渤海湾地区Z油田沙一下生物灰岩油藏裂缝特征及其形成机理          下载免费PDF全文

严锐涛  曾联波  赵向原  廖宗湖  陈敏政 《地质科学》2016,(2):484-493

以渤海湾地区Z油田沙一下生物灰岩油藏为例, 利用岩心、薄片及成像测井等资料, 对天然裂缝特征及控制因素进行研究, 并对裂缝的成因机理进行了分析.研究表明, Z油田沙一下生物灰岩储层主要发育构造裂缝及成岩裂缝两种类型, 其中构造裂缝又分为剪切裂缝及扩张裂缝两类; 大多数构造裂缝为高角度缝, 主要方位为北东-南西向、北西-南东向及近东西向; 裂缝纵向高度一般小于170 cm, 裂缝平面长度主要分布在35 m以内, 裂缝开度主要在100 μm以内; 裂缝的发育受岩性、岩层厚度、断层等地质因素控制.该区构造裂缝主要在始新世-渐新世裂陷中后期北西-南东向引张应力场及东营末期北东东-南西西向反转挤压应力场两期构造应力作用下形成, 其中早期主要形成北东-南西向的正断层型裂缝, 晚期主要形成北东-南西向、北西-南东向的剪切裂缝及近东西向扩张裂缝.  相似文献   

Two-dimensional reactive transport modeling of the alteration of a fractured limestone by hyperalkaline solutions at Maqarin (Jordan)     

《Applied Geochemistry》2016

Two-dimensional reactive transport modeling of the Maqarin Eastern Springs site, a natural analogue for the alteration of a fractured limestone by high-pH Portland cement waters, has been performed using the CrunchFlow code. These 2D calculations included transport by advection–dispersion–diffusion along a single fracture and diffusion in the wall rock. Solute transport was coupled to mineral dissolution and precipitation. A limited sensitivity analysis evaluated the effect of different values of primary mineral surface areas, flow velocity and sulfate concentration of the inflowing high-pH solution.Major secondary minerals include ettringite–thaumasite, C–S–H/C–A–S–H and calcite. C–S–H/C–A–S–H precipitation is controlled by the dissolution of primary silicates. Ettringite precipitation is controlled by diffusion of sulfate and aluminum from the wall rock to the fracture, with aluminum provided by the dissolution of albite. Calcite precipitation is controlled by diffusion of carbonate from the wall rock. Extents of porosity sealing along the fracture and in the fracture-wall rock interface depend on assumptions regarding flow velocity and composition of the high-pH solution. The multiple episodes of fracture sealing and reactivation evidenced in the fracture infills were not included in the simulations. Results can qualitatively reproduce the reported decrease in porosity in the fractures and in the wall rock next to the fractures. Instances of porosity increase next to fractures caused by carbonate dissolution were not reproduced by the calculations.  相似文献   

塔里木盆地麦盖提斜坡西段石炭系生屑灰岩段旋回划分及意义   总被引：2，自引：0，他引：2  

张惠良  张荣虎  李勇  陆俊明  王月华 《地层学杂志》2008,32(1):91-98

从露头剖面及钻井岩芯、电性特征入手,结合区域地质背景认为:麦盖提斜坡西段石炭系生屑灰岩段横向展布相对稳定,夹在上下两套泥岩(或膏质泥岩)之间,呈连续沉积过渡,电测曲线为低伽玛值、高电阻率值,形态总体呈箱形。生屑灰岩段在岩性、电性特征上均具明显的成段性,自下而上具有四次旋回性(相当于五级层序)。Ⅰ旋回层主要为灰质云岩夹膏质灰岩、泥质云岩,电阻率、自然伽玛曲线呈漏斗型,与下伏及上覆地层均呈突变过渡;Ⅱ旋回层主要为含泥灰岩、泥晶灰岩,自然伽玛、电阻率曲线均呈鼓型、箱型特征,与上覆地层呈突变过渡,电阻率曲线幅值相对较高;Ⅲ旋回层主要为泥晶灰岩、泥质灰岩、云质灰岩夹生屑灰岩,电阻率、自然伽玛曲线呈低幅度锯齿型,自然伽玛幅度相对较高,电阻率幅值相对较低,与上覆地层均呈渐变过渡;Ⅳ旋回层以白云岩、灰质云岩为主,电阻率及自然伽玛曲线呈复合钟型特征,与上覆地层均呈突变接触。地层精细划分对比有助于更好地认清生屑灰岩段在纵横向的变化规律,进一步突出有利储集区(琼002—群6井)及有利储集层段(Ⅳ旋回层),为下一步的勘探夯实理论基础。  相似文献   

A new hangingfly (Insecta,Mecoptera, Bittacidae) from the Purbeck Limestone Group (Lower Cretaceous) of southern England and a review of Cretaceous Bittacidae     

《Cretaceous Research》2016

Rapid radiation of the Bittacidae during the Jurassic resulted in high diversity within this family of Mecoptera. More than 40 species within 23 genera have been described from this period. However, around the end of the Jurassic the abundance and diversity of Bittacidae decreased and only seven species in five genera are known to date from the Cretaceous. A new specimen from the basal Cretaceous of England, Tytthobittacus jarzembowski sp. nov., described here, represents the eighth species and the second fossil representative of this family from the European Cretaceous. This hangingfly belongs to an extant and relictual genus previously known only from Australia. The paper also includes a review of all known Cretaceous bittacids and a re-examination of European species Antiquanabittacus nanus Petrulevičius and Jarzembowski, 2004.  相似文献   

山西兴县关家崖剖面马五_5亚段核形石灰岩特征及成因     

李百强  王起琮  宁博  王妍  靳程光  石堃  刘佳玮  赵克里  孟刘  闫佐 《海相油气地质》2016,(2):57-64

在观察兴县关家崖野外露头剖面马五_5亚段核形石灰岩岩性特征的基础上,进行了薄片镜下鉴定,开展了全岩X衍射,主、微量元素,锶和碳、氧稳定同位素及有机碳分析。研究结果表明,核形石灰岩形成于开阔海环境,准同生阶段核形石发生重结晶作用,浅埋藏期压实作用使巨晶方解石呈镶嵌接触并产生压力双晶纹;马五_5亚段底部核形石灰岩形成于海平面上升过程,未受早期淡水溶蚀;马五_5亚段顶部核形石灰岩形成于海平面下降过程,明显受早期大气淡水淋滤与溶蚀作用影响;在中—深埋藏阶段受地下热液影响,在水-岩作用过程中发生了同位素交换及有机质成熟及排烃作用。该套核形石灰岩的发现,明确了马五_5亚段形成于开阔海环境,这对于马家沟组烃源岩的研究具有参考意义。  相似文献   

微生物碳酸酐酶对石灰岩的溶蚀驱动作用研究   总被引：12，自引：4，他引：8  

余龙江  吴云  李为  曾宪东  付春华 《中国岩溶》2004,23(3):225-228

来源于西南几个不同类型岩溶地区土壤样品分离出来的微生物菌株中,有很多能够产生分泌胞外碳酸酐酶。以一株编号为GLCa102的菌株为代表,模拟岩溶自然环境条件,研究其胞外碳酸酐酶对灰岩的溶蚀驱动作用。结果表明微生物碳酸酐酶能使灰岩溶出的导电离子总量和[Ca2+ ]提高40%以上,从而对灰岩有显著的酶促溶蚀驱动作用。本研究表明微生物碳酸酐酶在生物岩溶中有重要的作用和地位,同时为深入研究生物对石灰岩的溶蚀作用提供了一定的科学依据。   相似文献   

Microstructural weathering of sedimentary rocks by freeze–thaw cycles: Experimental study of state and transfer parameters     

Alice Saad  Sylvine GuédonFrançois Martineau 《Comptes Rendus Geoscience》2010,342(3):197-203

The frost sensitivity of a rock is resulting from the combined action of processes linked to porous network characteristics (state parameters) and to the way water flows into this porous network (transfer parameters), our study was thus about the influence of these parameters on frost weathering of rocks. Sedimentary rocks often found on buildings (limestone and sandstone) and consequently submitted to temperature variations have been selected. State and transfer parameters have been measured for sample characterization and the follow-up of weathering during freeze–thaw cycles. The coupled influence of a state parameter (dynamic modulus of elasticity) and a transfer parameter (water permeability), i.e. between rock skeletal strength and voids connection, has thus been discussed.  相似文献   

江苏船山石灰石矿床沉积环境          下载免费PDF全文

李学娣  刘海英 《江苏地质》2011,35(1):22-27

根据每组石灰石中都含有大量的海洋沉积窄盐度生物及藻类化石,推断船山矿床为浅海碳酸盐沉积;从每组石灰石的粒度、颜色、结构构造,推断出该矿床在形成过程中有两次大规模海侵,两次沉积中断.沉积环境的变化决定了石灰石的质量,氧化环境罩形成的石灰石颜色较浅较纯可作为熔剂,还原环境里形成的石厌石颜色较深,有机质含龄高只能作为水泥原料.  相似文献   

四川旺苍双汇下二叠统茅口组眼球状石灰岩成因分析   总被引：3，自引：1，他引：2  

刘杰  李蔚洋  何幼斌 《海相油气地质》2011,16(1):63-67

四川旺苍双汇眼球状石灰岩主要分布在下二叠统茅口组的下部、中部及顶部.累计厚度102.77m,占茅口组厚度的53.27%.眼球体(瘤体)为较纯的碳酸盐岩,占全岩的40%-50%;眼皮(基质)为泥质含量较高的碳酸盐岩,条带状绕瘤体分布.瘤体和基质的原始沉积物分别形成于开阔台地环境和局限台地环境;差异压实和差异压溶作用使层状...  相似文献   

Failure and flow development of a collapse induced complex landslide: the 2005 Kuzulu (Koyulhisar, Turkey) landslide hazard   总被引：1，自引：0，他引：1  

Işık Yilmaz  Tülay Ekemen  Mustafa Yildirim  İnan Keskin  Gül Özdemir 《Environmental Geology》2006,49(3):467-476

Koyulhisar located in a slope of hilly region and constructed in the side of a mountain along the North Anatolian Fault Zone is frequently subject to landslides. A catastrophic landslide occurred on the morning of 17 March 2005 in the North of the Kuzulu district of Koyulhisar (Sivas, Turkey). This landslide caused widespread loss of life, and damage to buildings, and lifelines. Fifteen people were dead and five were injured, 21 houses and a minaret were covered and damaged severely. The case study presented in this paper describes and analyses the results of the detailed surveys of an interesting landslide in Kuzulu district of Koyulhisar (Sivas, Turkey), based on field and laboratory measurements and monitoring of the slide area. Landslide initiated as a collapse, and developed into debris avalanches in the valley. This phenomenon caused a disaster in the Kuzulu district. The importance of this landslide in particular has been recognized both in terms of its consequence for the people and structures and in terms of its role in allowing an understanding of process and properties of landslide triggered by a collapse in limestone karst. In view of the potential for such events to occur again in this area and environs, understanding of the failure mechanism is very crucial.  相似文献