测井资料在储层预测研究中的应用

测井解释技术面临三方面制约因素:(1)长期以来仪器的发展速度快于解释评价的发展速度,使大量有用信息被长期掩盖;(2)现今测井评价方法强于微观解释而弱于宏观分析,明显限制了测井技术的发展和受重视程度;(3)油气勘探开发目标的日益复杂化,对测井技术提出了更高要求.开展测井储层预测技术的探索,在某种程度上可弥补上述不足.本文提出测井储层预测技术研究的二个依据,(1)将测井资料作为宏观地质作用与微观岩石信息统一关系论证的一个关键点,寻找测井信息能准确描述二者具有统一成因关系的证据;(2)以构造-沉积演化作为研究切入点,预测特殊储层在时、空的分布关系.基于上述认识,以印尼B油区裂缝型砂岩的预测以及大港油田Q50断块低阻油层的预测研究为例,分别介绍了测井储层预测技术的2个应用实例.     

水平井测井解释技术综述

水平井的大规模钻井和应用是二十世纪后期石油工业的一个亮点.水平井技术在新油田开发和老油田调整挖潜上成效显著,它可降低勘探开发成本、大幅度提高油气单井产能和采收率等.回顾了水平井及水平井测井解释发展历史,比较了垂直井和水平井测井及解释评价上的异同,分析了水平井测井环境以及测井解释所面临的问题,简述了一些水平井测井数据处理方法及综合解释中应注意的问题,最后根据我国目前的水平井测井解释现状分析了存在的问题,提出了今后发展的思路：以跟踪国外和创新发展国内水平井解释技术为目标,开展复杂条件下各种测井方法的正反演研究,研究各种环境影响因素的校正方法,注意多学科的交叉综合,结合垂直井测井解释经验和水平井测井的特点提高水平井测井解释水平.     

SG地区叠前地震弹性参数交会定量解释技术预测有效储层的方法

鄂尔多斯盆地SG气田是我国典型的低孔,低渗,致密砂岩气藏的代表.该区地震勘探开发面临着两大难题:一是含气砂岩和围岩的声波阻抗存在较大范围叠置,利用声波阻抗预测储层存在明显的多解性;二是SG气田局部地区气、水关系复杂,地质上不存在统一的气、水层分界面,产水井严重影响产能建设,流体类型的识别是面临的又一难题.为了降低声波阻抗预测砂岩储层的多解性,提高有效储层预测精度,定量识别储层中流体的类型,本文提出了叠前地震弹性参数交会定量解释技术,从横波测井资料不同岩性、流体的岩石物理参数分析入手,优选了能够区分岩性和流体的最佳敏感弹性参数,制作了敏感弹性参数交会模板,通过地震叠前反演获得反映储层物性和含气性的地震弹性参数体,最后进行地震弹性参数交会定量解释预测有效储层和识别流体.勘探实例证实了该技术方法在SG地区对有效储层的预测是有效的,能够为井位优选提供可信的依据.地震弹性参数交会技术将纵向分辨率较高的测井岩石物理分析和横向分辨率较高的地震叠前反演结合在一起,使用了多个弹性参数交会,减少了以往单一弹性参数预测储层的多解性,最终获得比较可靠、更量化的反映储层物性和含气性的地震弹性参数交会体,为有效储层预测和流体识别探索出了新的途径,这一技术的应用和推广可以降低地震解释的风险,提高储层预测精度.     

松南气田火山岩储层测井解释研究

火山岩储层总体属于低孔渗储层评价的范畴,由于测井含气响应远弱于岩石骨架响应,流体识别面临气、水层区别难的问题;由于岩性和孔隙结构复杂引起阿尔奇参数多变,测井解释面临饱和度定量计算精度不高等问题.针对上述问题,提出“定性解释与定量解释相互独立、相互验证”的火山岩测井解释原则.在气层识别方面,从重构孔隙度气层识别组合曲线、研究电阻率相对值、应用核磁测井技术以及分析储层含气丰度与测井响应差异等四个研究方向探索了不同储层的测井识别依据,根据上述研究成果,确定了5类储层的测井判别依据,实现了火山岩定性解释;在火山岩定量解释方面,由于电阻率曲线本身就是岩性和孔隙结构的综合反映,引入基于电阻率测井响应的可变m值阿尔奇计算公式,应用生产测试成果验证,证实该方法定量计算储层含气饱和度精度高.根据上述研究成果,系统建立了松南火山岩测井解释模型.应用新的火山岩储层测井解释方法,多口新井的测井预测结果被生产测试所验证,应用效果良好.     

特低渗储层测井评价技术综述与展望

特低渗储层的测井响应特征与常规储层不同。测井响应值难以有效表征孔隙中的油气,不同品质储层间的差异性不明显.利用单一的测井解释方法容易引起多解性和模糊性,测井参数解释难度大,油气识别非常困难.为了更好地实现特低渗储层的测井精细评价,提升测井解释的符合率,本文在大量文献调研的基础上,依托前人的研究成果,详细归纳总结了裸眼井和套管井的测井系列之后,对其特低渗储层的常规测井评价方法及其优缺点进行了系统梳理和深入剖析,并探讨了核磁共振测井、高分辨率阵列感应测井、电阻率成像测井等新技术和非线性数学方法在特低渗储层中应用状况.最后基于特低渗储层地球物理测井技术的发展现状,指出了当前测井评价技术面临的困难和问题,并展望了特低渗储层地球物理测井技术的发展趋势.     

油气地球物理勘探技术进展

文章回顾了中国油气测井、物探的发展历程,分析了中国油气地球物理勘探方法研究、装备、处理解释技术的现状及在世界油气勘探中的地位,分别从测井技术的方法、井下仪器、地面系统及资料处理解释评价方面和地震勘探的方法、震源、检波器、地面系统及资料处理解释方面介绍了中国油气地球物理勘探技术的发展及方向.     

胜利油田核磁共振测井技术应用回顾与展望

核磁共振测井以全新的原理,提供了一套全新的信息和响应关系,能够对地层油气评价的基本问题,进行全新的解答.胜利油田自1996年开始使用核磁共振测井以来,至今已经积累10余年的测井应用经验.总结核磁共振测井技术在胜利油田的发展应用,其发展经历了三个阶段:初步探索阶段,研究应用阶段和完善深化阶段.在初步探索阶段主要是以储层识别以及孔隙度、渗透率、饱和度等岩石物理参数为主;在研究应用阶段主要是利用T2分布形态进行流体识别和孔隙结构研究;完善深化阶段则是提高解释评价精度,针对勘探开发中的评价难题深化地质应用.目前,核磁共振测井技术在胜利油田的应用已经逐步完善成熟,已成为提高油田勘探开发效益必不可少的手段.在储层评价、参数计算、流体识别中发挥了重要作用,尤其是在单纯依靠常规测井难以进行流体识别的低电阻率/电阻率低差异、低孔隙度、低渗透率、砂砾岩体、复杂岩性等油气藏评价中发挥了独特的作用.     

精细构造解释及储层预测技术在轮南地区的应用

轮南油田三叠系TⅠ—TⅢ油组为辫状河三角洲沉积,具有砂体横向变化快,储层厚度薄,油藏埋藏深的特点,且低级序断层较为发育,对研究区断层及储层发育特征认识尚不清楚,给油田开发带来了较大的影响.为了达到增储上产及寻找新的滚动开发目标的目的,综合多种技术手段对油田精细构造和储层预测进行了研究.利用时间切片技术、相干体刻画技术、蚂蚁追踪技术三种技术相结合的方法对不同级序的断层进行了精细解释,结合精细变速成图技术,落实了轮南地区精细构造特征.采用地震属性优选分析,流体检测技术与测井曲线重构反演技术结合的方法进行储层预测.通过属性优选发现,振幅属性能较好反映储层的变化,在TⅡ油组衰减梯度属性能较好反映流体的分布特征.优选出SP与AC曲线进行曲线重构,最终得出高分辨率的波阻抗反演剖面,纵向分辨率与横向分辨率均较高.通过对以上多种技术的综合研究,为轮南地区油藏精细开发及滚动勘探提供了依据.     

珠江口盆地西南部深水区S1构造油气储层预测与烃类检测

储层预测与烃类检测是深海油气勘探决策的关键环节,关系到深海油气勘探部署.然而,受海上钻井稀疏(甚至没有钻井)、缺乏测井资料、3D地震资料等不利因素,深海油气储层预测与烃类检测面临极大的技术挑战.本文以南海珠江口盆地西南部深水区S1构造研究为例,在研究区没有钻井、仅7条长63 km的二维地震测线的资料条件下,以邻区相似构...     

页岩气地球物理测井评价综述

页岩气是指生成、储集和封盖均发生于页岩体系中,或游离于基质孔隙和天然裂缝中,或吸附于有机质和粘土矿物表面,或溶解于沥青和水中,在一定地质条件下聚集成藏并具有商业价值的生物成因和/或热解成因的天然气.在页岩气勘探开发中,地球物理测井是识别、评价页岩气储层并为后期完井提供指导参数的重要手段.页岩气属于极低孔极低渗的范畴,且具有很强的非均质性和各向异性,常规油气藏测井解释评价方法已不再适用,必须建立新的页岩气测井解释评价体系才能够对页岩气藏做出准确评价.评价页岩气藏的潜力涉及对多种因素正反面影响的权衡,包括页岩矿物组分和结构、粘土含量及类型、干酪根类型及成熟度、流体饱和度、吸附气和游离气存储机制、埋藏深度、温度和孔隙压力等.其中,孔隙度、总有机碳含量和含气量等对于确定页岩储层是否具有进一步开发价值非常重要.本文针对国外尤其是美国近期页岩气勘探开发的现状进行了广泛的文献调研,综述当前国外页岩气地球物理测井技术的发展现状,针对勘探开发的不同阶段介绍常用的含气页岩的测井系列,然后总结页岩气测井响应特征,并详细论述了页岩气储层评价方法及储层评价的重要参数,包括有机碳含量、岩石矿物组分及含量、孔隙度、含气量及岩石力学参数,最后提出我国页岩气地球物理测井研究存在的问题和发展趋势.     

Changes in sediment transport in the Kuye River in the Loess Plateau in China

In this paper, the changes in sediment transport over 51 years from 1955 to 2006 in the Kuye River in the Loess Plateau in China are assessed. Key factors affecting sediment yield and sediment transport, such as precipitation depth, discharge, and human activities are studied. To investigate the changes in sediment yield in this watershed, a trend analysis on sediment concentration, precipitation depth, and discharge is conducted. Precipitation depths at 2 Climate Stations （CSs）, as well as discharge and sediment transport at 3 Gauging Stations （GSs） are used to assess the features of sediment transport in the Kuye River. The rtmoff modulus （defined as the annual average discharge per unit area, L/（s·km^2）） and the sediment transport modulus （defined as the annual suspended sediment transport per unit area, t/（yr km^2）） are introduced in this study to assess the changes in runoff and sediment yield for this watershed. The results show that the highest average monthly discharge during the study period in the Kuye River is 66.23 m^3/s in August with an average monthly sediment concentration of 88.9 kg/m^3. However, the highest average monthly sediment concentration during the study period in the Kuye River is 125.34 kg/m^3 and occurs in July, which has an average discharge of 42.6 m^3/s that is much less than the average monthly discharge in August. It is found that both the runoff modulus and sediment transport modulus at Wenjiachuan GS on the Kuye River has a clear downward trend. During the summer season from July to August, the sediment transport modulus at Wenjiachuan GS is much higher than those at Toudaoguai and Longmen GSs on the Yellow River. The easily erodible loess in the Kuye River watershed and the sparse vegetation are responsible for the extremely high sediment yield from the Kuye River watershed. The analyses of the grain size distribution of suspended load in the Kuye River are presented. The average monthly median grain size of suspended load in the Kuye River is largest in February and then decreases until June. In July, the average monthly median grain size of suspended load approaches another peak and decreases until September. Then, the median grain size of suspended load starts to increase until February of the following year. However, the average monthly median grain size of suspended load in the Yellow River at Toudaoguai and Longmen GSs is the smallest between early summer and late fall The median grain size in the Yellow River starts to increase in November and approaches the largest size in January.     

TritiogenicHe in groundwater in Takaoka

³He/⁴He ratios up to 3.5 times the ratio of atmospheric He were found in groundwater samples. The³He enrichment can be attributed to radiogenic³He produced by in-situ beta-decay of³H. This shows that tritiogenic³He is accumulating in confined waters. From tritiogenic³He and³H concentrations, ages of groundwaters can be calculated. Detection of tritiogenic³He gives a tool to trace a tritium contamination which occurred in the past and cannot be assessed only by the³H counting method.     

Variations in trace gas concentrations in different environments in India

Observations of trace gases (SO₂, NH₃, NO₂ and O₃) were made during the period 1981 to 1984 at 6 different locations representative of urban industrial, urban, nonurban, thermal power plant and marine environment. Diurnal variations of the trace gases were studied in an urban environment. Except in the urban industrial environment, the concentration of NH₃ was found in the range of background values. Also, the average concentrations of NO₂ and O₃ at the different environments were in the order of background values. However, the concentrations of SO₂ were substantially higher by about 7 times, in urban industrial and thermal power plant environments. The diurnal variations of SO₂, NH₃ and NO₂ showed anitphase relationship with surface temperature at the urban environment station which is relatively free of industrial pollution. Discussion is centred on trace gas variations in different environments in India together with the values reported for various countries in the world.     

Projected changes in flood indices in selected catchments in Poland in the 21st century

The aim of this study is to estimate likely changes in flood indices under a future climate and to assess the uncertainty in these estimates for selected catchments in Poland. Precipitation and temperature time series from climate simulations from the EURO-CORDEX initiative for the periods 1971–2000, 2021–2050 and 2071–2100 following the RCP4.5 and RCP8.5 emission scenarios have been used to produce hydrological simulations based on the HBV hydrological model. As the climate model outputs for Poland are highly biased, post processing in the form of bias correction was first performed so that the climate time series could be applied in hydrological simulations at a catchment-scale. The results indicate that bias correction significantly improves flow simulations and estimated flood indices based on comparisons with simulations from observed climate data for the control period. The estimated changes in the mean annual flood and in flood quantiles under a future climate indicate a large spread in the estimates both within and between the catchments. An ANOVA analysis was used to assess the relative contributions of the 2 emission scenarios, the 7 climate models and the 4 bias correction methods to the total spread in the projected changes in extreme river flow indices for each catchment. The analysis indicates that the differences between climate models generally make the largest contribution to the spread in the ensemble of the three factors considered. The results for bias corrected data show small differences between the four bias correction methods considered, and, in contrast with the results for uncorrected simulations, project increases in flood indices for most catchments under a future climate.     

Copper in natural waters in Transbaikalia

Cu concentrations in surface (river and lake) and subsurface waters are determined. The geographic pattern of Cu distribution in natural water is identified. This pattern is controlled by the difference between its concentrations in drained rocks and soils and the geochemical redox conditions of its migration. Territories with low, medium, and elevated Cu concentrations in natural waters are identified. The concentrations of Cu in natural waters of the region are found to be generally lower than the Clarke values.     

Changes in thermal extremes in Poland

Changes in thermal extremes of the climate of Poland in 1951–2010 are examined. Warm extremes have become more frequent, while cold extremes have become less frequent. In the warming climate of Poland, the increase in the number of extremely warm days in a year and the decrease in the number of extremely cold days in a year have been observed. Also the increase of the maximum number of consecutive hot days in a year and the decrease of the maximum number of consecutive very cold and extremely cold days in a year have been observed. However, the trends are not of ubiquitous statistic significance, as the natural variability is strong.     

Hydrological changes in the Ganges system in Bangladesh in the post-Farakka period

Abstract

The basin area of the Ganges River in Bangladesh is extremely dependent on a regular water supply from upstream to meet requirements for agriculture, fisheries, navigation, salinity control, and domestic and industrial sectors. In 1975, India commissioned a barrage on the Ganges River at Farakka to divert a significant portion of the dry season flow in order to make the Calcutta Port navigable. Statistical analyses of discharge and water level data have been carried out to determine if significant changes have occurred in the hydrology of the Ganges system in Bangladesh in the post-Farakka period. Siltation of the Gorai River (an offtake of the Ganges River) has also been examined using the stage-discharge relationship and regression analysis. The analyses show that the diversion has caused considerable hydrological changes in the Ganges system in Bangladesh. The water supply in the dry season has been reduced substantially, while siltation of the Gorai River has increased significantly.     

Advances in ground motion studies in China

This paper briefly summarizes the works in the processing of strong ground motion data, the factors affecting strong ground motion, the modeling of strong ground motion and the calculating of broad-band response spectrum which have been done recent years by engineering seismologists and seismologists of China. In addition, we think back to the international cooperation in strong ground motion of the recent years and make some expectations for the future.