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961.
四川盆地下二叠统白云岩及古岩溶的形成与峨眉地裂运动的关系 总被引:1,自引:0,他引:1
四川盆地下二叠统中次生白云岩及古岩溶是下二叠统主要的非构造圈闭储层之一。该文通过对白云岩的地球化学特征和古岩溶特征的研究,论述了白云岩和古岩溶的形成与分布规律同峨眉地裂运动的关系,以及大中型裂缝圈闭与峨眉地裂运动的关系,为油气的勘探与开采提供了依据 相似文献
962.
云南思茅—景谷地区有两类储集层:碎屑岩储集层和碳酸盐岩储集层,其中碎屑岩储集层要优于碳酸盐岩储集层。孔隙类型主要为次生溶孔,偶见剩余原生粒间孔。它们的储集性能基本上属低孔渗性储集层,强烈的压实作用、压溶作用、胶结作用、充填作用、碳酸盐化作用及重结晶作用是导致该区储集层孔渗性差的主要原因。但在有利的构造部位有可能找到孔渗性较好的区块。文中还论证了地表样品中识别埋藏古溶蚀的标志。 相似文献
963.
Application of carbazole compounds in study of hydrocarbon migration 总被引:11,自引:0,他引:11
964.
澧水流域暴雨洪水的初步研究 总被引:1,自引:0,他引:1
根据澧水流域多年实测水文气候资料的历史记载特征值,阐明了影响暴雨洪水发生发展的主导因素,并以暴雨特性为主要条件,将暴雨洪水分为四类,同时着重分析了洪水的组成与遭遇,以及暴雨洪水的基本特性。 相似文献
965.
该文利用油层温度和井温资料建立了江汉盆地拖市现代地温场分布,并估算了大地热流;采用镜质体反射率积分法计算了两期古地温梯度;用均一法实测硬石膏包裹体捕获古温度数据。结果表明,不同时期的热演化反映区域构造活动具有从东北向西南迁移的规律。根据热历史与成岩及构造演化之间的关系,讨论了导致该区域储层致密的主要因素硬石膏的充填与沉淀特征。 相似文献
966.
The chief aim of the present work is to investigate the controversy origin of natural gas in the Ordos Basin by using the
hydrocarbons of oil water. New evidence has been found: There is relatively high content of light hydrocarbons and low content
of heavy components in the hydrocarbons fraction of oil water in the middle gas field of the Majiagou Formation, Ordovician
reservoir. The hydrocarbons of oil water in Well Shan 12 and Well Shan 78 have relatively high abundance of tricyclic terpane.
Tricyclic terpane/hopane of the two samples are 1.48 and 0.36, respectively. They also show that pregnane and hompregnane
are in relatively high abundance with lower hopane/sterane ratio. Pr/Ph is less than 2.0. These characteristics reflected
the source input of marine carbonate sedimentary environment. In contrast, the hydrocarbon of Well Shan 81 is lack of tricyclic
terpane series and pregnane. It has a high hopane/sterane ratio and Pr/Ph is 3.27. These parameters are typical character
of terrestrial organic matter. Furthermore, the hydrocarbons of oil water in Well Shan 37 and Well Shan 34 is between the
two typical situations. They have little content of tricyclic terpanes. They may be derived from a mixing source of marine
carbonate and terrestrial organic matter input. Similarly, the maturity parameters approve this suggestion. The samples of
Well Shan 12 and Well Shan 78 which derived from marine carbonate have relatively high maturity and samples derived from terrestrial
organic matter have lower maturity. The maturity of the hydrocarbons of mixing source is between these two situations. The
suggestion coincides with the geological background and source rocks distribution. 相似文献
967.
Partition coefficient difference of benzocarba-zole isomers between oil, water and mineral phase makes them auseful indicator to quantify petroleum migration distance. Because of their nitrogen-heteroatom andannelated aromatic cycles they are generally regarded asbeing more resistant and the effects of biodegradation ontheir concentrations and distributions have not previouslybeen investigated. Reservoir extracts from three wells lo-cated in the Leng43 block of the Liaohe Basin were analyzed to investigate their occurrence and the effect of biodegrada-tion. Both hydrocarbon biomarkers and benzocarbazole isomers show systematical changes with the increase extent of biodegradation in study columns. Carbazole compounds may be biodegraded in a similar way to that observed in aliphatic and aromatic hydrocarbons. The distance from oil water contact is a primary control factor for biodegradation. The concentrations of benzocarbazole isomers show a slight increase in the upper part of the columns then a sharp de-crease towards oil water contact (OWC). Among three iso-mers benzo[a]carbazole seems more susceptible to biode-gradation than other two isomers and benzo[b]carbazole has higher ability to res ist bacterial attack. Benzo[b]carba-zole/benzo- [a]carbazole ratios can sensitively indicate the degree of biodegradation and the benzocarbazole index (BCratio) cannot be directly used as a migration indicator inbiodegraded oils. 相似文献
968.
ZHU Xiaomin ZHONG Dakang ZHAO Chenglin GU Jiayu WANG Zhaoming ZHOU Xinyuan 《科学通报(英文版)》2002,47(Z1):28-33
Based on the pore cast and cathodolumines-cence thin sections, diagenesis process, source rock matura-tion history, structural evolution and reservoir qualitycharacteristics, the points of view that the porosities of Pa-leozoic clastic eureservoirs in the platform of the Tarim Ba-sin are mainly secondary, and the dissolution plays anunignorable role in the formation of eureservoirs, are putforward. In this paper, a series of criteria for the recognitionof the secondary porosities, the occurrence extent and classi-fication of secondary porosity are introduced, and threekinds of dissolution mechanism—the aluminosilicate dis-solution, the silicon dioxide dissolution and the carbonatedissolution—to generate the secondary porosity are comeup with. The formation, distribution, preservation and dis-appearance of eureservoirs are controlled by the paleo-structural framework and evolution, and hydrocarbon fillingand discharging. Paleostructural framework manipulate themigration path and direction of the acid fluid so as to deter-mine the position and extent of the dissolution. Paleostruc-ture highs and continuous paleouplifts are in favor of devel-oping the secondary porosity. The hydrocarbon filling madethe secondary porosities preserved and the hydrocarbondischarging let the secondary porosities filled by later calciteor quartz overgrowth cements. Paleostructure highs andcontinuous paleouplifts during the maturation period ofCambrian, Ordovician and Carboniferous source rocks(corresponding to S, P and K) are main areas for eureservoirs developing. 相似文献
969.
970.
三万年来山西临汾盆地古地理环境的变迁 总被引:3,自引:0,他引:3
通过对临汾盆地中一个地层剖面、4个50m深钻孔中沉积物样品的粒度、粘土矿折、孢粉等第一手资料的分析,详细讨论了该盆地三万年来气候、水文、植被及沉积环境的特征、演变,重建了该盆地晚更新世以来的地理环境。 相似文献