A great deal of marine molluscan fossils is contained in the Lower or Middle Pleistocene Nisiyatu sand developed in the northern part of the Boso Peninsula, South Kanto, Japan. The molluscan fossil-coenosis consists mainly of two elements, which are euneritic and subneritic-bathyneritic. The former element is composed of both Kurosio and Oyasio types, and the latter is composed mainly of Kurosio type. Judging from the state of preservation of each fossil, the euneritic Kurosio element is translocated by bottom-current into deep sea-bottom and mixed with subneritic-bathyneritic element, but the so-called euneritic Oyasio and the subneritic-bathyneritic Kurosio elements may be considered to be para-autochthonous. Therefore, it can be easily understood that the so-called eu-neritic Oyasio element in this molluscan fossil-coenosis was the subneritic-bathyneritic dwellers when the Nisiyatu sand was deposited. In other words, the mixture of Kurosio and Oyasio types in the euneritic element is not caused by increase and decrease of warm and cold currents.
The author have been studying about gelations of various low pH. low lime muds after setting at high temperature (125-150°C) for 20 hours. And he found the following facts; (a) There are clear relations between gelations and concentrations of solids (volume % of bentonite or native clay solids) and lime. (b) The good condition can be kept at very low alkalinities and lime concentrations, when the solid contents are at a minimum. (c) The most suitable concentration of lime ranges is about from 5.0 to 8.0 grams per liter. (d) The best concentration of low gravity solids and lime for posthydration is clearly different from that for pre-hydration.
Determination of physical properties of oil sands obtaind at galleries at Higashiyama oil field is valuable for understanding true properties of an oil reservoir because they are not affected by drilling fluids.
In this report, the author discussed whether the theory of multiple-phase flow of gas, oil and water through tubing (by F. H. Poettmann and P. G, Carpenter, members of Phillips Petroleum Company) may be applied extensively to the case of casing flow such as gas well at Niigata field or not.
In 1952 the author described that the performance behavior of Mobara gas field was the results of gravity drive in the report "The Development of Mobara gas field". In this report some more details are explained. The most significant characters of the Mobara reservoirs are generally not very well understood because of the complexities. To explain these conditions in somewhat more detail, it is necessary to use the performance curves in the field being now developed. On gravity drainage, counter-current flow of gas up-dip may become important factor. When water drains down-structure it must be replaced by gas. So that wells high on structure show increase of gas water ratio more rapidly than wells low on structure. The M. E. R. (most efficient rate of production) is about 15, 000-20, 000 m3 gas per day per6, 000, 000 square meters in the case of which water level declines 6 meters per year.