The results of measurements of the physical properties of the typical oilsands mined in Higashiyama oilfield are as follows. a. Permeabi ity, 2500 millidarcys; porosity, 30 percent b. Permeability, 600 millidarcys; porosity, 25 percent The oil content of these depleted sands shows 5 percent by volume in the richer parts and 2 percent by volume in the poorer parts. Flow of oil in the reservoir after exploitation has been effected only by gas energy; the shale beds and the small faults have not interrupted the flow of oil in the reservoirs. The recovery of oil by the pumping wells reduced the percentage by volume or oil in the sands to 2.8 perent; secondary recovery by means of the gallerie drainage in the oilsands further reduced this percentage to 2.0 percent.
The characteristics of the fourth curve are described the three electrodes method which is one of the methods of the electrical coring The author plains the thecretical. equations for three layers by use of the elccirc images and calculates the theoretical curves in the case of the formation witch is the cthickness is less than six times pick-up span. And the distance between the potential electrodes can describe the variations in the thin layers chiefly in order to calcula e the forth curve the spacing is 4.5 times pick-up spani the curves are indicated at Figure 2 and 3
It is described the theoretical design of the piles foundation of a derrick. The design must meet the following requirements: that is determine the kind of piles and its arrangement and calculate the load which acts on all the piles and the bearing power of piles which is given by Dorr's formula. Two examples are shown in Fig. 2 and 3.