The question of continental shelf has been discussed in the past from the viewpoints of jurisprudence and international law. However, the continental shelf is originally a geographical idea and there are various points requiring clarification through geographical studies. In this essay a general observation will be made in the first place as to the arguments advanced so far in respect to the question of continental shelf and it is then intended to make clear the geographically controversial points of the question of continental shelf taking up, particularly 1) the definition of the continental shelf, 2) relations between land and adjacent continental shelves and 3) the continental shelf and sedentary fisheries
The writer visited the geothermal field at Larderello in Tuscania, Italy in October, 1952. A brief history of progress and the status at that date of utilization of underground vapour in generating electricity are described. Emphasis is given upon the peculiar geological occurrence of the vapour. The vapour seems to have its origin in a magma reservoir which is supposed to be seated at a depth of several kilometers below the surface and to be in a state of progressive cooling.
The metamorphosed axis of the Sakawa folded mountains is traceable into the Dainano metamorphic group. The Taiwan subgeosyncline was brought about on the continental side of this axis. In Taiwan there is no definite evidence convincing the Middle Tertiary orogeny, notwithstanding that it has previously 'been emphasized by many geologists. The change of the geosyncline which took place at that time, may be the westerly shifting of its subsiding axis. Four coal measures intercalated in the marine upper Oligocene and Miocene sediments reveal the repetition of cycles of sedimentation caused by embryonic foldings. For the provenance of exotic heavy minerals in the Neogene sediments the pre-Taiwan dome in the foreland which belongs to the Akiyoshi folded mountains is suggested. The geosyncline was strongly deformed by the Taiwan orogeny in the Plio-Pleistocene epoch and its typical orogenic sediment is the Shokkozan conglomerate. The mountain structure introduced thereby is analysed into the Dainano, Urai and West Taiwan zones with the Kiirun imbricated subzone and the Towen undulated subzone in the northern part of the last zone and their characteristics are pointed out. In addition, brief notes are given on the Daito coastal range and dependent isles later history of Taiwan is discussed in some length.
As a new attempt we tried to apply resistivities of water for ground water survey. The resistivities of water are briefly determined by using a platinum cell connected with a resistance bridge, and seems to express systematically the ground water hydrology in a geologic environment.