-194

针对伊通盆地鹿乡断陷五星构造带油藏,提出一种适用于本区块的测井岩性识别模式及确定储层有效厚度的方法。利用包括自然伽马(吉林伽马)、普通电阻率、声波时差和自然电位曲线的综合分析,通过绘制各类曲线交会图,确定各类岩性的有效指标范围,确认出本区可识别的6种岩石类型即泥岩、粉砂岩、细砂岩、中砂岩、粗砂岩和砂砾岩。在测井解释近似的情况下,提出反推排除法,结合区域整体沉积相带分布规律和相邻井之间的测井曲线相互关系,区分细砂岩与含砾砂岩。在测井解释的基础上进行储层有效厚度研究,建立孔隙度、渗透率、含油饱和度模型,总结出岩性下限标准、物性下限标准、电性下限标准,利用建立的模型及解释图版,对本区块的39口井进行油水层校正,编制单砂层有效厚度图和单砂层岩性-微相图。  相似文献   

南盘江盆地首次发现早三叠世海生爬行动物化石   总被引：1，自引：1，他引：0  

周长勇  张启跃  黄金元  胡世学  文芠  谢韬 《地质通报》2017,36(1):168-171

首次在南盘江盆地望谟地区下三叠统罗楼组灰岩中发现了海生爬行动物化石,爬行动物化石层位相伴产出大量菊石、腕足、双壳、牙形石等,其时代属早三叠世奥伦尼克期的Spathian亚期。该发现对于研究早三叠世海洋生态复苏、海生爬行动物类群起源、早期演化具有十分重要的科学意义。  相似文献