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41.
42.
基于传统吸附烃概念的烃类检测新技术 总被引:5,自引:1,他引:4
烃类是地表油气地球化学勘查地下油气藏的直接指标.目前我国油气化探中常用的酸解烃法检测出的烃类,不应定义为"吸附烃",它是介质吸收的产物,属结合态烃类,应定义为"吸收烃".地表酸解烃异常十分稳定,重现性好,能够很好地证明地质历史上曾经有过的烃类运移过程,但在反映目前深部油气信息方面具有多解性.针对酸解烃法的弱点,依据烃类垂向运移理论和物质吸附作用原理,自行设计开发、研制了一套吸附烃脱气装置,建立了土壤吸附烃提取新技术和检测方法.该方法有利于在近地表获取油气系统的动态信息,强化烃类测量法对其信息源的探测,可以提高地表油气化探预测油气分布的成功率. 相似文献
43.
Research Advances and Exploration Significance of Large-area Accumulation of Low and Medium Abundance Lithologic Reservoirs 总被引:1,自引:1,他引:0
In recent years, a series of large low and medium abundance oil and gas fields are discovered through exploration activities onshore China, which are commonly characterized by low porosity-permeability reservoirs, low oil/gas column height, multiple thin hydrocarbon layers, and distribution in overlapping and connection, and so on. The advantageous conditions for large-area accumulation of low-medium abundance hydrocarbon reservoirs include: (1) large (fan) delta sandbodies are developed in the hinterland of large flow-uncontrolled lake basins and they are alternated with source rocks extensively in a structure like "sandwiches"; (2) effective hydrocarbon source kitchens are extensively distributed, offering maximum contact chances with various sandbodies and hydrocarbon source rocks; (3) oil and gas columns are low in height, hydrocarbon layers are mainly of normal-low pressure, and requirements for seal rock are low; (4) reservoirs have strong inheterogeneity and gas reservoirs are badly connected; (5) the hydrocarbon desorption and expulsion under uplifting and unloading environments cause widely distributed hydrocarbon source rocks of coal measures to form large-area reservoirs; (6) deep basin areas and synclinal areas possess reservoir-forming dynamics. The areas with great exploration potential include the Paleozoic and Mesozoic in the Ordos Basin, the Xujiahe Formation in Dachuanzhong in the Sichuan basin, deep basin areas in the Songliao basin etc. The core techniques of improving exploration efficiency consist of the sweetspot prediction technique that focuses on fine characterization of reservoirs, the hydrocarbon layer protecting and high-speed drilling technique, and the rework technique for enhancing productivity. 相似文献
44.
LIU Luofu HUO Hong GUO Yongqiang CHEN Lixin LI Shuangwen ZHAO Yande LI Yan WANG Ping CHEN Zhijun 《中国地球化学学报》2008,27(1):1-8
The results presented in this paper indicated that the carbazole-type compounds have high thermal stability and also show stability in oxidation and bio-degradation. This kind of compounds still has high concentrations and a complete distribution in the analyzed dry asphalt samples, showing that they are particularly useful in the study of hydrocarbon migration of the paleo-pools. The difference in the contents of nitrogen compounds in the Silurian dry asphalts from the Awati, Tabei and Tazhong areas is attributed to the difference in the extent of oxidation and (or) bio-degradation for the areas; the Awati and Tabei areas underwent relatively strong oxidation and bio-degradation. During the first stage of hydrocarbon pool formation in the Silurian system in the Tazhong and Tabei areas of the Tarim Basin (at the end of the Silurian period) and at the second stage in the Awati area (in Permian), the hydrocarbons experienced a long-distance migration. 相似文献
45.
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
46.
Formation Dynamics and Quantitative Prediction of Hydrocarbons of the Superpressure System in the Dongying Sag 总被引:1,自引:0,他引:1
Based on the theory of formation dynamics of oil/gas pools, the Dongying sag can be divided into three dynamic systems regarding the accumulation of oil and gas: the superpressure closed system, the semi-closed system and the normal pressure open system. Based on the analysis of genesis of superpressure in the superpressure closed system and the rule of hydrocarbon expulsion, it is found that hydrocarbon generation is related to superpressure, which is the main driving factor of hydrocarbon migration. Micro fractures formed by superpressure are the main channels for hydrocarbon migration. There are three dynamic patterns for hydrocarbon expulsion: free water drainage, hydrocarbon accumulation and drainage through micro fissures. In the superpressure closed system, the oil-driving-water process and oil/gas accumulation were completed in lithologic traps by way of such two dynamic patterns as episodic evolution of superpressure systems and episodic pressure release of faults. The oil-bearing capacity of lithologic traps is intimately related to reservoir-forming dynamic force. Quantitative evaluation of dynamic conditions for pool formation can effectively predict the oil-bearing capability of traps. 相似文献
47.
Subtle traps or oil pools have become an important exploration play in the Dongying Depression, Bohai Bay Basin, east China. Despite recent successes in exploration, the formation mechanisms of subtle traps are still not well understood. The majority of subtle oil pools in the Dongying Depression are developed in the middle interval of the Es3 Member of the Paleogene Shahejie Formation with the subtle traps being primarily of lenticular basin-floor turbidite sands encompassed in mudstones. Oil in the subtle traps was previously thought to have migrated directly from the surrounding source rocks of the same formation (Es3). Detailed geochemical investigation of 41 oils and 41 rock samples from the depression now indicates that the oils from the subtle traps cannot be correlated well with the surrounding Es3 source rocks, which are characterized by high Pr/ Ph (〉1), low Gammacerane/C30hopane, representing a freshwater lacustrine setting. In contrast the oils features low Pr/Ph (〈1) and relatively high Gammacerane content, showing a genetic affinity with the underlying Es4 source rocks, which also have the same qualities, indicating a brackish lacustrine setting. Oils in the Es3 subtle traps are probably derived from mixed sources with the contribution from the upper Es4 source rocks predominating. Therefore unconventional oil migration and accumulation mechanisms need to be invoked to explain the pooling of oils from the ES4 source rocks, which probably came through a thick low interval of the Es3 source rocks with no apparent structural or stratigraphic pathways. We suggest that the subtle oil migration pathway probably plays an important role here. This finding may have significant implications for future exploration and the remaining resource evaluation in the Dongying Depression. 相似文献
48.
49.
论油气成藏与金属成矿的关系及综合勘探 总被引:2,自引:0,他引:2
从油气藏及金属矿藏的来源、运移、成藏/成矿等方面对油气成藏和金属成矿之间的关系进行了论述,指出油气藏和沉积金属矿藏均来自于相同的烃源岩/矿源层。一些金属(铀、黄铁矿等)的存在,有可能对有机质向烃类的转化起到了积极的催化作用,而烃类中的有机酸对金属元素具有溶解、螯合作用,有利于金属元素随烃类和成矿流体的析出。烃类和成矿流体在水-油-岩共存体系,在近乎相同的运移机制和路径中,能够一起溶解、萃取其路径上的金属元素,有利于金属元素的运移。油气与成矿流体可以在圈闭中聚集、成藏或者由于物理化学条件的变化,金属矿物独立沉淀成矿。油气与金属的成藏/成矿在时间和空间上也具有某些相似性。因此油气成藏和金属成矿具有非常密切的关系,有利于对二者进行综合勘探和利用,具有非常重要的现实意义。 相似文献
50.
为深入分析南堡凹陷周边地区碳酸盐岩油气成藏机理,笔者通过对区内碳酸盐岩的薄片鉴定、化学分析、烃源岩分析、物性分析、铸体压汞等实验测试和分析.结果表明,区内碳酸盐岩不具备生油能力,其油源为南堡凹陷古近系生油岩,且古近系生油岩生油母质较好、成熟度高、厚度大;碳酸盐岩基质孔隙度差,晶间孔欠发育,早期裂缝基本被充填完全,晚期构造裂缝为油气运移和聚集的主要空间;岩溶发育垂向分带不明显,溶蚀孔洞孤立且连通性差;区内主要发育有4类盖层,且储盖组合良好,发育有不整合油藏和构造块状油藏两种油气藏类型. 相似文献