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61.
通过镜下观察,宋芳屯油田扶杨油层孔隙类型较多,以粒间孔为主。细管压力曲线上看,曲线较陡,分选差,孔隙结构特征参数总体上较差,与孔隙度、渗透率有一定的关系,大的孔隙对渗透率的贡献最大。扶杨油层的孔隙结构较复杂主要由于成岩作用影响,压实作用使孔隙空间显著缩小,胶结作用和自生粘土矿物生长使孔隙进一步缩小和复杂化,后期的溶蚀作用使孔隙空间增加。  相似文献   
62.
讨论分析数值模拟技术在海坨子油田开发调整研究中的思路和方法,采用美国Landmark公司VIP2003.4版本数值模拟软件包进行模拟研究,通过参数准备,静、动态拟合,模拟出海坨子油田海S9—11井组1—9砂组各小层剩余储量大小及不同阶段流体饱和度分布,结合可视化技术形象描述了海坨子油田剩余油变化规律及潜力区,在此基础上预测不同井网加密方式开发指标,并优选出最佳方案,为海坨子油田下步开发调整提供了重要依据,取得了较好的效果。  相似文献   
63.
Two widely-used techniques to estimate the volume of remaining oil and gas resources are discovery process modeling and geologic assessment. Both were used in a recent national assessment of oil and gas resources of the United States. Parallel estimates were obtained for 27 provinces. Geological-based estimates can typically see into areas not available to discovery process models (that is areas with little or no exploration history) and thus, on average, yield higher estimates. However, a linear relation does exist between the mean estimates obtained from these two methods. In addition, other variables were found in a multiple regression model that explained much of the difference. Thus, it is possible to perform discovery process modeling and adjust the estimates to yield results that might be expected from geological-based assessments.  相似文献   
64.
保存条件是中扬子地区页岩气富集的关键因素之一,宜地2井是中扬子寒武系页岩气发现井,通过对该井全井段岩芯裂缝古流体的地球化学分析,探讨了寒武系古流体成因和对水井沱组页岩气保存条件的指示意义。结果认为:① 覃家庙组膏岩层之上方解石脉缺少Fe2+、Mn2+,且δ13C和δ18O值较围岩偏负,指示其形成于氧化的环境,石牌组方解石脉δ13C偏负,黄铁矿脉δ34S值与膏盐相似,表明其成因与TSR密切相关;水井沱组脉体δ13C和δ18O与围岩相似,形成于封闭的环境。② 方解石脉包裹体群SO42-、Ca2+、Mg2+含量整体上由覃家庙组向上向下分别递减,钠氯系数以水井沱组最低,整体上向上升高,表明覃家庙组是高盐度卤水的主要来源,水井沱组受外来流体影响弱;包裹体水溶液δD和δ18O也指示娄山关组、石牌组方解石脉成因分别与大气水、TSR相关。③ 古流体地球化学研究表明宜昌地区页岩气保存条件整体较好,页岩气散失的主要通道是垂直裂缝,页岩气保存条件好与膏盐盖层发育、后期构造破坏弱、脉体对裂缝的及时封闭以及白垩系盖层等因素密切相关。  相似文献   
65.
西江主洼是珠江口盆地一个低勘探程度洼陷,油气差异聚集特征明显,但其机理不清。本文在断陷盆地油气成藏理论指导下,利用研究区地质、地球物理和地球化学等资料,开展了烃源岩、断盖组合、储集体系和运聚模式等方面的研究。结果表明,裂陷期沉降、沉积中心有序迁移,造成主力烃源岩自东向西由文四段迁移至文三段、文一+二段,控制东、西部油气差异分布。恩平组区域性泥岩发育且晚期断裂缺乏,导致油气纵向上更易聚集于下构造层;区域泥岩减薄尖灭或晚期断裂切开盖层的区域,上构造层有一定油气分布。"源-汇"类型从宏观上控制储层优劣,影响下构造层油气富集程度;"仓储"运移是控制上构造层油气规模聚集的主要模式。下构造层古近系应作为重点部署方向,东部围绕文四段、西部围绕文三段、文一+二段烃源岩构成的含油气系统展开;上构造层勘探需关注珠海组,在隆起周边寻找具备"仓储"运移模式的有利区带。  相似文献   
66.
The American whaling industry rose from humble beginnings off Long island to become an international giant. In its peak year, 1846, 735 ships and 70,000 people served the industry. As whale stocks and reserves decreased, whalers were forced to go farther and farther from their New England home ports. Voyages became longer, and risks on required return-on-investment became higher. The easy money of Atlantic and Pacific whaling was no more: the only remaining profitable ventures were to Arctic and Antarctic waters. Many ships returned empty, if at all. in 1871, most of the Arctic whaling fleet was crushed by early winter ice and lost. This calamity, in conjunction with the long-term diminishing whale stocks, the diversion of investment capital to more profitable ventures, and the discovery, development, and refinement of abundant petroleum crude oil, struck the death blow to the American whaling industry. By 1890, only 200 whaling vessels were at work, and by 1971, no American commercial whaling ship sailed the world's oceans.It is apparent that no single event caused the final, rapid decline. However, a single calamity, in an already stressed industry, that was self-insured and commercially interlinked, precipitated the end. Today's American petroleum industry, although adopting some principles of the American whaling industry, also has embraced other activities such as work process reengineering and customer alliances, which may preempt, or postpone, a similar catastrophic demise.  相似文献   
67.
以吉林省境内红星构造带(已发现油田)和杨柳青构造带(未发现油田)为试验区,首先利用地震地层学方法,研究间接参数特征,确定有利相带和有效圈闭,并在有效圈闭上选择了39个2×2cm时窗。在时窗内提取与地震波动力学有关的信息,即频率、振幅、频谱能量等,然后对这种信息进行统计计算,获得振幅方差等九个参数并对其进行综合分析,从已知油气藏出发,对未知圈闭油气状况进行了三级预测,指出了最有利的勘探靶区。  相似文献   
68.
The black shale formed under anoxic conditions usually contains high concentrations of many metals. Weathering of such black shale might cause the emission of many metals. Moreover, soils derived from black shale (SBS) are believed to be affected by black shale weathering. In recent years, many studies such as Lee et al. (2002), Woo et al. (2002), Fang et al. (2002), Pasava et al. (2003), and Peng et al. (2004) have approached the heavy metal contaminations of SBS, but systematical geochemical study is rare. Presently, the SBS and its corresponding black shales (CBS) were both sampled from central Hunan (China), and analyzed for a large number of elements, using an Elan6000 ICP-MS/AES machine at Guangzhou Institute of Geochemistry, CAS. In this paper, some preliminary results are reported. The analytical results show that the SBS in central Hunan contains very high concentrations of heavy metals such as Co, Cu, Hg, Mo, Pb, Zn, U, Th, Sb, T1, Cd, Cr, Sc, V, Sn, As, Se, and Ni.  相似文献   
69.
Naturally acidic drainage associated with pyritic black shale has been observed in many locations in the Yukon Territory. While not necessarily linked to known mineral deposits, most of these natural acid rock drainage occurrences show elevated dissolved concentrations of trace elements, especially zinc, nickel, copper, cadmium and arsenic. Based on field observations, microbial investigation, chemical analyses and geochemical modeling, the fate and transport of potentially deleterious elements at two natural acid drainage occurrences with slightly different settings are examined. The Macintosh Creek is a small, acidic stream (pH 2.98-3.40), 2 km long, located in the Macmillan Pass area of east-central Yukon amidst known sedimentary exhalative massive sulfide mineralization but remains undisturbed by exploration activities. Its trace metal content is apparently derived from groundwater discharges, which gave as much as 5.0, 2.5, 0.7, 0.13 and 0.03 mg/L ofZn, Ni, Cu and As, respectively. Interaction and sorption reactions with algal mats, biofilms and iron oxyhydroxides appear to be the dominant mechanisms attenuating aqueous contaminant transport along the stream. Cryogenic precipitation further consolidates the ferricrete formation and reduces the mobility of the sorbed metals. The tributaries of the Engineering Creek along the Dempster Highway in northern Yukon drain through a series of dolomite, phyllite, argillite, limestone, black shale, sandstone and conglomerate with no known concentration of mineralization. In this area, the water chemistry fully reflects the local geology with acidic streams invariably associated with black shale occurrences. Groundwater seeps in the headwaters area of the km-180 Creek completely enclosed in black shale gave pH 3.0 and as much as 148, 39, 2.9 and 9.1 mg/L of Zn, Ni, Cu and As, respectively. Sorption with iron oxyhydroxide and organic matter appear to dominate the attenuation of contaminant transport along the stream. However, once entered into carbonate-dominated terrains, secondary carbonate minerals exercise additional geochemical control on the local water chemistry as a result of neutralization.  相似文献   
70.
In the process of steam stimulation exploitation of viscous crude oil, the injected water, at high temperature and under high pressure, reacts intensively with the host rock. This kind of water–rock interaction in Liaohe Shuguang Oil Field was studied on the basis of analysis of water composition changes, laboratory experiments, mineral saturation indices analysis, and mass balance calculation. Compared with the injected water, the changes of the composition of discharged water are mainly the distinct decrease of pH, Na+, SiO2 and Cl, as well as the increase of K+, Ca2+, Mg2+, SO 4 2− and HCO 3 . Laboratory experiments under field conditions showed: the dissolution sequence of minerals quantitatively is quartz>potassium feldspar>albite, and the main change of clay minerals is the conversion of kaolinite to analcime. Mass balance calculation indicated during the process of steam stimulation, large quantities of analcime are precipitated with the dissolution of large amounts of quartz, kaolinite, potassium feldspar, and CO2. These results correlated very well with the experimental results. The calculated results of Liaohe Shuguang Oil Field showed that during the steam stimulation for viscous crude oil, the amounts of minerals dissolved (precipitated) are huge. To control the clogging of pore spaces of oil reservoirs, increased study of water–rock interaction is needed.  相似文献   
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