Geoic: an interactive terminal-based geochemical data processing system

Abstract

A series of interactive terminal-based FORTRAN IV programs have been developed for processing and evaluating major and trace element data produced in the analysis of rock samples. The GEOIC system consists of three stages. The first is concerned with the processing of analytical data produced in the X-ray fluorescence (XRF) analysis of fused samples for major elements and pressed powder briquettes for trace elements. In the second stage, the major and trace element results are linked together by a tabulation program which creates an input file for CIPW norm programs. The tabulation program will sort also the analyses into groups according to an 8 character “group identifier” keyword attached to each analysis. Average analyses are calculated also for each group. The tabulation program combines the major, trace and normative data to produce a data base file as well as a tabulated output file for dispatch to a line printer. In the third stage, the data base file serves as the input to interactive programs for graphical and statistical evaluation of the geochemical data. The graphics program allows the user to plot rapidly binary and ternary diagrams for all samples or plotting may be restricted to specified groups or only to the group averages. The statistical program allows the user to calculate various parameters as well as a correlation coefficient matrix for all samples, for selected groups or for only group averages. The group identifier keyword attached by the user to each sample analysis facilitates the division of the suite of samples under study into groups and subgroups. This important feature adds considerable flexibility to the processing and evaluation of data via the tabulation, graphics and statistics programs. The tabulation program will accept also free-format major and trace element data produced by analytical methods other than XRF. The second and third stages of the system may be used, therefore, as a general purpose geochemical data processing and evaluation package.