An Example of Processing Geometric Data from Geological Body on a Personal Computer.
This paper deals with an example of processing geometric data from geological body on a personal computer (NEC PC9801VX21).
Orientation diagrams, being familier to the study in geology, are made by computer graphics. This program has been composed of BASIC.
Large masses consisting of rhyolite and granite occur in the Tateiwa district of Hiroshima Prefecture. For each of joint surfaces observed on the outcrops of these masses, the attitude was determined by measureing the strike and dip. The point diagram and contour diagram of these measurements, which are plotted on the lower hemisphere of equal-area-net, are shown on computer display.
In this conture diagram of the graphics, 16 gardes defining degree of preference in orientation are represented by different kinds of color. Each circle (one percent area) inscribed about each point is painted one by one, then, areas of overlapping other circles are repainted with the color choiced according to overlapping numbers. 16 colors are arranged for the repainting.
The time needed to complete the contour diagram of 100 points is about 10 minutes (with BASIC Compiler).