Fault density and “fault dimension” were measured to each dominant fault direction in some fields of Neogene sedimentary rocks and granitic ones.“Fault dimension” is expressed here as with the displacement of the fault U, fracture width W and fault length L. The linear relations were recognized among these values on the log-log co-ordinates.
In relation to the fault density along the scanline, Poisson's distribution was confirmed by the fault survey. And the frequency-fault dimension curve was in general agreement with the theoretical log-normal distribution.
Total amount of displacements was sometimes found to be large and relatively large faults were often found, in the part of high fault density. These geological features of the fault distribution are explained by the numerical deformation analysis for the continuous rock body with the conbination of elastic dislocation theory and FEM.
Monte Carlo simulation utilizing the poisson's distribution leads the distribution of the position of faults along the scanlines in the objective area and above mentioned numerical deformation analysis can put the fault size on each synthesized fault position.
These ideas were extended to some fields and the distributions of the discontinuities in the rock mass were well estimated in the restricted area described on this paper.