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1992 | Buch

Use of Microcomputers in Geology

herausgegeben von: Hans Kürzl, Daniel F. Merriam

Verlag: Springer US

Buchreihe : Computer Applications in the Earth Sciences

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Über dieses Buch

This volume 'Use ofMicrocomputers in Geology' is the sixth in the series Computer Applications in the Earth Sciences published by Plenum Press in New York. The series was started in 1969 to publish proceedings of important meetings on geomathematics and computer applications. The first two volumes recorded proceedings ofthe Colloquia (1969,1970) sponsored by the Kansas Geological Survey at The University ofKansas in Lawrence. The third volume was proceedings ofthe 8th International Sedimentological Congress (1971) held in Heidelberg, West Germany; the fourth was preceedings ofthe 8th Geochautauqua (1979) at Syracuse Universityin Syracuse, New York; and the fifth was selected papers from the 27th International Geological Congress (1989) held in Washington, D.C. All meetings were cosponsored by the International Association for Mathematical Geology. These special publications are important in the development of quantitative geology. Papers by a wide range of authors on a wide range of topics gives the reader a flavor for recent advances in the subject -in this volume, those advances in the use ofmicrocomputers. The 24 authors ofthe 15 papers come from nine countries -Australia, Austria, Canada, France, Italy, Portugal, Switzerland, UK, and USA. My coeditor, Hans Kürzl, has given pertinent information on the included papers in the Introduction.

Inhaltsverzeichnis

Frontmatter
Zoneography of Mineral Resources
Abstract
In facing the problem of the exploitation of heterogeneous mineral resources (ore or oil), the question of defining continuous zones exhibiting similar characteristics may arise. A method to approach this question using factorial and geostatistical techniques was developed. It contains three main steps:
(1)
Taking as an input the data matrix (samples x variables), a factorial technique (principal components analysis or correspondence analysis) is applied, giving rise to groups of samples of similar characteristics.
 
(2)
The problem of contiguity within samples of the same group and the number of groups to be retained is solved by expert advice of the geological/exploitation team, based on graphical representation of zones.
 
(3)
Once decided which samples belong to each final group, the boundaries from zone to zone are estimated, using a transitive kriging technique, relying on the geometric variogram.
 
Two case studies are presented to illustrate the method: The first one discusses a polymetallic sulfide orebody located in the South of Portugal, which is to be split into zones feeding different mineralprocessing units. In the second, a Middle East petroleum reservoir is divided into homogeneous zones in order to improve the secondary oilrecovery planning.
The method presented here, combining factorial analysis and geostatistics, is a useful tool for the purpose of delineating zones in heterogeneous deposits of mineral resources. It provides estimates of boundaries between zones based on their geometric structure and gives a reliable basis for further exploitation planning.
H. Garcia Pereira, A. Soares
Teaching and Testing Strategy in Mineral Exploration by Simulation Techniques on Personal Computers
Abstract
The coming of a generation of personal computers with low-cost graphic cards and math processors, gives a new impulse to geological modeling. It now is possible to simulate rapidly and with accuracy complex geological environments with reduced hardware. Such models can be used for teaching mineral exploration or for simulating geological data that can be output easily and used in teaching related techniques like geostatistics or multivariable analysis.
Aside from teaching, several uses of complex geological models are promising such as the modeling of real targets in order to test various strategies of exploration or exploitation. Another use is the experimentation of natural processes such as erosion, dissemination of elements around ore-bodies, folding, faulting, etc...
M. Vannier, R. Woodtli
Computer-Aided Decision Techniques for Hydrogeochemical Uranium Exploration
Abstract
Multivariate analysis has been recognized as a powerful tool in geochemical exploration, but special emphasis also has been given to the necessity to complete adequate preliminary investigation of the data before attempting to use sophisticated data processing and manipulations. The methodology presented here relies on extensive experience with multivariate methods gained from the processing of large case studies coming from surveys carried out by French mining companies using hydrogeochemical uranium exploration. We have developed a robust methodological approach and a set of integrated software available on microcomputers to model the distribution of elements in water analysis and to account for the mixing of the geochemical end-members observed and to tackle the definition of an adjustable modeling of background compositions and of their related anomalies after the removal of the disturbing outliers from the recognized statistical populations has been achieved. The policies used lead to an efficient set of data processing, data integration, and data representation software making it possible to offer practical assistance to the exploration geochemist when faced with decision-making processes.
Patrice Poyet
Estimating the Probability of Occurrence of Mineral Deposits from Multiple Map Patterns
Abstract
By superimposing binary or other types of discrete map patterns on top of one another, a study area can be divided into many small map elements. In this paper, the probability of occurrence of mineral deposits is modeled as a function of the characteristics of such map elements. The two methods discussed for estimating this probability are weights of evidence modeling and logistic regression. Special consideration is given to the effects of selection of study area and map elements for a deposit type, intensity of exploration and spatial autocorrelation effects.
Frederik P. Agterberg
Use of a Laptop Computer and Spreadsheet Software for Geophysical Surveys
Abstract
The use of a laptop computer and spreadsheet software have been introduced to geophysical field work for data acquisition, logging, reduction, and plotting. This is a helpful method for many types of geophysical problems, and can support the geophysicist in the field to understand what is happening as the survey progresses. Examples are given of the application to seismic data acquisition, gravity data reduction, and gravity modeling.
Robert S. Sternberg
A Program for Petrophysical Database Management
Abstract
The personal computer program ROCKBASE based on dBASE IV is presented. The aim of this menu-driven and mask-oriented interactive program is the management of data from irregularly distributed field samples that are measured in the laboratory. Statistical modules such as calculation of mean values are offered, but the main purpose of ROCKBASE is the preparation of the data for graphic output. As an interface the ASCII format enables full compatibility with commercial graphic packages. It is shown that thematic maps of an investigation area can be produced with little expense.
Bernhard B. Holub
Artificial Intelligence Tools and Techniques for Water-Resources Assessment in Africa
Abstract
This paper presents the development of a hydrogeological expert system able to handle the drilling location problem within the scope of village water-supply programs. This work is based on the experience the authors gained from thousands of drillings carried out in fifteen African countries. The cognitive model comes from the practical know-how acquired from real-world programs, from original statistics and probabilistics analyses showing connections between data collected during the drilling-site selection and hydrodynamic parameters registered in the borings and from the research the authors carried out in the artificial intelligence field to propose a comprehensive knowledge modeling framework. The paper includes a description of the specific knowledge involved in the drilling location process. Relevant hydrogeological parameters recognition and examples of advanced computer knowledge modeling methods are presented. First the rules of thumb and the interpretative frames retained for the cognitive model are described, then the characteristics of the HYDROLAB expert system devoted both to computer-aided decision and to computer-assisted learning support.
Patrice Poyet, Michel Detay
Hydrodat®: A Package for Hydrogeochemical Data Management
Abstract
Hydrodat®: is a database system with reference to phreatic and running waters (more generally to liquid and condensate phases) and gas phases. This database system was written for personal computers running MS-DOS.
The three principal data files for physical and chemical characteristics which the program runs (one for phreatic waters, one for stream waters, and one for gases), the calculation routines—some from the literature, others specifically processed—and the graphic elaboration (available through “Grapher” and “Surfer” of Golden Software) are controlled by procedures using mainly dBase IV language of Asthon Tate.
The following points indicate the possible fields of investigations supported by the use of the database:
(1)
fluid’s geochemistry;
 
(2)
hydrochemical prospecting;
 
(3)
geothermics;
 
(4)
volcanology;
 
(5)
environmental control;
 
(6)
monitoring of industrial fluids.
 
The program requires a minimum configuration of 640 Kb of RAM memory and is supported entirely by window-menu and window-help instructions.
A. Minissale, G. F. Buccianti
Minident — Some Recent Developments
Abstract
Minldent is a command-driven program developed originally on a mainframe and now ported to a PC. Since its initial description, a substantial amount of new data and several new features have been added. In addition to information published on new mineral species, data have been included for about 700 presently unnamed minerals. A subset facility also has been added, as well as an extensive synonymy which provides abbreviated information and source references for some 1500 synonyms, varieties, discredited minerals and species of dubious authenticity. A full mineral classification scheme also has been included. Minldent-PC requires at least 560 kbytes of usable RAM, one 32 Mbyte HD drive and a math coprocessor.
Dorian G. W. Smith, Heida Omoumi
Microcomputer Application of Digital Elevation Models and Other Gridded Data Sets for Geologists
Abstract
Personal computers have the disk storage capacity, processor speed, and color graphics displays necessary to manipulate and display large gridded data sets recording elevations, bathymetry, gravity, and magnetic information. These gridded data sets can be used for general terrain analysis, specific geologic calculations, or as the base for a geographic information system. Standard microcomputer hardware lets geologists evaluate, compare, and use data sets with hundreds of thousands of values.
Peter L. Guth
Reusable Code Works!
Abstract
Personal experience in microcomputer applications programming for statistical analyses and graphic displays has proven the value of reusing code. Reusing code has been determined to increase software reliability, increase programmer productivity, and decrease development cost.
Fred J. Gunther
A PC Statistical Package for Field Acquisition and Analysis of Two-Dimensional Orientation Data
Abstract
We describe a newly developed PC statistical package which, in conjunction with a suitably designed laptop or rugged field computer, can be used by practicing geoscientists collecting orientation data in the field. Potential users include structural geologists, field mappers, sedimentologists, and any scientists gathering orientation data. This paper illustrates how the package might be used in practice, in summarizing individual sets of measurements and comparing and combining the summary values from the various sets.
N. I. Fisher, C. McA. Powell, A. Gelin, D. McP. Duncan
A Simple Method for the Comparison of Adjacent Points on Thematic Maps
Abstract
A simple method is outlined for comparing adjacent grid points that have been measured for a series of maps. It is generalized and can be calculated for different types of maps where the original data are continuous or discrete. Either original or standardized data can provide the input information; standardization expresses the various maps in the same units. Next, similarities or differences are computed for all adjacent points from east to west and from north to south on the grid. The coefficients computed include correlation coefficients, Euclidean distances, and Mahlanobis distances; however, other statistics could be employed where appropriate. The coefficients then are plotted on the grid and contoured to depict the distribution of similarities and differences. Various patterns of similarities and differences between the points are shown by different coefficients and standardizations which can be related to geologic features underlying the original data. The maps of the point-to-point comparisons are suitable for subsequent study with other methods such as trend surfaces, filtering, or Fourier analysis. The example given is based on five structure contour maps from the Paleozoic of Kansas.
James C. Brower, Daniel F. Merriam
Map Integration Model Applied in Site Selection
Abstract
Site selection is a location dependent decision-making task, and it is carried out traditionally by overlying various types of maps and attempting to assimilate number of factors into a composite picture. Geologists may be involved in various site selection jobs such as: exploration, environmental studies, construction, and drilling-site selection.
Such a decision can be one of the two types. The first is the unstructured decision—that is based on experience and an overall understanding of the problem. The second type of decision involves a certain amount of precise data and an algorithm to process it, so that a definite or structured decision can be reached. Analysis of the elements of a geologic problem identifies the spectrum the problem belongs. Structured (well-defined) versus unstructured (ill-defined) decision making for site selection will be discussed. To keep the location dependency of variables and taking them into account during the process of decision-making, the variables treated in layers or maps. A map integration model will be introduced that carries the decision-making task and results in the most suitable location.
Elahe Tabesh
Analysis of Space and Time Dependent Data on a PC Using a Data Analysis System (DAS): A Case Study
Abstract
The program system DAS (Data Analysis System) is designed for the interactive graphical analysis of spatial data on the PC. It has no special features for the treatment of spatial time series but it is so flexible that it can be used for the analysis of such data. Some properties of the program and a case study on pollution data in Austria are presented to illustrate its capabilities.
Rudolf Dutter, Gerald Karnel
Backmatter
Metadaten
Titel
Use of Microcomputers in Geology
herausgegeben von
Hans Kürzl
Daniel F. Merriam
Copyright-Jahr
1992
Verlag
Springer US
Electronic ISBN
978-1-4899-2335-6
Print ISBN
978-1-4899-2337-0
DOI
https://doi.org/10.1007/978-1-4899-2335-6