CSD SOFTWARE DESIGN FOR FINITE-STRAIN DETERMINATION WITH INVERSE SURFOR WHEEL

Computer simulation of finite-strain determination with the inverse SURFOR wheel may improve the preciseness and efficiency of the strain determination. The CSD softwre, programmed in Visual Basic 5.0 and very simple for its friendly interface, can be used to measure the size of the finite strain and the direction of the long axis of the finite strain ellipse in deformed rocks by means of section images or mineral grain sketches. At the same time, this software can also be used to measure the preferred orientation of the mineral grain distribution. Firstly, the CSD software collects boundaries of mineral grains in the image at all directions from 0°-180°. Secondly, the boundary data dots are distributed in the orientation-boundary coordinate system, and the polynomial curve fitting is made by means of the least-squares. Lastly, the extreme point coordinate of the fitted curve is obtained, and the corresponding strain ellipse is drawn up in line with the coordinate. During the operation of the CSD software, all the collected data of mineral grain boundaries and the resulting fitted curve, and the strain ellipse images can be both visible and saved in the corresponding files.