Excimer laser isotope-ratio-monitoring mass spectrometry for in situ oxygen isotope analysis

A technique using isotope-ratio-monitoring gas chromatography-mass spectrometry (irmGCMS) and excimer laser fluorination for in situ oxygen isotope analysis of silicates is described. The irmGCMS and oxygen extraction line is connected by a newly developed interface, reducing the time for a single analysis to less than 10 min. The precision obtained for δ¹⁸O is similar to what has been reported for excimer laser fluorination using dual inlet systems. δ¹⁸O values of two olivine standards had 1σ precision of ±0.14‰ (n=19 and n=10) and that of Dörentrup quartz had ±0.17‰. Eleven analyses of a large zircon crystal had a precision of ±0.12‰. However, between 300 and 600 nmol oxygen was liberated for a single analysis, equivalent to cylindrical laser holes 250 to 350 μm in diameter and depth. In the future it will be feasible to measure the isotope ratio of cylindrical volumes 150 μm in diameter simply by reducing the volume of the extraction line. While this is still significantly larger than what is possible with ion probes, the ratios obtained by excimer laser-irmGCMS are highly accurate and precise without correction. The value of this technique for in situ oxygen isotope measurements is demonstrated with two rock slabs from metamorphic rocks of the Dabie–Sulu ultra-high-pressure belt, China.     

伽玛能谱测量的应用及资料处理的讨论

本文对伽玛能谱测量参数相关问题的不同观点进行了分析和论述,并介绍了该测量方法在砂岩型铀矿勘查中的应用效果.认为目前适当开展地面伽玛能谱测量,加强航放资料的开发利用,发挥能谱测量方法在砂岩型铀矿勘查中的作用是必要的.     

Hilbert-semblance method for acoustic logging data processing

We suggest a method of multi-element low-frequency acoustic logging data processing which combines advantages of the semblance and phase velocity processing (PVP) techniques, namely, the interference resistance in the former and better accuracy in the latter. The new method is based on point (windowless) semblance by the Hilbert transformation. The introduced concept of phase semblance makes it possible to estimate the signal distribution semblance and the phase. Also suggested are an algorithm for preliminary estimation of formation S-wave slowness from signal group power variations and improved forms of processed data imaging.     

TAD-4数据自动采集和处理系统性能简介

本系统由PZ-80A微型计算机、PZ-80A打印机、HNR-84磁带记录器、显示器和SMR-4土力学参数测试仪(测量轴向变形、钢环变形、体积变形、孔隙水压力)和接口电路所组成。本系统可与三轴剪力仪配套使用,进行固结不排水剪,不固结不排水剪;尤其是配用了我们新研制的电测数字体变仪后,还可作三轴固结排水剪。     

矿井槽波地震数据处理系统GeoCoal软件开发与应用

定位于矿井槽波地震勘探,开发一套针对槽波地震数据的处理解释平台,以期推动矿井槽波地震勘探技术更好地为煤矿安全生产服务。构建了软件设计架构,介绍了软件主要子系统和每个子系统包含的功能模块和软件运行环境,最后进行了部分软件界面和成果的展示。     

区域重力调查资料整理及数据处理

区域重力调查资料整理及数据处理,主要是外业数据采集,按"五统一"计算布格异常值,通过数据处理,将布格异常进行网格化、异常圆滑、异常解析延拓、异常分量转换、异常导数计算,求取异常体埋深,最后实现成果图件。本文通过几年的工作总结,将各种整理计算公式编写出来,为今后工作提供参考。     

An optimized procedure for boron separation and mass spectrometry analysis for river samples

An optimized procedure for the separation of boron from natural river samples and an improved mass spectrometry determination of boron isotopic ratio are presented. The chemical procedure, based on the use of the boron-specific resin Amberlite IRA 743, is especially efficient in separating boron from natural organic matter-rich samples like river waters.The properties of Amberlite IRA 743 have been investigated. The two factors important in determining the boron affinity for the resin are: the pH value and the ionic strength of the solution from which B is to be extracted. A logarithmic relationship between B partition coefficients and pH values is found. High ionic strength significantly lowers the fixation of B onto the Amberlite resin.The knowledge of the factors controlling the affinity of the resin Amberlite IRA 743 for boron enables us to design a simple and miniaturized chemical separation procedure characterized by (i) three chromatographic steps using, respectively, 50, 10 and 3 μl of resin, (ii) no evaporation step between each column, and (iii) final separation of boron from residual organic matter by sublimation of boric acid at 75 °C.Boron isotopic ratios are measured using an improved cesium metaborate technique, with graphite and mannitol. Adequate loading conditions enable us to obtain typical signal intensities of 5×10⁻¹² A for 250 ng of boron. No in-run isotopic fractionation is observed, the external reproducibility for standards processed through the entire chemical procedure, as well as for samples, corresponds to 0.35‰ (±2σ). According to this precision, a slight, but reproducible isotopic fractionation of 0.4‰ is observed for standards processed through the entire chemical procedure whose origin is discussed, but is still unclear.     

地震勘探高分辨率资料处理的挑战与对策

地震勘探发明以来,其分辨率的极限准则一直是波长的四分之一。在探索压缩地震子波方法的过程中,前期最突出的矛盾是信噪比和分辨率;后期的矛盾,则是高分辨率与高保真。与此同时,利用井资料信息,研发了跨越四分之一波长的很多反演方法。这些方法依赖于地震资料的保幅性、地震解释的正确性和井震资料的匹配性;后来又摆脱了井资料的约束,实现了无井约束反演,分辨率达到了反射系数的尺度,此时问题焦点又转化成阻抗信息的可信性。在梳理地震勘探过程中处理部分的相关信息基础上,借助于地震沉积学的思路和方法,提出了不用井资料约束的储层精细分离方法,既超越了四分之一波长的极限,又有了精度的保证。以实际资料为例,给出了四分之一波长范围叠置河道分离结果。这对石油和煤炭企业老资料挖潜,以及新资料开发具有极大的应用前景;特别是对超薄储层超小断距的确定,采空区及废弃巷道的探测等迫切的生产难题,提供了新的解决思路。      

High precision analysis of all four stable isotopes of sulfur (32S, 33S, 34S and 36S) at nanomole levels using a laser fluorination isotope-ratio-monitoring gas chromatography–mass spectrometry

The discovery of mass-independent isotope effects observed in Archean rocks, certain classes of meteorites, and atmospheric aerosols has had profound implications to our understanding of ancient and present atmospheric sulfur chemistry. We present a new technique that takes advantage of continuous He flow isotope-ratio-monitoring gas chromatography–mass spectrometry to achieve precise analysis of all four stable sulfur isotopes (³²S, ³³S, ³⁴S, and ³⁶S) at nanomole level samples. The technique involves fluorination of sulfide (silver sulfide or pyrite), and separation of product gas by gas chromatography and the removal of mass-131 interference by a liquid-nitrogen ethanol slush at − 110 °C. This technique works with an optimum sample size of 100 to 200 nmol with precision for Δ³³S and Δ³⁶S at 0.1 and 0.5‰ (2σ). Samples, as small as tens of nanomole, can be analyzed using this new method. One of the major sources of error in irm-GCMS is found to be tailing of the major ion beam (³²SF₅⁺) onto minor beams (³³SF₅⁺ and ³⁶SF₅⁺), which results in contraction of the measured δ³³S and δ³⁶S scales. This effect is corrected by measuring a series of reference sulfide samples with mass-dependent sulfur isotope compositions. This methodology increases the spatial resolution of the laser ablation in situ analysis and considerably reduces the analysis time as compared with conventional dual inlet methods.     

一种地震资料处理结果的发布策略及其实现

基于C/S和B/S的混合发布模式, 本文给出了一个关于地震资料的“分散计算-集中存储-即时发布”系统解决方案, 介绍了系统框架、相应的开发技术、客户端应用软件及部分实现。实际应用效果表明, 该方案可以提高运行效率, 便于维护和升级, 其可以与一般的信息发布相结合, 实现动态的企业级WEB应用。     

Airborne data processing and analysis software package

The practice of conducting quality control and quality assurance in the construction of data sets is often an overlooked and underestimated task of many research projects in the Earth Sciences. The development of software to effectively process and quickly analyze measurements is a critical aspect of a research project. An evolutionary approach has been used at the University of North Dakota to develop and implement software to process and analyze airborne measurements. Development over the past eight years has resulted in a collection of software named the Airborne Data Processing and Analysis (ADPAA) package which has been published as an open source project on Source Forge. The ADPAA package is intended to fully automate data processing while incorporating the concept of missing value codes and levels of data processing. At each data level, ADPAA utilizes a standard ASCII file format to store measurements from individual instruments into separate files. After all data levels have been processed, a summary file containing parameters of scientific interest for the field project is created for each aircraft flight. All project information is organized into a standard directory structure. ADPAA contains several tools that facilitate quality control procedures conducted on instruments during field projects and laboratory testing. Each quality control procedure is designed to ensure proper instrument performance and hence the validity of the instrument’s measurement. Data processing by ADPAA allows edit files to be created that are automatically used to insert missing value codes into a time period that had instrument problems. The creation of edit files is typically done after the completion of a field project when scientists are performing quality assurance of the data set. Since data processing is automatic, preliminary data can be created and analyzed within hours of an aircraft flight and a complete field project data set can be reprocessed many times during the quality assurance process. Once a final data set has been created, ADPAA provides several tools for visualization and analysis. In addition to aircraft data, ADPAA can be used on any data set that is based on time series measurements. The concepts illustrated by ADPAA and components of ADPAA, such as the Cplot visualization tool, are applicable to areas of Earth Science that work with time series measurements.     

岩盐三轴压缩试验方法及数据处理方式的对比研究

在能源地下储存及废弃物地下处置库的设计、施工、运行中,岩盐的强度和变形特征是极为重要的参数。正确地获得岩盐的强度参数对地下储存库的设计和安全运行具有重要意义。分别选定江苏金坛和湖北江汉岩样作为试验样本,通过三轴压缩试验获得岩盐短期强度和变形的力学参数,比较并总结了以德国为代表的欧美国家与国内试验方法及数据处理方式的异同。同时介绍了德国短期强度试验确定岩盐损伤起始点的方法及其不足,提出了更为精确地确定方法并确定了金坛岩盐损伤起始点。分析发现:对于大变形岩盐,国内测量的强度数据普遍偏高,应采用横截面积修正以及科学应变代替工程应变的度量方式。     

吹扫捕集-气相色谱-质谱法测定土壤中挥发酚的方法研究

文章研究了吹扫捕集-气相色谱-质谱法测定土壤中挥发酚的方法,分析了吹扫捕集各参数对挥发酚测定的影响,优化了吹扫捕集条件和气相色谱-质谱条件.通过与索氏提取技术对比,证明吹扫捕集-气相色谱-质谱法在实际样品检测中具有操作简便、分析周期短、试剂用量少、干扰小等优点,适用于测定沸点较低、溶解度较小的挥发酚,推荐选择经典的索氏提取技术测定沸点较高、溶解度较大的挥发酚.     

Evaluating roadside rockmasses for rockfall hazards using LiDAR data: optimizing data collection and processing protocols

Highways and railroads situated within rugged terrain are often subjected to the hazard of rockfalls. The task of assessing roadside rockmasses for potential hazards typically involves an on-site visual investigation of the rockmass by an engineer or geologist. At that time, numerous parameters associated with discontinuity orientations and spacing, block size (volume) and shape distributions, slope geometry, and ditch profile are either measured or estimated. Measurements are typically tallied according to a formal hazard rating system, and a hazard level is determined for the site. This methodology often involves direct exposure of the evaluating engineer to the hazard and can also create a potentially non-unique record of the assessed slope based on the skill, knowledge and background of the evaluating engineer. Light Detection and Ranging (LiDAR)–based technologies have the capability to produce spatially accurate, high-resolution digital models of physical objects, known as point clouds. Mobile terrestrial LiDAR equipment can collect, at traffic speed, roadside data along highways and rail lines, scanning continual distances of hundreds of kilometres per day. Through the use of mobile terrestrial LiDAR, in conjunction with airborne and static systems for problem areas, rockfall hazard analysis workflows can be modified and optimized to produce minimally biased, repeatable results. Traditional rockfall hazard analysis inputs include two distinct, but related sets of variables related to geological or geometric control. Geologically controlled inputs to hazard rating systems include kinematic stability (joint identification/orientation) and rock block shape and size distributions. Geometrically controlled inputs include outcrop shape and size, road, ditch and outcrop profile, road curvature and vehicle line of sight. Inputs from both categories can be extracted or calculated from LiDAR data, although there are some limitations and special sampling and processing considerations related to structural character of the rockmass, as detailed in this paper.     

适于大规模数据的逆时偏移实现方案

针对海量地震数据逆时偏移所面临的问题和挑战,解决逆时偏移海量计算和海量存储需求在CPU/GPU异构集群平台上实现时的技术瓶颈,重点介绍了基于GPU?RDMA直接通信技术和GPU?Stream流技术的并行算法,形成适合于GPU集群的大规模分布式并行计算,即高密度采集地震数据的三维叠前逆时偏移计算技术;应用高密度实际地震数据测试,计算效率可提升15~40倍。     

A computer-based system for processing geophysical data obtained from boreholes

A diverse set of computer programs has been developed at the Lawrence Livermore National Laboratory (LLNL)to process geophysical data obtained from boreholes. These programs support such services as digitizing analog records, reading and processing raw data, cataloging and storing processed data, retrieving selected data for analysis, and generating data plots on several different devices. A variety of geophysical data types are accommodated, including both wireline logs and laboratory analyses of downhole samples. Many processing tasks are handled by means of a single, flexible, general-purpose, data-manipulation program. Separate programs are available for processing data from density, gravity, velocity, and epithermal neutron logs. The computer-based storage and retrieval system, which has been in operation since 1973, currently contains over 4400 data files. Most of this data was obtained from the Nevada Test Site (NTS)in conjunction with the nuclear test program. Each data file contains a single geophysical parameter as a function of depth. Automatic storage and retrieval are facilitated by the assignment of unique file names that define the storage location of each data file. Files of interest to the user may be located and retrieved by means of a search program that examines the catalog. A convention recognized by all programs in the system is that of a zero ordinate denoting a gap in an otherwise continuous data trace. This convention provides a simple mechanism for editing and displaying data files in an automated and consistent manner.