Simulation experiment on hydrocarbon generating potential of various source rocks on the northern margin of the Qaidam Basin,Qinghai, China     

Xin Li  Dongliang Wang  Baoquan Liu  Chunling Ren  Jianying Guo  Xuefeng Su  Jian Wang 《中国地球化学学报》2008,27(4):412-419

The northern margin of the Qaidam Basin is one of the main oil-gas exploration areas in western China, where source rocks are composed mostly of Middle and Lower Jurassic dark mud shale, carbargillite and coal. A large number of subsurface and outcrop samples differing in lithology with different types of organic matter were selected for resource evaluation, research and calculation. And among them, 13 samples were used for simulation experiment on hydrocarbon generating potential of various source rocks. At first, two kinds of heating modes were compared through simulation experiment, including single temperature-step heating and continual heating. Perhaps, the process of hydrocarbon generation and expulsion occurred naturally between a close system and an open system. In addition, the first heating mode was convenient, and all its reaction products were involved in the whole thermal evolution, and the final simulation experimental results were basically in consistency with the natural evolution trend Therefore, the first heating mode was adopted and the hydrocarbon yield of every sample was worked out. According to the type and lithology of organic matter and the hydrocarbon yield of samples for simulation experiment, hydrocarbon generation and expulsion mode with three kinds of lithology and five types of source rock has been established to provide the basis for hydrocarbon generation evaluation, research and resource calculation.  相似文献   

冀中坳陷饶阳凹陷留西地区古近系沙河街组沙三上亚段沉积相与隐蔽油藏   总被引：3，自引：1，他引：2       下载免费PDF全文

张大智  纪友亮  韩春元  初丽兰 《古地理学报》2008,10(6):571-582

通过岩心观察和单井相分析,结合沉积背景资料,认为留西地区古近系沙河街组沙三上亚段发育辫状河三角洲相和湖泊相,以辫状河三角洲前缘亚相和滨浅湖亚相为主,主要发育辫状分流河道、越岸沉积、水下分流河道、河口坝、席状砂等微相。根据层序地层学基本原理,结合前人研究成果,认为本区沙三上亚段为一完整的三级层序,可划分为低位、湖侵和高位3个体系域,分别对应于沙三上亚段沉积时期的早期、中期和晚期,绘制了每个沉积阶段的沉积相图,在此基础上研究了沉积体系的平面展布特征。沙三上亚段沉积时期形成的北高南低的构造背景与辫状河三角洲近东西向展布的砂体形态相互配置,加之良好的油源供给,为后期成藏创造了条件。沙三上亚段沉积早期发育的辫状河三角洲前缘水下分流河道与河口坝砂体是主要的储集体,与沉积中期发育的烃源岩形成了十分有利的生储盖组合,具有优越的隐蔽油藏发育条件。总结了该区隐蔽油藏成藏的4种模式,确定留西地区中南部沙三上亚段沉积早期发育的辫状河三角洲前缘砂体是下一步隐蔽油藏勘探的有利目标。  相似文献   

一种新的储层孔隙成因类型--石英溶解型次生孔隙   总被引：26，自引：2，他引：26  

邱隆伟  姜在兴  陈文学  李晓红  熊志东 《沉积学报》2002,20(4):621-627

石英作为碎屑岩储层中的一种难溶组分,普遍认为它和次生孔隙的形成关系不十分密切。研究认为泌阳凹陷核桃园组储层中的碎屑石英颗粒存在明显的溶解现象,并形成以石英直接溶解型孔隙为主的储集空间特征。石英颗粒被溶解的部分在薄片中所占的范围为 2 %～ 7%者常见,高者达 8%以上,在总孔隙中所占的相对含量也多数在10 %～ 35 %之间,早成岩B期是其最主要形成期。石英溶解型次生孔隙的大量存在为碎屑岩储层中SiO₂ 胶结物及次生孔隙成因等问题的解释以及储层预测和评价提供了新的可能性。  相似文献   

Characteristics and Genetic Mechanisms of Overpressure in the Depressions of Bohai Bay Basin, China     

LIU Hu  JING Chen  JIANG Youlu  SONG Guoqi  YU Qianqian  FENG Yuelin 《《地质学报》英文版》2016,90(6):2216-2228

The distribution and genetic mechanisms of abnormal pressures in the Bohai Bay Basin were systematically analyzed. Abnormal pressures are widely developed in the Bohai Bay Basin, primarily in the Paleogene E2s4, E2s3, Es1, and Ed formations. From the onshore area of the Bohai Bay Basin to the center of the Bozhong area, the top depth of the overpressured zone in each depression increases gradually, the overpressured strata in each depression gradually move to younger formations, and the pressure structure successively alters from single-bottom- overpressure to double-bottom-overpressure and finally to double-top-overpressure. The distribution of overpressured area is consistent with the sedimentary migration controlled by the tectonic evolution of the Bohai Bay Basin, which is closely related to the hydrocarbon-generation capability of active source rocks. The overpressured strata are consistent with the source-rock intervals in each depression; the top of the overpressured zone is synchronous with the hydrocarbon generation threshold in each depression; the hydrocarbon generation capability is positively correlated with the overpressure magnitude in each formation. Undercompaction was the main mechanism of overpressure for depressions with fluid pressure coefficients less than 1.2, whereas hydrocarbon generation was the main mechanism for depressions with fluid pressure coefficients greater than 1.5.  相似文献   

二连盆地赛汉塔拉凹陷腾二段低熟油地球化学特征和油源对比     

李杰豪  侯读杰  曹兰柱  吴飘  赵喆  马潇潇 《现代地质》2021,35(2):315-325

赛汉塔拉凹陷位于二连盆地腾格尔坳陷西部,是二连盆地低熟油分布区。采用有机地球化学和生物标志物分析方法,对赛汉塔拉凹陷下白垩统腾二段低熟原油和油砂样品进行了地球化学特征和油源对比研究。赛汉塔拉凹陷腾二段低熟油具有饱和烃含量相对较低、非烃和沥青质含量相对较高的族组成特征,正构烷烃分布以前峰型为主,主峰碳为C₂₁或C₂₃,Pr/Ph低(0.29~0.59),Pr/nC₁₇ 较低(0.29~0.58),Ph/nC₁₈较高(0.57~1.37),C₂₉甾烷20S/(20S+20R)为 0.27~0.40、C₂₉甾烷ββ/(αα+ββ)为0.29~0.39,伽马蜡烷指数多为0.31~1.34,三环萜烷含量低,反映出原油生成于半咸水—咸水还原环境,生源以藻类输入为主。油源对比研究认为,赛汉塔拉凹陷腾二段低熟油有两种来源:一种是来自下伏腾一段烃源岩咸水环境成熟早期阶段生烃;另一种是来自洼槽中心低成熟的腾二段烃源岩自生自储。  相似文献   

断陷盆地缓坡带河流沉积砂体定量表征及控制因素分析:以霸县凹陷文安斜坡东营组三段为例     

张自力  朱筱敏  廖凤英  李琦  张锐锋  曹兰柱  施瑞生 《地学前缘》2021,28(1):141-154

断陷湖盆缓坡河流成因砂体是重要的油气储集单元。根据岩心观察、钻井岩/电特征并结合地震沉积学方法,分析断陷湖盆缓坡河流沉积体系和砂体时空分布特征,能为油气精细勘探提供可靠的依据。研究表明,霸县凹陷文安斜坡中部东营组三段周期性地发育4条呈NE-SW辫-曲复合型河流沉积,由河道沉积、砂坝沉积和泛滥平原沉积3种亚相以及辫状河道、曲流河道、砂质河道砂坝、泥质河道砂坝、决口扇和泛滥平原泥6种微相构成。河流展布方向与正北夹角(α)为40°~65°,河道视宽度(l)为1.47~2.64 km,主河道的视宽度(w)为0.03~0.58 km,河道带测量厚度(H)为16.0~52.0 m,主河道测量厚度(D)为8.0~23.0 m,主河道钻井解释厚度(d)为1~16.5 m,平均厚度6.5 m。断陷盆地断-坳转换期缓坡河流相沉积受控于盆地构造、气候、物源、沉积物压实及流速等多因素。边界断层差异性活动导致的盆地不均衡沉降是缓坡带河流相类型及砂体空间分布的主控因素。气候周期性变化通过流量控制了河型,调整和改造早期河道沉积物,决定了微相和砂体组合。斜坡中外带是粗粒沉积物主要卸载区,河道及河道砂坝等优势储集砂体呈条带状连片分布,斜坡内带形成的厚层泥岩限制油气垂向运移和侧向充注。斜坡中外带被油源断层切割,在油气运移路径上受晚期断层切割的厚层河道及河道砂坝是岩性-构造油气藏勘探的潜力区域。  相似文献   

断陷湖盆缓坡带古河道定量恢复方法及油气地质意义：以霸县凹陷文安斜坡东营组为例     

张自力  朱筱敏  陈贺贺  张锐锋  曹兰柱  施瑞生  谢爽慧 《高校地质学报》2021,27(5):501-514

河流沉积砂体定量表征是油田高效勘探开发的重要基础。文章综合利用定量岩心分析、测井相分析、定量地震沉积学和三维地震剖面识别方法,对霸县凹陷文安斜坡东营组古河道砂体厚度,河道（带）宽度,（满岸）河道水深等河流参数进行了定量化计算。研究表明,文安斜坡东营组发育北部苏桥、中部文安和南部长丰镇三个物源输入口,河流呈NEE-SWW向分散于文安斜坡带,其中河道带宽度（w）为1.04~2.61 km,平均宽度（wcb）为1.71 km;主河道宽度（W）为15.2~179.6 m,平均宽度（Wc）为84.4 m;主河道沉积水深（D）为1.34~5.21 m,平均水深（Dc）为3.29 m;主河道满岸水深（Dmax）为2.35~9.15 m,平均满岸水深（Dmaxa）为5.77 m;主河道沉积厚度（H）为2.15~8.32 m,平均厚度（Hc）为5.25 m,河道长度（L）为18.5~28.2 km,平均河道带长度（Lcb）为25.1 km,流向（A）为40°~65°。确定文安斜坡东营组发育辫状河沉积,斜坡东侧中外带为主要的砂岩卸载区,河流以垂向挖掘性河流为主,侧向迁移为辅,河道砂岩平面呈“条—带”状。文安斜坡西侧内带以侧向迁移河流为主,下蚀作用为辅,河道砂岩呈“席—带”状。东营组河道砂岩具有“下生上储”的有利成藏条件,具有良好的岩性、构造—岩性圈闭（油气藏）勘探前景。  相似文献   

Comment on a paper by Sibuet et al. (2016) entitled “Thinned continental crust intruded by volcanics beneath the northern Bay of Bengal”     

《Marine and Petroleum Geology》2017

  相似文献   

腐殖煤气态产物演化特征的模拟实验研究   总被引：3，自引：0，他引：3  

高岗 《沉积学报》1998,16(2):30-41

本文较详细地探讨了成熟阶段腐殖煤在加水热模拟过程中气态产物的演化特征。成熟阶段的煤仍具有相当的生烃潜力,其主要生烃阶段仍以生油为主,生气相对较少。生油高峰之后由于液态产物的大量热裂解才开始进入气态烃的大量生成阶段。由于地质条件下煤中的可溶有机质十分丰富,在高演化阶段由可溶有机质进一步裂解是煤成气的重要来源。非烃主要形成于早期阶段。成熟煤生成的气态烃中甲烷为之主要成分,非烃中H₂为主,其次为CO₂,甲烷的碳同位素值明显低于乙烷,而乙烷和丙烷的碳同位素值差别较小,并且随演化程度的增加各气态组分的碳同位素值差别愈来愈小。  相似文献   

磁暴二倍法预报唐山7.8级地震   总被引：5，自引：0，他引：5       下载免费PDF全文

张铁铮 《地震工程学报》1998,20(2):29-35

磁暴二倍法预报地震的依据是,应变能在运移过程中导致地壳膨胀和压缩形成一个周期,在时间上呈有二倍关系．唐山７．８级地震是我国７０年代最大地震,用磁暴二倍法推出有４组磁暴能对应这次地震．每组磁暴前后都发生了地震,由于这些地震释放的剩余能量在聚积过程中,地壳发生膨胀和压缩,地磁场就受到影响形成了磁暴．因此磁暴与地震能量变化有相关性．可见,磁暴二倍法可以预报地震．  相似文献