Unit area discharge of groundwater, Z (m³/day/km²) can be expressed by the following equation,
Z=n/AQ
where Q is the average discharge (l/sec) of well or spring, A is the area (km²) of the surrounding terrain having the same hydro-geologic condition at the well site. n/A is called the coefficient of well distribution or of spring distribution.
This paper deals with the calculation of Z values for Tokai and Chugoku-Shikoku districts with the amount of free groundwater and with that of artesian groundwater. The Z values of artesian groundwater in those districts were plotted on the inter-section chart, Z-Q-n/A diagram, with reference to several well-known land subsidence area. On the diagram, the regression equation based on the method of least squares for 10 sites in the spring area is as follows:
logZ=0.772logQ+2.357
and that for 4 sites in the land subsidence area is
logZ=0.890logQ+2.617
The value of n/A in the land subsidence area was high as 2.5-4. This result suggests that the land subsidence might be due to the overdraft of artesian groundwater rather than that of free groundwater.

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Highly simulated description of the joint system in rock masses can be performed by utilizing new parameter of discontinuity ratio besides the orientation and the spacing of joints. The discontinuity ratio is derived mathematically using field measurements of the spacing of joints.
The general parameters obtained are illustrated on some projects.

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At the beginning, the anisotropic effect to the P-wave velocity affected by the sheeting joint in the weathered granitic rocks have become evident.
(1) P-wave velocity of collected specimens showes distinctly an anisotropy in the weathering grade from nearly 0.6km/sec to 4.0km/sec, but an anisotropy extent of thease values. In specimens, relation of P-wave velocity between horizontal direction and vertical direction is approximated to a circle equatlon 2-1.
(2) On the other hand, P-wave velocity in situ showes an isotropy under about 0.5km/sec, but on anisotropy over this value. In situ, a relation of P-wave velocity between horizontal direction and vertical direction is approximated to an increasing logarithmic equation 2-2.
At the next, under the consideration of an anisotropic effect, analysis of time-distance curves of mirage form has been treated.
The author induced an integral equation 3-12 in order to corrected velocity profile analyzed ae an isotropic medium. This equation was induced from a reciprocal coefficient (k), and equation 2-2.

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