A new submarine research chamber named "Kuroshio" which belongs to the University of Hokkaido was built in 1951 for the purpose of studying oceanography, biology and fishery visually at the undersea. It was planned and designed by Prof. N. Inoue (Hokkaido University) and R. Oaki (International Marine Engineering Co.), under the guidance of Prof. U. Nakaya (Hokkaido University), with the help of Dr. T. Sasaki (Scientific Research Institute). Most parts of it were constructed by the Tsurumi shipyard (Nippon Steel Tube Co.) and accessories such as window glasses, underwater lightings, guages and instruments were provided by several makers. The "Kuroshio" is 3.15m. in height (to the top of the hatch cover), 3.70m, in length (from the tip of wooden bearer to the end of the direction stabilizer fins) and 1.48m, of outside diameter of the observation chamber, with total weight of almost 5, 000kg, with accessories. It has one main observasion window with controlable reflector, one seabottom observation window and three side and rear windows Lighting equipments are well prepared for submarine observation and for photographying. It is hung down from a mother ship by suspending wire and electric cables for light and telephone will serve as second hunging wire when necessary. Tow or three persons are able to work in the chamber operating instruments, making scientific observations and taking photographs from the window. They always communicate by telephone with the bridge of the mother boat, talking everythings what they saw, what it happened and giving orders to each other. The endurance of staying at the undersea is about 10 hours for 2 persons aided by the oxygen feeder and CO2 absorbing unit. Its safe diving depth is 200m, below sea surface as it is designed to make surveying on the continental shelf, although it is durable under the pressure of 400m, sea depth. The suspended "Kuroshio" is usually slowly propelled by the drifting or slowly moving of mother ship and able to stand still at the sea bottom when the mother ship is anchored. Important scientific results were obtained by the "Kuroshio" since 1951 at various areas around the Japanese islands. Among biological works, observations on "marine snow" (snow flake like suspending aggregates of disintegrating corpses of planktonic micro-organisms) were well done and habitats of many kinds of bottom fishes and benthonic animals, burrows and piles of them were fully recorded. In the field of fishery, behaviers of trawl net fish traps and plankton net under operation, nature of fish culture bed and effects of light for fishing were investigated, while optical and sonologic studies in the undersea and turbid water observation were made in physical oceanography. The present author tried to operate the "Kuroshio" for submarine geological surveying since 1953 and found it to be a very useful tool for the purpose. In the Ishikari Bay of Hokkaido, several types of ripple marks under formation and some mode of occurrence of marine shells were seen at the sea bottom, suggesting us its usefulness on studying marine sedimentation. In the Tsugaru Strait between Honsho and Hokkaido, where a project of railroad tunnel driving is now under planning by the Japanese Government Railway, kinds of rocks and every geological formations exposed on the seafloor were fully identified by naked eye from the window. And it lead us to believe that it will be possible to draw geological route map of the seafloor by continuos, linear observation on the "Kuroshio" by slow moving and even making geological map when routes are effectively selected. This submarine geological work will be done more efficientry in cooperation with bottom rock sampling by dredging method.
When the present writers designed a gas lift installation, they depended on the past experience. Because they have many variables involved in making gas lift calculation. The study of continuous flow gas lift well by F.H. Poettmann and P.G. Carpenter made it possible theoretically to design gas lift installation. The gas lift system is actually in practice at Niigata gas field, Mobara gas field and many other gas fieleds in the country. If writers can apply their theory to designing gas lift well in the gas fields of Japan, the efficiency of gas production from the wells may be increased. The most common type of gas lift method at the gas fields is one in which the gas is injected into tubing and the production returned through the annulus. They studied the gas lift method in which the gas was injected in the annulus and the production returned through the tubing, and the the correlation curve, though essential in their theory, can not be extended to flow through casing size. Making the application of their method, writers must study whether writers can use their method or not. Writers carried out the gas lift tests, in which the gas was injected into the tubing, at 6 inches water well drilled in the Akita University field. The results from the tests were the same as those obtained from the calculation based on their theory. (see Fig. 2) It became clear that their theory could be extended to the gas lift in which the gas was injected into tubing. And writers calculated the correlation factors from the data collected at Niigata gas field, and a plot of the correlation factors versus the product of the hydraulic radius of the annulus and the mass velo city of the fluid is shown in Fig. 3. By using the correlation curve, writers may desigen the gas lift wells in Niigata gas field and may increase the efficiency of the gas production from wells.
"Telnite" prepared in their laboratory by reacting lignites with dil. HNO3 were used as both deterdants and dispersants for oil well cement slurry with favorable results. Judging from the rate of oxidation reactions of lignites, could determine "Telnite" with its best utility for the purposes.
Chemical analysis was carried out for the core samples obtained from R 114 well in the Kurokawa oil field, in 1954. Samples are following eight cores. Tentokuji dark grey silt stone .......................................50m, 100m, 150m in depth. Funakawa black shale .............................................200m, 250m, 300m in depth. Onnagawa siliceous shale ........................................................350m in depth. Andesite ......................................................400m in depth. Specific gravity of wet core samples, water content, color of H2O extraction, Cl-, HCO3-, NH4+, O2 and N2 consumption, SiO2, TiO2, Fe2O3, Al2O3, MgO, CaO, Ignition loss, +H2O, -H20 and organic matter were determined In this core analysis, the most important fact is the correspondence of the boundaries of chemical characters, microbiofacies and lithofacies. The first boundary exists about 150-200m in depth, and the crude oil exists at 150 and 400m deep. It is necessary to survey the whole area of oil-bearing Tertiary basin using the Two geochemical methods, namely analysing the oil field brines and the cores.