On the longitudinal profile of the terraces of the Musashino Diluvial Upland along the River Tama (Fig. 2), the author fixed his eyes upon the phenomena that the Musashino terrace surface is parallel to the Tama river-bed and the Tachikawa terrace surface crosses both of them, that is, in the west of this region the Tachikawa terrace surface covers the Musashino terrace surface and forms a storied composite fan, in the central part it becomes a fluvial terrace below the level of the Musashino terrace, and in the east it is buried under the Tama river-bed. Then, he thought that these phenomena represent the earth movents of the upland as follows: By the time of formation of the Tachikawa terrace surface after the formation of the Musashino terrace surface, the Musashino Upland, taking an immovable center in the neighborhood of the intersection of the Musashino terrace surface and the Tachikawa terrce surface, tilted downward toward upstream. To the west of the intersection, therefore, the Tachikawa terrace gravels rested on the Musashino terrace and formed there the storied composite fan, while to the east of the intersection the river forming the Musashino terrace surface rejuvenated and formed the Tachikawa terrace surface below the level of Musashino terrace surface, so that their relative height was increased downstream. Up to the present after the formation of the Tachihawa terrace surface, the Musashino Upland has tilted upward toward upstream, and so the Tachikawa terrace surface is steeper than the present river-bed.
However, it is required to calculate the quantity of the tilting of each terrace surface quantitatively in order to study that the terrace topography was formed by whether eustatic movement or earth movement. To solve this problem, the author thought out the following method so as to know a Distance-Altitude Curve of the original river-bed (a graded profile of the river when the terrace surface was a river-bed).
On a graded river, it is assumed that H is the altitude of the river-bed at a locality, x is the distance from the starting point to the same locality, and γ is the constant of integration. Transforming the theoretical formula by S. Shulits, the Distance-Altitude Curve of the river-bed can be expressed as:
H=Ae^kx+γ H>0, A>0, k<0………………………………………………(1)
in which e is the base of natural logalithm.
Differentiating this equation by x, the Distance-Gradient Curve which represents the relation between the gradient and the distance becomes:
S=σe^kx S<0, σ<0, ………………………………………………………………(2)
On the other hand, the Distance-Grain Size Curve which represents the relation between the median diameter G, read from the cumulative curve drawn by the weight percentages of size composition with class units in phi terms, of the fluvial deposits on a graded river and the distance x from the starting point can be shown after H. Sternberg as:
G=ae^bx G>0, a>0, b<0………………………………………………………(3)
Transcribing the equation (3), and incorporating it into the equation (2), we obtain an equation for the Grain Size-Gradient Curve which represents the correlation between the gradient S and the median diameter G as follows:

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Situated within the so-called Green Tuff Region, or an orogenic zone since Miocene, Uonuma District has experienced very active crustal movements even in the Quaternary Era. It is the object of this article to investigate the relation between the geomorphic development and the crustal movement of this district.
Geomorphologically, Uonuma District is divided into four parts running in the direction of NNE_??_SSW, that is, Echigo Mountain Range, Muikamachi Basin, Uonuma Hills and Tôkamachi Basin from east to west. Uonuma Hills and Tôkamachi Basin are an anticlinal height and a synclinal basin respectively, in a folded region of the Niigata Oil Field where sedimentary rocks have been deposited since upper Miocene. Echigo Mountain Range is, however, composed of granite and other plutonic rocks, and of sedimentry rocks of Palaeozoic and Lower Miocene. Muikamachi Basin lies between the two geomoephologically and geologically different regions the older Echigo Mountain Range to the east and the younger folded region to the west.
The geomorphic development of the area studied has been interpreted by the auther as follows:
Uonuma Hills and Tôkamachi Basin were not yet differentiated in the first half of the Uonuma Stage, or Plio-Pleietocene_??_Pleistocene, when Echigo Mountain Range supplied deposits to form an extensive depositional plain where Uonuma Hills and Tôkamachi Basin now exist. Then followed elevation of Uonuma Hills, resulting in the formation of Muikamachi and Tôkamachi Basins. This is indicated by the deposits of the latter half of the Uonuma Stage.
After the Uonuma Stage, Uonuma Hills and Tôkamachi Basin kept upheaving from the base level. During the upheaval, there wes a rather inactive stage of crustal movement, when two levels of terraces which were more extensive than others wens made successively. With no such stages of inactive crustal movements since then, the River Shinano and its tributaries have trenched the basin making several terraces of lesser extent. The folding which formed the synclinal Tôkamachi Basin and the anticlinal Uonuma Hills continued to take place during the upheaval and it deformed some terrace surfaces. Muikamachi Basin has remained as a depositional basin after the Uonuma Stage and there few terraces are found.

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The author treated first the changes of river bed in the lower stream (0_??_32km.) of the Ôi River in Shizuoka Pref. by considering a) fluctuations in the mean heights of river bed and b) quantities of deposition or scouring in river bed. Then he dealt with the relation between the changes of river bed and gravel mining in the same stretch.
The mean heights of river bed and cross sectional areas of 116 gauge stations were measured and recorded by the Chûbu Branch Office of the Ministry of Construction. Seven measurements were carried out during past 9 years (1955_??_1963).
Conclusions are summarized as follows:
(1) When the mean heights of river bed (divided into 23 sections at intervals of 1 km.) in 1963 are compared with those in 1955, it can be recognized that the former has been considerably lowered in contrast with the latter overall sections. The average degradation for all sections is 33.6 cm., although values of over 70cm. have occurred locally.
Fig 2 shows the fluctuations in the mean heights of river bed during the period 1955_??_1963 in 11 sections and Fig, 3 shows the fluctuations in the longitudinal profile regarding the mean heights of river bed in 1955 as a standard.
(2) The yearly records of the amount of deposition and scouring in river bed show a huge amount of scouring for every year since 1958 excepting 1958 and 1961, the total amount of deposition and scouring recent 6 years (1958_??_1963) reaches about 3.7×10⁶m³ of scouring. Fig. 4 shows yearly fluctuations of the amount of deposition or scouring in river bed during these 6 years.
(3) The gravel mining in the lower stream of the Ôi River suddenly increased in the recent period. The total quantity of gravel mining during the 6 years (1958_??_1963) was estimated to be about 6.4×10⁶m³, which was twice the quantity allowed by prefectural government.
(4) Regarding the causes of the degradation of river bed, it can be considered that the effect of grvel mining in river bed is far direct and decisive as compared with other causes. Based on the analysis of data from 1955 to 1963, the author pointed out that there was a considerable correlation between quantities of scouring in river bed and quantities of mined gravels in the reaches of 0_??_18km., excepting a few sections (Fig. 5A). Moreover, there is also a considerable corrlation in the same reaches between the lowering of river bed calculated from the quantity of mined gravels and the degradation based on the actual measurement (Fig. 5B).
(5) It is to be seen, therefore, that gravel mining has been excessively undertaken in recent years, and yet, the scale of mining is still expanding. It this trend in mining is not reversed in the immediate future, the gravel mining in the lower stream of the Ôi River will be completely forbidden within ten years, for the possible amount of gravel reserves at the end of the 1963 fiscal year is estimated to be about 8.5×10⁶m³.

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As a result of various investigations, it has been found that Niijima Island in the Izu Archipelago consists of several volcanic masses which are mainly composed of liparitic lavas and ejecta erupted in the Quaternary.
The present writer newly defined the relationship between these lavas and ejecta in the formation of several Homa-Tholoides. We find three of them now existing at Mt. Miyatsuka, Mt. Atchi and Mt. Mukai. Almost all of the Homate of Mt. Miyatsuka have been eroded and destroyed, but both Mt. Atchi and Mt. Mukai still retain their Homates well preserved. (See Fig. 3 and Fig. 6)
A deposit of basaltic lapilli in the northernmost part of the island makes a sea cliff about 50 m above sea level. I. Friedlender considered that the lappili had been ejected from Udone Island (about 4km off the northern point of Niijima Island) which consists of basaltic lava and lapilli or scoria.
On the other hand, Tarô Tsujimura and Hiromichi Tsuya thought that the lapilli had come from “a craterlike hollow” which was inside the island (craters 1 and 2 in Fig .3). But the present writer believes that it was ejected from Craters 3 and 6 in Fig. 3 on the basis of its depositional feature. That means Craters 1, 2, 4, and 5 are a group of small Homates relating to Mt. Atchi.
It has also been discussed whether these ejecta-beds, both basaltic and liparitic, are of submarine or subaerial formation……the former was asserted by Nobuyo Fukuchi and Hisashi Satô, but the latter by Tsujimura and Tsuya.
The present writer concludes that these ejecta-beds are of subaerial formation because of new findings that the Mt. Daisan Tuff Breccia, lying immediately below the Shiromama (one of the most widespread deposits of liparitic ash and pumice) shows some features of fluvial erosion not retainable in the sea, and just below the sea cliff of the basaltic lapilli at Kadobara there can be seen a small exposure of a talus composed of liparitic materials. (_??_, _??_, in Fig. 4)
The above, coupled with the fact that all of these ejecta have been originated from Niijima itself, and that there are, in these ejecta, so many Tertiary materials ground in the sea…… (which are thought as fragments from the base of Niijima Island)……may possibly mean that some depression of the island happened after the last eruption, and, at least, that may confirm a common view of volcanology that we seldom experience the uplift after the eruption.
Reference: Hiromichi Tsuya's report in the Bulletin of the Earthquake Research Institute University of Tokyo, Vol. 15, published in 1937 in English, pp. 309-316 “On the Volcanism of Huzi Volcanic Zone, with Special Reference to the Geology and Petrology of Idu and Southern Islands.”

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