节点文献
长庆探区低渗透油层地化录井评价方法及其应用研究
Geochemical Logging Evaluating Methods and Its Applying Research of Low Permeability Reservoir in Changqing Prospect Area
【作者】 邢立;
【导师】 刘建朝;
【作者基本信息】 长安大学 , 矿物学、岩石学、矿床学, 2008, 硕士
【摘要】 近年来,石油资源的日趋紧张,石油勘探开发的领域也在不断地扩大和延伸。同时,面临的勘探对象也更加复杂,发现新的油(气)藏(田)的技术难度也越来越大。低渗透油气资源在所发现的油气资源中所占的比例成逐年增加的趋势。低渗透岩性油气藏(田)具有隐蔽性强、四性关系不典型、油水关系比较复杂等特点,因而,运用常规的地质录井、测井等技术手段在发现和评价低渗透油气层(藏)常常会遇到一些技术困难。地球化学录井技术是在二十世纪八十年代末至九十年代初,随着有机地球化学检测技术的发展和完善,并结合油气勘探生产的技术需求,人们将一些能够快速检测储层中油气的测试技术应用于随钻录井工作,而逐步形成和完善起来的一项矿场路径技术。地化录井技术包括了用于油气定量与定性检测的诸多测试技术—如储岩热解、气相色谱、定量荧光、紫外光谱、红外光谱等等。地化录井技术的特点是能够直接快速地获得储集岩所含油气的数量和组成性质方面的准确信息,因而,不受岩石组成、岩-电关系等因素的影响,在准确发现和识别低渗透油气层(藏)中具有自身的技术优势。长期的勘探实践揭示,鄂尔多斯盆地延长组储集层具典型的低渗透、特低渗透特征,并使得单井产量较低,开发难度大,因而寻找相对高渗的优质油藏(田)成为石油勘探的重点和难点。同时,主力油层组的低渗、特低渗特征造成了:(1)岩性油藏是最主要的油藏类型,具有较大的隐蔽性;(2)储集层非均质性强,油层段渗流能力差异显著;(3)油水分异性变化较大;(4)储层含油性与典型的关系具不确定性,发育低阻油层和高阻水层(试油);(5)区带和油层组之间的储层润湿性存在差异,含油性相似的油层,其试油结果差异大;(6)由于低渗透油气藏普遍为低压异常,储层极易受到污染,钻井过程中地层中的天然气不会大量涌入井内,气体录井显示级别较低,受多种因素干扰不能真实反映储层含气量。由于上述原因,大大增加了油层准确识别及优质富油层段准确厘定的难度,因而在传统的地质录井、测井等识别油层技术的基础上,迫切地需要引用新的油层识别技术和综合识别技术,以提高油层识别的准确性,为探井试油层段的优选提供科学依据。论文选择典型的低渗透含油气盆地-鄂尔多斯盆地姬塬地区作为研究工区,研究应用岩石热解和热解气相色谱等地球化学方法,针对石油勘探中准确识别油气层这一技术难题,优选能够直接检测储集岩含油数量和组成性质的储岩热解、热解气相色谱等地化录井技术为手段,运用大量的储层物性、地层原油高压物性和原油全烃色谱、储岩残留烃气相色谱分析资料的基础上,确定了储集岩含油级别解释的各项参数,建立了适合研究区的储层含油级别解释方法、标准和图版,并通过与试油结果的对比分析,确认了其准确性和有效性。其良好的实用效果,特别是在低阻油层和高阻水层等的准确识别方面显示出的技术优势,昭示出该项技术良好的推广应用前景。论文在解决鄂尔多斯盆地低渗透储层的含油性与油层准确识别这一录井技术难题方面取得了以下主要的创新性进展:1.储集岩岩屑热解-气相色谱分析可获得热蒸发烃色谱谱图,可用于较准确判识储层含油与否、大致判别储层的含油性、以及油气显示的真伪。大量测试资料显示,姬塬地区不同含油性储岩的热蒸发烃色谱谱图十分相似,正构烷烃主要分布于C12~C34之间,异构烷烃、杂环烷烃的含量低。因此,该项技术应侧重于油气显示的定性识别方面。2.通过原油色谱分析与储岩快速色谱分析谱图的对比,确定热解分析样品的前处理过程中损失了nC12前组份,根据计算得出储岩热解总烃的恢复系数为1.4。3.根据油层含油饱和度与岩石热解烃量的理论关系式,通过试油结果与地化录井参数的对比分析,并考虑储层特点,分地区和油层组确定了油、水层的判识标准和理论图版。4.应用这套技术对姬塬地区延安组与延长组27层进行地化解释,与试油结果相比较,其中有21层地化录井解释结论与试油结果相符合,另有6层不符合,符合率为78%,较大地提高了录井综合解释水平,解决了低渗透储层油水层识别评价的难题。5.初步解决了低阻油层识别的难题。低阻油气藏油气层电阻率值接近或小于本地区相同地质条件下的水层电阻率,在高矿化度地区甚至低于围岩电阻率。低阻油气藏准确识别是测井技术的难点。通过岩石热解参数分析、气相色谱分析,确定储层原油性质,建立低阻油层、遭氧化油层的地化录井解释方法。对耿132井地化录井技术分析解释,发现了一层低阻油层,取得了长2层日产油10t/d的成果,对低阻油层的及时发现和准确识别具有重大的意义。总之,本论文以实际勘探生产中遇到的技术难题为研究攻关的对象,通过研究区石油地质特点的研究认识,方法试验,建立了具有代表性的几种复杂油水层评价模式,本论文以研究区石油地质特点的研究认识为基础,抓住储岩热解、热解气相色谱地化录井资料的解释这一关键环节,通过方法试验,确定了各项解释参数,从而建立了具有代表性的几种复杂油水层评价模式,综合常规录井、分析化验、测井、试油等资料等进行综合解释,在生产中应用见到了较好的效果,初步解决了目前制约勘探开发井筒评价发展的油水层评价难题;其解释评价结论为制定合理的射孔方案,判断试油压裂效果提供了可靠依据,减少了勘探风险,提高了勘探效益,实现从定性解释到定量评价的飞跃。本论文在突出了技术实用性的同时,也兼顾了学术理论性,同时,地质录井新技术的开发应用必须与地质实际紧密结合的学术思想也得到了较好的体现。
【Abstract】 In recent years, with the petroleum resource becoming increasingly tense, the domain of petroleum exploration and exploitation has been continuously expanded and extended. At the same time, the exploration targets have become more complex, the technical difficulty of the discovery of new oil (gas) reservoir (field) is also growing. Low permeability oil and gas resources found in the oil and gas resources as the proportion has increased year by year. Low permeability lithology reservoir (Field) has strong concealed, not typical four of the relationship, more complex oil and water relationships features, the use of conventional geological logging, logging and other technology tools in the discovery and evaluation of low permeability reservoir ( possession) often encountered some technical difficulties.Geochemical logging technology is a technology with the organic geochemistry detection technology development and improvement, combined with the oil and gas exploration and production technology needs, some people will be able to quickly detect reservoir the testing technology used in oil and gas drilling with logging work, and gradually develop and improve the technology of a quarry path in the 20th century to the late 1980s and early 1990s. The geochemical logging technology include many test technology which are used in oil quantitative and qualitative such as the reservoir rock pyrolysis, gas chromatography, fluorescence quantitative, UV, IR, and so on. And the characteristics of the geochemical logging technology is fast direct access to hydrocarbon reservoir rocks contained in the volume and composition of the exact nature of the information, thus, not rock, rock - relations, the impact of factors such as the accurate found and identification of low permeability reservoir (possession), with its own technological superiority.The long-term exploration practice revealed that the Ordos Basin Reservoir extension of a typical low permeability, ultra-low permeability characteristics, and makes low single well production, development difficulties and therefore find the relative quality reservoir hypertonic (fields) as oil exploration priorities and difficulties. At the same time, the major group of low permeability reservoir, causing low-permeability characteristics: (1) reservoir lithology is the most important reservoir type, the greater the hidden nature; (2) reservoir heterogeneity of the strong, Seepage of the reservoir capacity significantly, (3) changes in the oil water heterosexual large (4) of the oil reservoir and the relationship between a typical uncertainty of oil low resistivity and high water blocking layer (testing), (5) zone between the group and reservoir wettability of the reservoir there are differences of similar oil reservoir, the oil test results to vary (6) as the low permeability reservoir is generally very low pressure reservoir vulnerable to pollution, drilling in the process of formation of natural gas wells to be no significant influx, the gas log shows that lower-class, are many factors interference can not reflect the true reservoir gas content. Because of the above reasons, to greatly increase the quality reservoir accurate identification and rich reservoir of the difficulty of determining the accurate, and so the traditional geologic logging, logging and other identification on the basis of reservoir technology, there is an urgent need to use new identification technology and integrated reservoir identification technology so as to enhance the accuracy of reservoir identification, wildcat Optimization of the test reservoir to provide a scientific basis.In this Paper, we choose the typical low-permeability petroliferous basins - Ordos Basin Jiyuan region as our research area, the application of hot rock pyrolysis and gasification phase chromatography, and other geochemical methods for oil exploration in the oil and gas accurate identification of the technical problems can be optimized Direct detection of reservoir rocks oil volume and composition of the nature of reservoir rock pyrolysis, thermal gasification and gas chromatography, and other technologies as a means of logging, use of a large number of reservoir properties, the formation of high-pressure oil and crude oil all hydrocarbon chromatography, reservoir rocks Gas Chromatographic Analysis of hydrocarbon residue on the basis of information to determine the oil reservoir rocks level interpretation of the parameters established for the study area oil reservoir level interpretation methods, standards and maps, and through trial and the results of comparative analysis oil , confirmed its accuracy and effectiveness. Its good trial results, especially in the low resistivity and high water blocking formation of accurate identification, such as a show of superiority in technology, the technology has demonstrated a good promotion prospects.The paper in resolving the Ordos Basin in low permeability reservoirs of oil and oil accurately identify technical problems that logging has made the following main innovation of progress:1. Reservoir rock cuttings pyrolysis - Gas Chromatographic Analysis of available hydrocarbon Chromatogram thermal evaporation, can be used for accurate identification of reservoir oil or not, oil reservoir discrimination generally, as well as the authenticity of oil and gas shows. A lot of testing data shows that, in Jiyuan region, different areas of the oil reservoir rock hydrocarbon Chromatogram thermal evaporation is very similar to n-alkanes mainly distributed in the C12 to C34 between isoparaffin, heterocyclic paraffin content low. Therefore, the technology should be focused on the oil and gas shows in the qualitative identification.2. Through crude oil chromatographic analysis and reservoir rocks rapid chromatographic analysis of the spectra compared, we determine the thermal analysis of the samples before processing nC12loss of the group, calculated in accordance with reservoir rock pyrolysis total hydrocarbon recovery factor of 1.4.3. According to oil saturation and reservoir rock pyrolysis of hydrocarbons relations theory, the adoption of test results and oil and logging parameters of the comparison and analysis, and taking into account reservoir characteristics, sub-regional and determined the fuel reservoir, the water layer identification standard and theoretical chart.4. We apply this technology to explain the Jiyuan region Yan’an group and Yanchang group 27th-storey, compared to the results of the test oil one in 21 of the conclusions and interpretation of logging test results in line with oil, and not in line with a six-storey, the congruous rate is 78%, significantly increased levels of logging comprehensive interpretation, and solve the identify problem s of low permeability reservoir evaluation of oil-water layer.5. Solve the problems of low resistivity reservoir identification. Oil and gas reservoirs low resistivity layer resistivity of less than or close to the same geological conditions in the region under the water layer resistivity, high salinity in the region is even lower than rock resistivity. Low resistivity reservoir accurate identification is the difficulty of logging technology. Through rock pyrolysis parameter analysis, gas chromatography analysis, oil reservoir in nature, the establishment of low resistivity reservoir, the reservoir was oxidized to explain methods of logging. Geng132 wells on the technical analysis of log interpretation, reservoir found a layer of low resistivity, made Chang2 layer the oil-producing 10 t/d the outcome of the formation of low resistivity timely detection and accurate identification is of great significance.In a word, the research object of this paper is the technical problems we encountered in actual exploration and production, petroleum geology study area characteristics of understanding, test methods, the establishment of a representative of several complex evaluation of oil-water model to study papers District petroleum geological characteristics of knowledge-based, seize the reservoir rock pyrolysis, gasification phase chromatography and thermal logging data interpretation of this critical link, through means test to determine the parameters of the explanations, which has established a representative Several of the complex evaluation of oil-water layer model, the composite conventional logging, laboratory analysis, logging, test data and other oil comprehensive explanation, see the application in the production of good results and solve the current exploration and development constraints wellbore evaluation of development Evaluation of the water problem; its interpretation of evaluation findings for the development of the perforation programme reasonable judgement oil fracturing test results provide a reliable basis to reduce exploration risk and enhance the efficiency of exploration, from a qualitative interpretation of the quantitative evaluation leap. The paper has important signification in both technical practices and the academic theory, at the same time, the development and application of the new geologic logging technology of new technology must be closely integrated with the geological and academic thinking has also been embodied better.
【Key words】 Low permeability reservoir; Geochemistry; Rock thermolysis; Gas chromatography; Oil-water layer identification;