The Sagami River, 110 km long, flows from Mt. Fuji down to the Sagami Bay through the Tanzawa Mountains. The lower course of this river makes an alluvial plain, which is surrounded by Pleistocene hills and terraces (fig. 1). The main subjects and the results obtained in this paper are as follows:
1) To classify the landform of the alluvial plain, and also to disclose the subsurface geology of the alluvial fills by using bore holes: The landform of the alluvial plain is classified as in fig. 1. The basal landform under the alluvial fills is shown in fig. 2, where exist buried river terraces (UT, MT, LT, etc.), buried abrasion platforms (TW and AW), and buried valleys (NV, TV, KaV, etc.). The main buried valley made by the previous Sagami River (SV) cut down to 90 m below sea-level at the mouth of the present Sagami River. The alluvial fills above the basal landform is named “Recent deposits” according to the usage in the Mississippi River plain.
The facies of the Recent deposits are illustrated in the geologic sections of fig. 3-8, the section lines of which are seen in fig. 1. Depending upon these sections, lithostrotigraphic units of the Recent deposits are classified in descending order as the following:
2) To correlate the Pleistocene subaerial river terraces, which inclined under the alluvial surface, with the subsurface buried terraces or valley floors under the Recent deposits ; then to explain the late Quaternary succession of the Sagami River: From the longitudinal section along the Sagami River (fig. 3), it may be said that the steepest river terrace, designated as Mm, is correlative with the Sagami buried valley floor, and also with the submarine shelf of 110-120 m below sea-level. The stratigraphic horizon of the Mm and other subaerial terraces are given within tephra of this region, which were derived mainly from Fuji Volcano situated 60 km west of this region (fig. 9). Using previously measured C-14 ages of the tephra layers concerned, the age of the Mm terraces is counted between 25, 000 and 17, 000 years B. P. Therefore, it seems from fig. 3 that the Recent deposits have been accumulated after the maximum drop of sea-level in the Würm glacial age. Thus it is supposed that the facies change in the Recent deposits represents the change of depositioal environment caused mainly by the ecstatic change of sea-level and also land uplift. The rate of land uplift seems to be rather uniform, and the value of uplift during the last 20, 000 years is estimated as much as 30 meters.
3) To explain a discrepancy between the morphology and deposits of the river, which have natures of ordinary river beds in an alluvial fan, and the surrounding flood plain morphology and deposits, which is of natural levee-backswamp type: It has been said that alluvial plain morphology in Japan is classified into three main types, i. e., alluvial fan, natural levee-backswamp, and delta. Moreover, it is generally accepted that in each type of plain, morphology and deposits of a river bed have characteristic natures corresponding with the natures of morphology and deposits in the surrounding flood plain of the river. That is, a river on an alluvial fan has braided channels and gravelly deposits on the bed, while on a natural levee-backswamp type plain, a river has meandering channels with sandy deposits on the bed. However, the alluvial plain of the lower Sagami River, in its central part, being of a natural levee-backswamp type, nevertheless has gravelly braided channels like on alluvial fans. Why this discrepancy was caused may be explained as follows: in case of this plain, the river flowed into a lagoon or narrow inlet enclosed by the sand barrier of the upper sand (US-f), therefore, the transported muddy materials accumulated in the closed water.

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An area is a spatially organized body of human masses which has a center. It means that our human society has evolved, has grown, and has enlarged economically and socially through mutual human contacts. Man's social, economical activities in an area are realized and carried out through the contacts of plural men. Some of them are daily-life activities such as shopping, amusement, and social intercourse, and some of them are business-culture activities such as conferences, meetings, research societies, and business talks. Such activities of inhabitants as exchange, intercourse, recreation, exploitation, search for valuables, and anti-socialistic activities, are mostly carried on in spatially limited areas. These key bases where human masses gather and contact, the author calls “Central Places”. Whether central places are great or small will be determined by the total number of the inhabitants who contact with each other and the extent of the areas concerned. Central places have a wide range, and vary from the largest one like a metropolis to the smallest one like a rural town where people shop near the railway station or a drive-in by the highway.
Central places are important bases which exercise regulation and render service activities for the inhabitants and the community system. In addition to this, central places can be said to be such mirrors as reflect sensitively the economic, social prosperity and depression of the back-grounds. In the spatial arrangement and the tendency of change of the central places that are nuclei of areas, a certain definite order can be seen. That is because an area, which is the space organized by men, is a systematized body, on which (1) men's natural activity trend, (2) the space-controlling power of an area, and (3) various forms of culture and civilization as their medium term, have been reflected. The order of areas is influenced by many different organizations, but, on the contrary, it has a strong controlling power which regulates the daily lives of inhabitants. The object of this study is to explain the actual state of the order of areas through the changing processes of urbanization which are appearing in the central places. For that purpose, the author first classified the changing processes of areas called ‘urbanization’ into the four patterns, that is, Nuclearization, Urbanization, Metropolitanization, and Megalopolitanization. Then he investigated the characteristics, the areas concerned, the changing contents, and the extent of influence, of each pattern. Through such investigations the author has made strenuous efforts to discover and clarify the essential nature of the order of areas which is governing the whole Islands of Japan.

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The Tsurugizawa gorge locates in the center of the Tateyama-Tsurugidake Range in the Japanese Northern Alps, Central Honshyu. The Tsurugizawa river flows to northward from Mt. Tsurugigozen which is head of so-called glacial cirque, then turns east or north-eastward in the middle reaches, and finally drains into the Kurobe river at the Jujikyo junction.
The upper-most area of this gorge is characterized by the so-called “Tsurugizawa Cirque” as previously reported by Dr. Imamura and others.
A large quantity of debris exists in the head area of the gorge, which is usually designated as “moraine”. The diameter of some debris exceeds five meters. The distribution of the quantity of debris is not uniform along the stream valley in the area. That is, a large quantity of debris accumulates on the right bank of the stream, building up debris-mounds which form rampart, tongue, stage, bank and knob.
The main purposes of this study are to make clear the pushed out direction of debris relating to the topography of valley bottom and the mechanism of accumulation of debris.
In this study, the author utilizes “sedimentary fabric” in order to clear the transported direction of debris. Prior to this investigation, many observations on the sedimentary fabric of recently formed taluses in the Tanzawa Mountains were made to elucidate the relationship between the sedimentary fabric and the mechanism of debris movement.
The major results of the field survey are as follows. The debris in the studied area are composed of two kinds. The upper area is covered with diorite, transported from south-west. The lower area is covered with granite, transported from south. The line of demarcation between the two kinds of rocks is shown by a line from st. 72 to st. 77.
Debris accumulated in the valley bottom are weathered to a considerable degree, but debris recently pushed out from side slope are less weathered than the former.
The sedimentary fabric of the weathered debris shows approximately the same direction in its arrangement as that of the valley bottom. In the both area, the upper segments of weathered debris mounds are partly covered with a large quantity of fresh debris pushed out from the side slope.
Especially, in the lower area, the fresh debris are supplied from slopes facing north-west and or north.
In the valley of the upper area, it is certain that there existed at least two periods of debris formation in the past because both debris-mounds of rampart type and tongue type had deposited on debris mound of stage type.

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