Showing papers in "Computers & Geosciences in 1980"

TL;DR: DIACHAR as discussed by the authors is a BASIC program for determining the most diagnostic properties of groups or taxa scored for the percentage of presence of presence variables or characters in the groups.

TL;DR: A BASIC program entitled MOSTTYP is given for evaluation of the quality of identification matrices by calculating the best identification scores that an entirely typical example of each group could achieve.

TL;DR: In this article, a BASIC program called OVERMAT is given for determining the extent to which pairs of groups overlap in an identification matrix and critical levels for a noncentral t -statistic, t w, thus permitting significance tests of the overlap determined.

TL;DR: The program described has been of use in comparing physical logs from two boreholes when the aim has been to “line up”, or correlate, the boreholes in order to identify sections where the physical logs show similar patterns.

TL;DR: A FORTRAN IV program (UANOVA) to carry out unbalanced analyses of variance, associated variance component testing using synthesized error mean squares and degrees of freedom where appropriate, and the generation of summary statistics is presented.

TL;DR: GIAPP uses methods of image processing for computing and displaying interactively the results of transformations of geological binary images obtained either by optical or mechanical scanning, or by manual digitization.

TL;DR: A FORTRAN IV computer program for dividing a multivariate sequence of observations into relatively homogeneous segments and either Mahalanobis D 2 or squared Euclidean distance calculated.

TL;DR: A computer program, MRF, has been designed to generate all possible equations for chemical reactions between a chosen set of phases and balanced using the formula Ax = b.

TL;DR: The key idea of the paper is the planarity of bedding surfaces crossing the borehole which imposes a constraint on the crosscorrelation of the four dipmeter traces which is used to good advantage in computing a correlation surface.

TL;DR: Affine transformations alter the length of lines and the angles between them, whereas straight lines remain straight, parallel lines remain parallel, and the ratio in which a point divides a line remains the same.

TL;DR: In this article, a computer implementation of a stochastic model describing changes in a landform during lithologically controlled erosion is described, where the model is a Markov chain in two dimensions where the noise component depends upon the underlying lithologies.

TL;DR: In this article, a method for drawing slope (angle) maps is described, where the contour lines of a topographic map have been expressed in digital form by a digitizer, and the ground surface is considered as a set of partly overlapping trend surfaces.

TL;DR: In this article, three different formulations of the Margules, van Laar, and Scatchard-Hamer types of solvus are used to calculate the miscibility gap between two isostructural phases, and the temperature dependences of parameters are fitted by least-squares regression to a hyperbolic tangent.

TL;DR: The computer program presented here considers a 1-percent spherical counting area on the lower hemisphere, calculates the densities on a spherical grid, develops the contours, and projects them in an equal-angle mode on the meridial plane.

TL;DR: The DISCRIM program is an interactive computer graphics program that dissects mixtures of normal or lognormal distributions using a Tektronix1 terminal in a time-share computing environment.

TL;DR: ForTRAN computer programs are written that are used with Drew, Schuenemeyer, and Root's model to merge the discovery and drilling information and perform the necessary computations to estimate undiscovered petroleum.

TL;DR: A simple method of circumventing the problem of acute problem of computer storage space by optimizing the use of computer central memory and disk space is presented.

TL;DR: A system is described in which digitized line data, such as the boundaries shown on a geological map, are handled within existing software environments for data management and graphic display, which may provide increased flexibility for recording geological data observed in the field.

TL;DR: In this article, the frequency distributions of grades and tonnages of Cu, Pb, Zn, Ag, and Au in Canadian stratiform massive sulphide deposits can be approximated by lognormal distributions.

TL;DR: In this paper, a simulation package written at the Ecole Polytechnique of Montreal, POLYSIM2, is described and several examples of application are presented, such as the estimation of the size of geochemical anomalies, the appraisal of economic ore reserves in an uranium deposit, and finally the evaluation of the fluctuations of the mill-feed grade in a porphyry copper deposit.

TL;DR: A computer program has been developed to simulate the growth of single crystals once these are expressed in Cartesian terms, and it is revealed that the resemblance between the theoretical and recreated models is proportional to the size of the crystals.

TL;DR: In this paper, the geostatistical concept of semivariance is used in VAR to calculate and plot variograms in three orthogonal planes, where distances between all points of pairs are calculated and the vector-angles between them are resolved into components in the X - Y, Y - Z, and Z - X planes respectively.

TL;DR: In this article, a case history of a disseminated gold deposit (Quebec, Canada) in an application of the SIMULHOLE program is presented, as well as simulated histograms and geological sections transverse and longitudinal to the orebody with grades simulated for each synthetic hole.