The purpose of this article is to clarify the basin building movement in the Osaka Plain and it's activity, and to know the geomorphological significance through the geomorphology of the Late Pleistocene hills ;and terraces. The region with which the author mainly dealt is so narrow that an intensive study is permitted. The results brought by this investigation are expected to be suggestive and useful for further studies of the Osaka Plain in this line. With a view to studying by this way, the marked geomorphological evidences in the surrounding areas are taken account of in this discussion.
Eustatic movement is considered to be negligible in the inquiry into the formation of the terraces in this plain. The terraces and the plateforms are so discontinuous and variable that they can not be brought into proper correlation. The tectonic significance in reasoning the geomorphology of the hills and the terraces is justified by the geological structure which accords to the landform.
The hills and terraces in the Osaka Plain are composed of the Osaka Group, Pun-Pleistocene, which was accumulated in the Osaka Basin. The basin building movement has developed with flextures, folds, reverse faults and overthrusts. The Osaka Group abuts against the slopes of the mountains around the plain, and is folded, faulted or disturbed. Indulatory deformations of various scale, some of which areclosely connected with the structure, disturbed in one way, or modified the basin building movement ire the other way.
The highest part of the hills, called the Hilly Surface in this artiele, is maintained by the uplifting structure of folds and flextures. The crustal movements indicated by the geological structure are considered to have been still active after the formation of the Late Pleistcene terraces in the southeastern region.. The geomorphological surfaces are regarded as an outcome of the basin building movement, according to which were developed the erosional surfaces in the uplifted part on the mountainous side and the the accumulative surfaces in the depressed part. The last figure (Fig. 8) schematically shows the process of the hills and terraces.
The surfaces in the southeastern part of the Osaka Plain are divided into the Hilly Surface, the Kl Surface, the K2a Surface and the K2b Surface. The Hilly Surface of the most variable relief occupies the areas on the mountainous side. The height of it ranges from 80m to 200m.
The K1 Surface was developed by the continuing crustal movements. It divides into the erosional surface among the Hilly Surface and the accumulative surface on the lower side. The K2a Surfsce was formed in the same manner as the K1 Surface. The fluvial terraces in the southeastern part of the Osaka Plain, almost belonging to the K2a Surface, cut through the hilly lands of the Hilly Surface and the K1 Surfaces. As with the K1 Surface, the terraces of the K2a Surface transform into accumulative surface downstream in the area with straightforward streams into Osaka Bay. The accumulative surface is slightly dissected by the K2b Surface. The Figure 1 shows the location of these surfaces.

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As a part of study on urban functions and areas, the author treated with a daily circulation of labor force getting into and out of cities which he termed “Urban Labor Force Balance.” In order to make a preliminary observation of the urban labor force balance in Japanese cities, 119 cities were sellected out of 238 cities in all with population of 50, 000 and more. As a result of it, it is characteristically recognizable that the supplying and movable type of cities in their labor force movement distribute around some big cities or metropolitan centers (Fig.1). Examplifying with 35 cities around Tokyo (ward area), therefore, as. one of those centers, two ratios, percentage of out-commuters to the central city Tokyo among the total out commuters and that of resident workers among the total workers, computed about each of those surrounding cities, were found themselves inversely proportionate and proportionate respectively to the time distance from central city Tokyo. And the deviations from those general inclinations are regionally grouped (Fig, . 2&3). Though it is hard to get a causal explanation for those groupings, they seem to be conditioned with whether having comparatively influential big working places in each city or in the vicinity.
Interconnections through labor force flow among cities around Tokyo have major groups as excluded those to and from Tokyo, Yokohama, and Kawasaki; they are Shonan (southern suburbs). Musashino (western suburbs), Northern, Eastern suburban groups, and also Northern Kanto group. We can scarcely say, therefore, that metropolitanization in Tokyo Metropolitan Area has reached the stage as disorganized some local groups of labor force movement formed among cities surrounding the metropolitan center. Another peculiar feature of labor force balance in those surrounding cities is that the percentages of lab-or force supplied to them from urban settlements with population more than 50, 000 of all labor force influx decrease as the time distance from Tokyo increases, while contrary to it the percentages of laborers from rural settlements with population less than 50, 000 increase. It is probably because the former percen tages are proportionate to the urban population density decreasing as the time distance from Tokyo becomes greater.
Thus the metropolitan area of Tokyo shown as Fig. 8 was declineated from the viewpoint of labor force balance of its surrounding cities the core of which contains Funabashi, Ichikawa, Matsudo, KawaguChi, Urawa, Musashion, Mitaka, and Kawasaki cities centering Tokyo (ward area).

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[in Japanese]

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