松辽盆地营城组玄武岩流动单元测井响应特征

流动单元是玄武岩地层的最基本组成单元,其内部分带性控制储层的储集性能和有效储层的分布位置.运用钻井岩心资料建立了玄武岩流动单元分带地质模式,单个流动单元由上而下依次为上部气孔带、中部致密带和下部气孔带.依据自然伽马(GR)、声波时差(DT)、补偿密度(RHOB)、深侧向电阻率(LLD)和中子孔隙度(NPHI)分析流动单...     

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.     

基于DBN模型的火山岩岩性识别方法——以车排子地区为例

准噶尔盆地西北缘红车断裂带石炭系火山岩储层历经火山多期喷发形成,岩石矿物组成与岩石结构复杂、岩石类型繁多,导致常规方法识别岩性存在困难.为了能提高火山岩岩性识别精度,提出一种基于深度置信网络(DBN)识别岩性的方法.本文通过对薄片鉴定资料、岩心观察资料及测井数据统计分析,根据火山岩类型总结的测井响应特征绘制交会图,发现...     

盐水泥浆条件下定向井双侧向测井环境校正方法研究

在定向井中,双侧向测井数据由于受井眼、围岩、井斜、径向侵入等环境因素的影响,难以准确地估算储层的电阻率和更准确地识别储层流体.本文拟提出图版法和反演法相结合的思路来研究地层视电阻率的校正问题.首先,针对研究区的测井环境和钻井液电阻率,计算了不同尺寸井眼的双侧向测井响应,绘制了井眼校正图版;然后,针对斜度井地层模型,采用三维有限元方法计算了不同井斜、不同厚度地层的测井响应,构建了井斜-围岩/层厚图版,利用该图版实现了井眼校正和井斜-围岩/层厚的电阻率快速校正.最后,针对钻井液侵入的影响,采用反演方法计算了侵入半径和地层真电阻率,最终实现了双侧向测井的环境校正.利用上述理论与方法对海洋中定向井的双侧向测井资料进行了环境校正,提高了储层流体定性识别和定量评价的精度.     

火山岩储层测井评价技术现状及发展趋势

近些年来,火山岩油气藏已成为国内外研究和开发热点之一,我国已先后在多个盆地的火山岩油气藏勘探中取得重大突破.测井资料在各种类型油气藏评价中一直发挥着不可替代的重要作用,但由于火山岩储层岩性及储集空间等方面的复杂性,其测井评价难度更大、更具挑战性.本文主要针对近些年来测井技术在火山岩油气藏岩性评价、有效储层识别与物性参数评价、储层流体性质评价等方面的应用进行系统的归纳和总结,并结合已有研究成果及生产实践对火山岩储层测井评价的基本发展趋势进行分析展望,以期为火山岩油气藏的进一步勘探开发提供技术支持.     

基于孔隙结构的酸性火山岩储层流体识别方法研究

酸性火山岩山于成岩矿物类型多样,孔隙结构复杂,电阻率普遍较高,应用常规的中子-密度测井曲线交会和电阻率的高低已经不能判断储层流体性质.在天然气的测井响应特征分析基础上,应用三孔隙度组合、横纵波时差比值、核磁共振及综合参数识别流体性质.应用结果表明这些方法只能识别含气储层,对于气水同层的识别效果并不好.电阻率对储层流体性...     

核磁共振测井技术在桩海地区及其它油田中的应用

阐明核磁共振测井（NMR）在储层评价中的作用。利用NMR测井资料对桩海地区长堤油田的储层特性及产能、复杂岩性储层的孔隙度作出评价，并在电阻率测井资料显示不好的复杂储层条件下进行油气水层识别，以及指导完井和钻井方案的实施等。不阐明了核磁共振测井技术具有常规测井技术所不具备的特点，特别是定量的评价孔隙流体流动特性、准确划分产层、直接识别油气水等优点，从而有利于解复杂的地质问题。     

准噶尔盆地陆东-五彩湾地区石炭系火山岩电性与地震响应特征

勘探实践证实,准噶尔盆地石炭系已成为一套现实勘探层系;陆东-五彩湾地区石炭系火山岩体规模大、分布广,是重要的天然气储集体;火山岩储层有效性主要受不整合、岩性、岩相控制,识别火山结构、火山岩岩性、岩相成为判别储层有效性的关键.由于主要目的层巴塔玛依内山组特殊的三段式火山岩组合层序结构,为通过测井、地震物探手段识别火山岩岩...     

测井储层分类评价方法研究进展综述

测井储层分类方法多样,每种方法的原理、计算步骤及所需资料各不相同,且各方法的适用性及应用效果均存在很大差异,本文通过文献调研,将测井储层分类方法归纳为四大类:(1)基于交会图版法的半定量储层分类方法,此方法操作简单、应用范围广但适用性不强;(2)基于流动单元概念的测井储层分类方法,此方法基于岩心物性数据可以迅速达到储层分类的目的 ,具有明确的地质意义,但结果依赖于取心数据;(3)基于多元统计法及机器学习算法的测井储层分类方法,此类方法可以有效地避免人为因素的干扰,速度快、方法多样,可以实现储层的定量分类评价,是未来发展的趋势,但分类结果意义不明确;(4)基于测井新技术新方法的储层分类方法,该方法携带了大量的地质信息,与其他分类方法结合可以更有效、更准确地评价储层.最后比较了四种分类方法的优缺点并给出了相应的选择建议,该研究对测井储层分类方法的优选具有一定的参考意义.     

鄂尔多斯盆地天然气有效储层识别与评价方法

针对鄂尔多斯盆地天然气勘探开发存在的问题,通过对测井资料及天然气测试资料的分析,建立适合识别天然气有效储层的测井响应特征归一化方法,以及根据测井资料重构天然气有效储层特征曲线的方法,探索了根据测井资料评价天然气产能的方法.本文还分析了目前常用的预测天然气产能方法存在的问题及实际应用中欠缺的条件,形成了以中子、声波、密度测井资料为基本特征参数,用自然伽马、自然电位或电阻率比值参数等作为约束条件的天然气有效储层识别技术及天然气产能评价方法,并对实际测井资料进行了处理.没有试图通过井径校正的方法将受井径扩大影响的曲线恢复到原始地层的响应状态,而是通过极值变化消除井径扩大对声波、密度测井资料在天然气有效储层识别及天然气产能评价方面应用的影响.     

On the synchronism in the events within the core and on the surface of the earth: the changes in the organic world and in the polarity of the geomagnetic field in the phanerozoic

The data on geomagnetic reversals are compared with the changes in the organic world and with the lower-mantle plumes. The times of the formation of plumes and the times of their appearance on the Earth’s surface relate to the intervals characterized by the different frequencies of geomagnetic reversals, i.e., there is no interrelation between the formation of plumes and the frequency of the changes in the geomagnetic field polarity. At the same time, a certain synchronism is observed between the frequency of the geomagnetic reversals and the boundaries of the biostratigraphic ages, i.e., the changes in the organic world in the long-period range. A hypothesis is proposed, which explains the change in the sign of the geomagnetic field by the combined effect of the irregular rotation of the internal core relative to the mantle and the changes in the slope angle of the axis of the Earth’s rotation, which, in turn, results in synchronous events on the Earth’s surface: the rates of changes in the organic world.     

On the gravimetric undulations of the geoid and the deflections of the vertical

Summary The author mentions the aims of the World-wide gravity project he established in the Ohio State University in Columbus, in 1950. He outlines the practical procedure of the gravimetric computations of the undulationsN and the vertical deflection components and and emphasizes that only by the global international cooperation and additional gravity observations at sea carried out during the last decade it has been possible to gather to Columbus the needed gravity material. Since there exist still large gravimetrically unsurveyed areas it is of vital significance to study what gravity anomalies are best to be used for these regions. The given figures concerning the accuracy of theN, and , estimated theoretically and obtained in practice, indicate that in the gravimetrically well surveyed parts of the world like in Europe and the United States we can get gravimetrically on basis of existing gravity material theN-values with accuracy of about 5–10 meters, and and with the accuracy of about 1. The geoid undulationsN are already computed in Columbus for more than 6000 points of the northern hemisphere. The sample maps show the interesting geoid of Europe and vicinity between the latitudes 60° and 30° and longitude 5° W and 30° E, drafted on basis of more than 1000N-values computed at the corners of 1°×1° squares. It is interesting to realize that the geoid undulations in all this area are positive, the extreme values being between 40 and 50 meters. The geophysical significance of the geoid maps of this kind is pointed out.     

On the maintenance of the axisymmetric part of the flow in the atmosphere

Summary The maintenance of the axisymmetric component of the flow in the atmosphere is investigated by means of a steady-state, quasi-geostrophic formulation of the meteorological equations. It is shown that the meridional variations in the time-averaged axisymmetric variables can be expressed as the sum of three contributions, one being due to the eddy heat transport, another to the eddy momentum transport, and a third to the convective-radiative equilibrium temperature which enters the problem through the specification of a Newtonian form of diabatic heating. The contributions by the large scale eddies are evaluated through the use of observed values for the eddy heat and momentum transports.The contributions from each of the three forcing mechanisms to the temperature and zonal wind fields are invstigated individually and found to be of about equal importance. The sum of the three contributions are also presented for the temperature, the zonal wind, the stream function associated with the mean meridional circulation and the corresponding vertical motion. Although the results fail to reproduce the main observed features of the lower stratosphere, they are found to be in good agreement with observations in the middle latitude troposphere. At any pressure level, for example, the computed mean zonal wind has a jet-like profile and the axis of the jet is found to slope to the south with height, as observed in the atmosphere.Based in part on a thesis submitted by the first author as partial fulfillment of the requirements for the Ph.D. degree at the University of Michigan. — Publication No. 194 from the Department of Meteorology and Oceanography, The University of Michigan.     

太平洋中部地磁台11年周期变化的研究

综合APIA、HONOLULU、PAMATAI 3个地磁台三分量的11年周期变化的形态后,可定性地提出该变化源于内场。如内源为核幔边界的电涡流,则其中心点应位于3台之间。     

Comparison Between the Nutations of the Planet Mars and the Nutations of the Earth

The nutations of the planets Mars andEarth are investigated and compared. Alarge number of interior structureparameters are involved in the nutationcomputations. The comparison between the observations and the computationsprovides several constraints on these parmeters andtherefore allows a better understanding of the physics of the interior of theplanet. For the Earth, the high precision of the observations of the nutationshas led to a very good determination of interior properties of the planet. ForMars, observations of nutations are not yet available, and we review how theamplitude of the Martian nutations depends on the hypotheses consideredfor its interior. Although Mars is very similar to the Earth, its interior is not well known;for example, we don't knowif its core is liquid or solid. Only if the core is liquid,the Free Core Nutation (FCN) normal mode exists and can alter the nutationswhich are close to the resonance. From the observed geoids, it is known thatboth planets are not in hydrostatic equilibrium. The departure is larger forMars than for the Earth, and consequently, the implication of considering a convective mantle instead of a mantle in hydrostatic equilibrium described byClairaut's equation for the initial equilibrium state of the planet is largeron the Martian nutations than on the Earth nutations. The consequences of theuncertainty in the core dimensions are also examined and shown to be of a veryhigh influence for Mars if the core is liquid, due to the potential changes inthe FCN resonance. The influence of the presence of an inner core, which isknown to exist for the Earth, could be more important for Mars than for theEarth if the inner core is large. Due to the presence of Tharsis on Mars, thetriaxiality of this planet has, additionally, larger effects than on Earth.     

Magnetic stratigraphy of the Ordovician in the lower reach of the Kotuy River: the age of the Bysy-Yuryakh stratum and the rate of geomagnetic reversals on the eve of the superchron

Until recently, the existing data prevented the geophysicists from accurately dating the Bysy-Yuryakh stratum, which outcrops in the middle reach of the Kotuy River, constraining the time of its formation to a wide interval from the end of the Late Cambrian to the beginning of the Silurian. The obtained paleomagnetic data unambiguously correlate the Bysy-Yuryakh stratum to the Nyaian regional stage and constrain its formation, at least a considerable part of it, by the Tremadocian. This result perfectly agrees with the data on the Bysy-Yuryakh conodonts studied in this work and yields a spectacular example of the successful application of paleomagnetic studies in solving important tasks of stratigraphy and, correspondingly, petroleum geology. Within the Bysy-Yuryakh stratum, we revealed a large normal-polarity interval corresponding to the long (>1 Ma) period when the geomagnetic reversals were absent. This result, in combination with the data for the Tremadocian and Middle–Upper Cambrian sequences of the other regions, indicates that (1) the rate of occurrence of the geomagnetic reversals on the eve of the Ordovician Moyero superchron of reversed polarity was at most one reversal per Ma; (2) the superchron does not switch on instantaneously but is preceded by a certain gradual change in the operation conditions of the dynamo mechanism which, inter alia, manifests itself by the reduction of the frequency of geomagnetic reversals with the approach of the superchron. This finding supports the views according to which a process preparing the establishment of the superchrons takes place at the core–mantle boundary.     

On the variation in the geomagnetic dipole over the geological history of the Earth

The global database on the paleointensity, containing determinations of the virtual dipole moment (VDM) for a stable (normal) regime of the geomagnetic field in a time interval of up to 3.5 Ga, is supplemented by new VDM determinations and analyzed. The field generation process started no later than 3–3.5 Ga (earlier data are absent) at the stage of the Earth’s core formation. Since that time, the dipole value has differed from its present value by no more than an order of magnitude, and the deviations that have already been detected tend toward smaller values. The distribution of VDM values in the time interval 0–400 Ma is bimodal, which apparently reflects the presence of two different generation levels of the geomagnetic field distinguished by a relatively large value (close to the present field value) and a relatively small value (approximately half as large as the present value). The total duration of decreased VDM values appreciably exceeds that of increased VDM values (179.1 and 28.6 Myr, respectively). On the whole, data on the paleointensity do not contradict the hypothesis about the dipole nature of the field over the last 400 Myr; however, the number of determinations at high paleolatitudes is too small to draw decisive conclusions on the validity (or invalidity) of the dipole field approximation based solely on paleointensity data.     

Structure of the poleward wall of the trough and the inclination of the geomagnetic field above the EISCAT radar

A special high-resolution routine of the EISCAT radar has been used to investigate the structure and development of the poleward wall of a deep trough in electron density. The feature was tracked by the radar during a 7-hour period under very quiet geomagnetic conditions. The field-aligned nature of the structure enabled an estimate to be made of the inclination of the geomagnetic field above EISCAT that was in good agreement with the current model. Observations of narrow field-aligned enhancements in electron temperature demonstrated that the wall of this trough is a dynamic feature, reforming regularly as the electron density responds on a time scale of tens of minutes to energy input from soft-particle precipitation.