水灰炭地层各孔隙度中子随能量时间分布MonteCarlo模拟

作者在MCNP的基础上，开发了中子测井，中子通量随能量、时间分布蒙特卡罗（MC）模拟软件包，对裸眼井、井眼里无下井仪器、淡水饱和灰岩地层、井眼注淡水，用该软件计算了井轴和井壁一确定点,各孔隙度中子量通量，时间分布。即孔隙度对中子通量随量、时间分布和热中子、超热中子时间谱的影响。     

水层多角度裂缝介质中子测井响应数值模拟

地球物理勘探作业中,裂缝地层是一种重要的潜在储层介质,因为其结构的复杂性和成因的特征性,裂缝介质的探测难度一直较大。为了对裂缝介质进行识别及研究,通过地球物理中子测井方法对其进行勘探研究是十分必要的。笔者应用分散多角度裂缝理论,模拟孔—裂缝介质中的含水地层,通过变化裂缝参数研究对应的中子测井数据。研究结果发现,中—低角度的裂缝介质中,热中子密度极大值比近似水平角度裂缝介质中的密度极大值大,并且其对裂缝环境参数的敏感度也明显大于其他角度裂缝介质中的热中子密度敏感度;在高角度裂缝介质中,热中子密度图分布平滑,说明高角度裂缝介质对热中子吸收作用较小;在热中子密度分布平面图中,因水中含氢量较大,热中子扩散范围小。通过分析水层中的热中子密度分布情况、密度分布极大值以及时间谱最大值,发现水层中的中子对中等角度和低角度的裂缝介质更加灵敏,且容易被慢化和吸收。这些研究结果可以为野外裂缝性介质的地球物理勘测工作提供理论指导建议。     

空气钻井条件下中子孔隙度测井响应的蒙特卡罗模拟

空气钻井作为一种欠平衡钻井技术,会对中子孔隙度测井产生不同的影响。利用蒙特卡罗方法建立裸眼井的中子孔隙度计算模型,模拟空气钻井时不同孔隙度、岩性、泥质含量、井眼尺寸、井筒空气压力条件下的中子输运过程,研究热中子计数比值与孔隙度的关系。认为空气钻井时远近探测器的热中子计数都随孔隙度的增加而增加,然后再缓慢减少;石灰岩地层的热中子计数率比值高于砂岩,泥质含量越高的地层热中子计数率比值越大;井眼尺寸对热中子计数率比值影响很大,孔隙度越大的地层井眼尺寸影响越大,且井眼尺寸越大,比值变化越小,越不利于中子孔隙度的确定;井筒空气的压力大小对热中子计数率比值影响很小。因此空气钻井时必须重新刻度中子孔隙度,并对岩性、泥质含量、井眼尺寸等因素进行校正。     

铁基样品中锰的中子活化法测定

采用热中子与超热中子照射相结合的中子活化法测定了铁高含量样品中锰的含量。实验测定和理论计算了铁对锰的干扰系数，两者符合较好。对几个标准物质的分析结果与推荐值相符。该方法适用于ｍＦｅ／ｍＭｎ小于２×１０５的样品中锰含量的测定     

用超热中子活化分析法测定矿石中金时对减低因子的评价

本文阐述了用超热中子活化分析测定矿石样品中金时，由于超热中子自屏蔽产生的金的减低情况，制备了３种不同金粒度范围的合成金矿样，并分别用热中子活化分析方法和超热中子活化方法分析。３种金粒度的范围即≤５３μｍ、５３－１５０μｍ和１５０－２５０μｍ合成的矿样，超热中子活化分析结果与热中子活化分析法比较，金分别降低了１１％、３１％和３３％，同时测量金的标准参考矿物ＭＡ－１的减低因子为５％，加拿大ＣＡＮＭＥＴ     

微型核反应堆中子活化分析测定地质样品中的卤素元素

研究了微堆中子活化分析测定地质样品中卤素元素的测量条件和测量中的影响因素，对超热中子活化分析测定Ｉ和Ｂｒ进行了实验研究，Ｆ，Ｃｌ，Ｂｒ，Ｉ的检出限分别为１０＾－３、７４×１０＾－６，１．７×１０＾－６，７．８×１０＾－６。ＲＳＤ〈１５％。     

围岩对自然伽马测井影响的数值模拟

自然伽马测井主要受地层中自然伽马射线强度的影响,但围岩的吸收系数也会对自然伽马测井曲线产生影响。运用数值积分的方法推导了在伽马光子能量恒定但吸收系数不同情况下有限厚放射性地层伽马射线沿井轴的分布,并据此开展了数值计算。得出了不同层厚条件下,围岩的吸收系数不同于地层吸收系数的情况以及厚度相同、围岩的吸收系数不同对应的理论曲线。直观地表示了它们对地球物理测井的影响,为进一步研究提供了有用的基础资料.     

水及其高压相的研究进展

人们通过喇曼光谱、红外光谱、X射线衍射、中子散射、Brillouin散射等各种方法,在各种条件下(如低温、高温、高压)研究了水的结构性质和相行为.Okhulkov等对常温液态水的能量散射X光衍射(EDXD)研究发现,在0.1～200 MPa,水分子间的OO间距rO-O随压力的升高而减小;之后,rO-O随着压力升高而增大,在400～500 MPa时达到初始最大值;然后,随压力的升高而减小.A.KSoper等通过中子衍射研究发现,液态水与冰一样,也有多形现象.     

中子-热中子测井在煤田测井中的应用

最近,利用美国蒙特公司的系列Ⅲ数字测井仪在山东滕县煤田滕北勘探区实测了10个钻孔。资料表明,中子-热中子测井应用价值很高,地质效果显著。它能有效地划分地层,判断岩性,确定煤层及其结构,观察煤质变化和确定含水层。通过数字处理,还可定量的分析煤质,确定岩性和岩石孔隙度。本文仅就中子-热中子测井曲线的应用谈谈自己粗浅的认识。      

超热中子活化法测定碘和溴

介绍了采用微型反应堆超热中子活化分析膳食样品中Ｉ和Ｂｒ的方法。讨论了热中子屏蔽材料的选择，干扰扣除等问题，计算了不同样品的探测极限及标准偏差。对几种标样进行分析，其结果与推荐值相符。     

An improved method for computer simulation of geochemical neutron activation experiments

A computer method has been developed that simulates gammaray spectra of geochemical thermal neutron activation experiments. The input for the simulation includes the designation of rock type, neutron flux, sample volume and density, irradiation time, time of detection start, duration of monitoring, and number of analyzer channels. The output of the simulation includes either two-or threedimensional computer drawn plots of the resulting (simulated) gammaray spectra. The threedimensional plots (energy vs counts per sec vs time of detection) allow the investigator to observe the apparent appearance and disappearance of photo peaks, annihilation peaks, and pair production peaks of the various isotopes as a function of time. Various combinations of irradiation, delay, and detection times result in various spectral patterns. The resultant patterns accurately simulate the real activation experiments run under the same time conditions. The simulated spectra are useful for identifying peaks obtained from real spectra, helping in radiochemical separation decisions, and, in general, in designing the neutron activation experiment.     

Delineation of Fractures through Acoustic Televiewer Log

Boreholes are the only sources for direct measurements of geological and geophysical characteristics of the shallow subsurface of the earth. Borehole imaging tool “Acoustic Televiewer (ATV)” is an advanced probe, which records 3D image of the bore hole wall and is used to obtain oriented images of bore hole and provides substantial information regarding lithology, structural information, detection of fractures and casing of the borehole. The images are highly sensitive to the presence of fractures, the delineation of which becomes accurate and reliable based on these acoustic images. Features identified on log-derived images can be correlated with core samples or can be used as substitute in the poor core recovery zones. In the present study, ATV log from a deep borehole drilled at Khadi Kolavan in Koyna-Warna region of Ratnagiri district, Maharashtra located west of the Western Ghat escarpment in the Deccan Volcanic province, India, is used for interpretation of structural characteristics of the formation. The same was correlated with other conventional logging methods such as resistivity and full waveform sonic (FWS) as well as core logging and rock quality designations (RQD) which generated new understanding of the basement and basalt cover in this region.     

The spectrum of solar cosmic rays: Data of observations and numerical simulation

Analysis of the relativistic proton spectra of solar flares occurring in the 23rd solar activity cycle derived from data of a worldwide neutron monitor network and numerical modeling both provide evidence for the acceleration of charged particles by an electric field that arises in coronal current sheets during reconnection. The method used to obtain the spectra is based on simulating the response of a neutron monitor to an anisotropic flux of relativistic solar protons with specified parameters and determining the characteristics of the primary relativistic solar protons by fitting model responses to the observations. Studies of the dynamics of the energy spectra distinguish two populations of relativistic protons in solar cosmic-ray events: the so-called fast component, which arrives at the flux front of the solar cosmic rays, followed by the delayed slow component. The fast component is characterized by strong anisotropy and an exponential energy spectrum, in agreement with the spectrum yielded by mathematical modeling of particle acceleration by an electric field directed along the X line of the magnetic field. The slow component, whose propagation is probably diffusive, has a power-law spectrum.     

多井测井解释软件的研制

目前,测井解释技术正逐渐由单井解释向多井解释研究发展。多井解释是基于地震、地质、测井和油藏工程等多种学科的综合解释技术,它有效降低了测井分析结果的不一致性和差错率。本次开发的多井测井解释软件是基于W indows操作系统,专门为测井解释设计的微机测井应用软件包。软件分为数据管理、数值分析、地层对比、连井剖面、储层参数分布共五大功能模块,在生产中为提高测井解释符合率和降低劳动强度提供了技术平台。     

论川北砂岩型铀矿床方解石脉与铀矿成矿关系

对以303和1210两矿床为代表的川北砂岩型铀矿床的野外调查、方解石脉的岩矿鉴定、包裹体测试、微量元素和铀含量分析、脉体与矿化围岩蚀变关系的研究得出:方解石脉由中低温热水充填裂隙形成,热水同时活化汲取围岩中的铀,搬迁到构造裂隙发育、富含有机质的地段再沉淀富集。迭加成矿,川北砂岩型铀矿床为热水改造成因     

高压喷射灌浆构筑垂直防渗板墙围井试验的几个问题

在简要介绍高压喷射灌浆技术原理的基础上，重点介绍了采用高压摆喷灌浆构筑垂直防渗板墙的围井试验情况，详细分析了围井开挖、注水试验及高喷墙体样品的检验结果，并提出了高压喷射灌浆技术在酸性水、动水、超深孔、含有大块石地层等条件下的应用问题。     

基于ArcGIS Engine的工程勘察柱状图绘制系统的设计与实现

柱状图的自动绘制作为工程勘察信息系统的一个重要组成部分,在GIS环境下的设计和实现是文章探讨的主题。这里将基于刚刚推出的ArcGIS 9.0全新开发环境ArcGIS Engine,先论述柱状图绘制系统中“模板”的设计以及以“模板”为基础的柱状图绘制系统的总体结构设计,再详细阐述它们的实现方法,最后总结ArcGIS Engine的一些实用技巧。