Clustering and visualization of earthquake data in a grid environment

We present a web client-server service WEB-IS, which we have developed for remote analysis and visualization of seismic data consisting of both small magnitude events and large earthquakes. We show that the problem-solving environment (PSE) intended for prediction of large magnitude earthquakes can be based on this WEB-IS idea. The clustering schemes, feature generation, feature extraction techniques and rendering algorithms form a computational framework of this environment. On the other hand, easy and fast access both to the seismic data distributed among distant computing resources and to computational and visualization resources can be realized in a GRID framework. We discuss the usefulness of NaradaBrokering (iNtegrated Asynchronous Real-time Adaptive Distributed Architecture) as a middleware, allowing for flexibility and high throughput for remote visualization of geophysical data. The WEB-IS functionality was tested both on synthetic and the actual earthquake catalogs. We consider the application of similar methodology for tsunami alerts.     

Remote data analysis, visualization and problem solving environment (PSE) based on wavelets in the geosciences

We discuss here the issues faced by earth scientists in analyzing and visualizing large datasets over a GRID-like setup from a client-server perspective. We approach this problem by using a remote, web-based visualization and data analysis framework, called WEB-IS, and by employing second-generation wavelets as a means for reducing the amount of data transferred and for extracting coherent features in complex geophysical flows and surface faulting patterns. As an example, we describe how onboard processors on satellites can function as a server for beaming down extracted information to the client computer on the ground, thus exemplifying WEB-IS as a viable middleware on a GRID network for geosciences.Reviewed by: Prof. I.D. Clemens, Prof. L. Hanyk     

Ubiquitous interactive visualization of 3D mantle convection using a web-portal with Java and Ajax framework

We have developed a new strategy and espouse a novel paradigm for large-scale computing and real-time interactive visualization. This philosophy calls for intense interactive sessions for a couple of hours at a time at the expense of storing data on many disk drives during regular or heroic runs on massively parallel systems. We have already carried out successfully real-time volume-rendering visualization by employing hundreds of processors for a grid with over 25 million unknowns. Both Cartesian and spherical 3D mantle convection are visualized. The volume-rendered images are viewed on a large display device, with many panels holding around 13 million pixels. We will employ a software strategy involving an hierarchical rendering service, which will have as software an Ajax interface for interactive visualization of large data sets on many different platforms from desktop PC’s to hand-held devices, such as the OQO and the Nokia N-800. An option for stereo viewing is also implemented. We have installed a user interface as web application, using Java and Ajax framework in order to achieve over the Internet reasonable accessibility to our ongoing runs. Our goal is to expand the array of interactive devices, which will make it feasible to carry out ubiquitous visualization and monitoring of large-scale simulations or onsite events and to allow for collaborations across oceans.     

Web-based service of a visualization package “Amira” for the geosciences

Amira is a powerful three-dimensional visualization package that has been employed recently by the science and engineering communities to gain insight into their data. We discuss a new paradigm for the use of Amira in the Earth sciences that relies on the client-server paradigm. We have developed a module called WEB-IS2, which provides web-based access to Amira. This tool allows Earth scientists to manipulate Amira controls remotely and to analyze, render and view large datasets through the Internet without regard for time or location. This could have important ramifications for GRID computing.     

高密度电法勘探数据三维处理技术及城市勘察中的应用

在以往的高密度数据反演解释过程中,将地质结构简化成二维,通过地电断面图、切片图进行分析.实际上,地质体具有三维地电结构,二维反演难免会受到旁侧效应的影响,二维图件也不能清晰直观地反映地质体的空间分布情况.本文以某陶瓷厂空洞探测为例,利用实测资料构建三维数据场,在反演参数优化的基础上,选择基于最小二乘法的三维反演技术对数据场进行处理,将反演结果利用三维可视化技术显示出来,对采空区位置及空间形态给出结论.研究结果显示,三维处理技术能够从空间上,多手段、多视角分析物探数据,有效地消除了旁侧效应的影响; 物探结果直观清晰地呈现出空洞的分布位置、范围以及空间特征,与钻探结果吻合较好.     

Visualization of multi-scale dynamics of hydrous cold plumes at subduction zones

Recent increases in the computational power of high-performance computing systems have led to a large gap between the high-resolution runs of numerical simulations—typically approaching 50–100 million tracers and 1–5 million grid points in two dimensions—and the modest resolution of 1–2 million pixels for conventional display devices. This technical problem is further compounded by the variety of fields produced by numerical simulations and the limited bandwidth available through the Internet in the course of collaborative ventures. We have developed a visualization system using the paradigm of web-based inquiry to address these mounting problems. We have employed, as a case study, a problem involving two-dimensional multi-scale dynamics of hydrous cold plumes at subduction zones. A Lagrangian marker method, in which the number of markers varies dynamically, is used to delineate the many different fields, such as temperature, viscosity, strain, and chemical composition. We found commercially available software to be insufficient for our visualization needs and so we were driven to develop a new set of tools tailored to high-resolution, multi-aspect, multi-scale simulations, and adaptable to many other applications in which large datasets involving tens of millions of tracers with many different fields are prevalent. In order to address this gap in visualization techniques, we have developed solutions for remote visualization and for local visualization. Our remote visualization solution is a web-based, zoomable image service (WEB-IS) that requires minimal bandwidth while allowing the user to explore our data through time, across many thermo–physical properties, and through different spatial scales. For local visualization, we found it optimal to use bandwidth-intensive, high-resolution display walls for performing parallel visualization in order to best comprehend the causal and temporal relationships between the multiple physical and chemical properties in a simulation.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s10069-004-0017-2     

三维可视化及物探新技术在矿山接替资源勘查中的应用——以铜陵狮子山矿田为例

在矿山发现和勘查过程中往往积累了大量地质、物探等资料,随着地质体三维可视化和物探新处理方法的发展,利用这些方法对已有资料进行深度挖掘与开发可以提炼出新的有利找矿的信息,避免工作量的重复投入,可为矿山接替资源勘查提供有力的技术支持.本研究以铜陵狮子山矿田为例,收集了其勘探阶段积累下来的地质钻探及物探资料,采用地质体三维可视化建模技术对这些资料进行了二次处理,建立了冬瓜山铜矿的三维矿床模型.在可视化环境下,分析了矿体与各成矿地质要素之间的关系,结合新处理方法对已有重磁资料再处理获取的信息,圈定出了寻找同类矿床的靶区一前冲靶区,并采用EH-4等物探方法进行了验证,通过钻探验证表明,采用三维可视化、物探处理新方法对已有资料进行深度挖掘与开发,不但可以为矿山接替资源勘查提供找矿信息,还能节约大量时间和资金.     

人机联作重磁资料解释方法的研究

人机联作模拟反演可以充分利用一些已知的地质地球物理信息,充分发挥人的智能作用,提高地质解释效果。本文利用二度、二度半多边型重磁模型,在IBM微机上初步实现了重磁人机联作解释系统。     

基于GPS技术的大型结构建筑物动态监测

在回顾传统的结构物震动和位移测量方法的基础上，详细阐述了采用GPS进行大型建筑物动态监测的原理、方法。介绍国内外典型的动态监测实例，提出了监测数据的管理与可视化方案，对未来大型结构建筑物动态监测的技术进行了展望。     

3-D geochemical interpolation guided by geophysical inversion models

3-D geochemical subsurface models, as constructed by spatial interpolation of drill-core assays, are valuable assets across multiple stages of the mineral industry's workflow.However, the accuracy of such models is limited by the spatial sparsity of the underlying drill-core, which samples only a small fraction of the subsurface.This limitation can be alleviated by integrating collocated 3-D models into the interpolation process, such as the 3-D rock property models produced by modern geophysical inversion procedures, provided that they are sufficiently resolved and correlated with the interpolation target.While standard machine learning algorithms are capable of predicting the target property given these data, incorporating spatial autocorrelation and anisotropy in these models is often not possible.We propose a Gaussian process regression model for 3-D geochemical interpolation, where custom kernels are introduced to integrate collocated 3-D rock property models while addressing the trade-off between the spatial proximity of drill-cores and the similarities in their collocated rock properties, as well as the relative degree to which each supporting 3-D model contributes to interpolation.The proposed model was evaluated for 3-D modelling of Mg content in the Kevitsa Ni-Cu-PGE deposit based on drill-core analyses and four 3-D geophysical inversion models.Incorporating the inversion models improved the regression model's likelihood(relative to a purely spatial Gaussian process regression model) when evaluated at held-out test holes, but only for moderate spatial scales(100 m).     

航空物探空间数据三维模块开发

剖面平面图和等值线图作为航空物探数据的成果展示图,专业性很强,而三维可视化技术的迅速发展,为物探数据成果表达提供了新的技术.笔者主要完成了以下任务:①完成了航空物探网格数据向栅格影像的转换,实现了航空物探空间数据的三维显示及相应三维显示效果设置;②获取线段在多表面模型上的剖面线,基于GDI+绘图实现多表面平面剖面线的绘制;③设计了交互式飞行和沿路径飞行两种三维浏览方式,基于实际飞行中飞机的三个速度参数和最低安全高度,提出沿路径飞行中路径平面设计和高度设计的算法,避免了动画画面不连续或飞入地下等不现实情况的发生.     

基于数字地球平台的地质钻孔三维模拟与可视化

研究了地质钻孔信息的管理和可视化技术,提出了一种在数字地球平台中进行城市钻孔信息模拟和可视化的方法。该方法基于一个统一的钻孔数据库标准,首先将钻探点位信息和地层分层信息组织成具有不同细节层次的钻探点位模型、钻孔分层散点模型和钻孔管段模型,然后构建基于细节层次模型的海量钻孔信息多尺度表达机制,最后将这些模型加载到数字地球平台中进行可视化及查询、分析。在上海市的应用实例显示,该方法实现过程简单、自动性高,生成的模型易于在国际互联网上进行分发、集成与共享。该方法的应用将有助于地质工作者向其他科技人员以及社会公众展示、分发自己拥有的钻孔信息,为以钻孔数据为代表的城市地质信息的社会化服务奠定基础。     

基于开源GIS构建矿区物探资料二维可视化软件

国外优秀的综合物探资料处理解释软件一个共同优点是面向用户提供一个功能强大、界面友好、可视化强的数据管理模块。笔者在分析了Winglink、Emigma、Geosoft等软件中数据管理模块的优缺点基础上,从解剖、仿制的角度出发,提出了以开源GIS平台为核心的快速构建综合物探资料二维可视化管理模块的技术方案,并详细阐述了其相关功能模块的技术原理和实现过程。实际应用效果表明,本技术方案是可行的,且具有低成本、高效率、低技术难度、开放性强的优点。     

一种基于物性数据的深部三维地质建模方法

地质采样信息不足是制约深部三维地质建模的重要因素, 深部物性探测数据由于其易于获取而能够有效形成可视化模型.结合这一特点, 在地质调查项目工作中探索出了一种基于物性探测数据的三维地质建模方法.它首先利用岩石样品物性测量实验数据提取出物性参数及其对应地质属性的映射关系, 然后将不同地球物理方法所获取到的物性数据进行综合建模并解释, 最后将解释后的可视化模型转换为地质三维模型.实践证明, 该方法能够针对性地解决项目中的一些深部地质三维建模问题.      

墨西哥湾海上泄压和压力封存箱化的四维地震监控

在油藏开发和油藏工程方面，三维地震勘探技术正在起着越来越重要的作用，每年都可发现三维地震在这些方面的应用，特别是时间延续的三维地震即四维地震技术使得用计算机来监测油田开发的日子已为期不远。也许这种监测技术不久将成为石油工业的标准。野外生产监测仪可以源源不断、近真时地把地层压力、温度和流体的变化送到控制中心。在控制中心，油藏模拟、弹性波和声波的正反演将告诉我们有关这些变化的答案，进而通过先进的计算机视像显示来控制油藏的开发。文中我们应用在哥伦比亚大学Ｌａｍｏｎｔ－ＤｏｈｅｒｔｙＥａｒｔｈＯｂｓｅｒｖａｔｏ－ｒｙ发展的四维地震振幅分析技术分析了墨西哥湾ＥｕｇｅｎｅＩｓｌａｎｄ３３０／３３８块中的沙岩油气藏ＬＦ。初步结果显示，在类似北墨西哥湾的盆地中，连续三维地震反射振幅的变化可以直接显示第三系盆地中的碎屑岩油气藏的存在。井Ａ－８ＳＴ的成功钻探也证明了四维地震振幅的变化可以有效地帮助寻找油气藏。目前，我们正利用现有的测井资料结合地震正反演技术进一步分析振幅的变化。我们相信这种应用重复三维地震勘探的四雏地震技术将在油藏开发和生产中起着越来越大的作用。     

青藏高原地球物理研究中几个重要问题之我见

青藏高原的地球物理研究是深化认识高原本体和东亚壳、幔结构、隆升机制和大陆动力学响应的基础,故为中、外地球科学家们所瞩目。主要讨论以下3个方面问题,即问题的提出与背景;当今青藏高原地球物理研究中的核心科学问题;当前地球物理学要做些什么。研究结果表明,第一,在青藏高原地球物理研究中只有在清晰思路指导下取得高分辨率的数据才能反演,并刻画其壳、幔的精细结构;第二,青藏高原壳、幔结构存在分区特征,特别是地壳低速层、力学作用、深部物质运移、多要素约束下的物理-数学模拟及陆-陆碰撞动力学响应进行量化研究;第三,当今在青藏高原地球物理研究的核心问题是地球内部物质和能量的交换、圈层耦合及其深层动力过程。中国地球科学家们应当清晰地认识到,青藏高原地球物理研究乃是中国地球科学家摘取“桂冠”的一个契机,必须走自主创新之路,建立起具有中国地质科学特色的理论和模型。     

三维城市地球物理数据管理与服务系统框架

为实现地球物理数据对城市发展提供数据支持, 以3D GIS作为基础平台, 从数据与信息管理、多方法综合处理与显示、成果的三维可视化表达及信息发布等4个层次阐述了三维城市地球物理数据管理与服务系统框架的构建; 数据与信息管理子系统是整个系统的基础, 提供数据基础.GIS支持下的第2层次作为数据显示和多方法交互综合处理的工具而存在, 并为成果信息表达提供基础.后2个层次实现城市地球物理成果数据的展示功能.第3个层次是对成果数据的三维再现, 而第4个层次则通过Web来发布成果信息.在构建三维城市地球物理数据管理与服务信息系统时, 存在2个方面需要解决的问题: (1) 要实现多期次海量的城市地球物理数据的一体化管理问题.提出了以地球物理勘探点、线作为多方法数据融合的基础, 分层次、专题按要素的方式建立多维数据库, 以达到对数据的统一管理. (2) 成果信息的可视化问题.为了在三维空间中再现成果数据, 将地球物理形式的数据转换成地质形式, 设计了一个以线框模型为基本思想来表达三维地质模型的数据模型.将提出的系统框架结合华北某地区进行了应用, 取得了较好的效果.