This is a report on the changes of the characteristics of the Muroran Port on the southern coast of Hokkaido.
The history of the development of this port can be divided into the following four periods. The first period is the age of this port as an entry of immigrants (1872-1898). The second period is the age as a shipping port of coal (1899-.). The third period is as the domestic liner port (1907-), and the fourth period is as an international port as an iron industrial port (1950-).
The total cargo of the port is 1881 million tons in 1964 ranking eleventh in Japan. The raw materials and products of the iron work (The Fuji Iron Manufacturing Co.) and some other plants associated with the iron work occupy 45% of the total cargo, and the coal for shipping is 30%.
The wharfs of the port consist of the private wharfs and the public wharfs, and 91% of the total cargo is handled at the private wharfs of the Fuji Iron Manufacturing Co. Compared with the development of the other industrial ports of Japan, the rapid modernization of Muroran Port is noticeable.

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In his last paper, the author described the distribution of farming households with part-time workers and its changes in the area around Sendai City. In this paper, he discusses the population structure of farming households with part-time workers in the same area.
There are some remarkable regional differences between the areas mainly with part-time farming households and those with full-time farming households, especially concerning age structure, school background and sex ratio of full-time farmers, and concerning the succession of farming. The situation of the supply of agricultural labour is much affected by the employment in areas of dominantly part-time farming. In the full-time farming areas, it is affected by the modernization of agriculture such as the introduction of agricultural machines.

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The writer found some Blockströme in the valley flat (altitude of 400-200 meters) at Shirayamadôyama (granodioritic) and Yagoshiyama (monzonitic) in the Kitakami Mountainland. In these areas Blockströme are 150-500 meters along and 10-60 wide with a depth of several meters, and gradients of these Blockströme are 5-10 degrees on an average. Blocks in Blockströme are 1-4 meters in diameter and have the shape of “Wollsack”, but a considerable part of these blocks has the sub-angular form in Yagoshiyama area.
In all Blockströme in these areas, the present movement is unrecognizable and the water at the bottom of a Blockstrom has a tendency to wash away interstitial earthy material. It seems that these blocks in Blockströme are not the core stones out of the deep-weathered bed rock in situ, but were transported by means of mass movement from the upper slopes and Felsburgen.
As to the development of Blockströme in these areas, three stages are recognized: the first stage is a period of extensive sub-surface rock weathering whose pattern is controlled by structural conditions: the second stage is a period of the exhumation of core stones and Felsburgen (by removal of the fine-grained products of rock decay) and the transport of blocks by means of mass movement: the thrid stage is a period in which interstitial earthy material was washed away.

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The Kesennuma Bay, which has two branch embayments To-wan (eastern bay) and Sei-wan (western bay), is in the southern part of the Sanriku Rias coast, which is considered to be a submerged marginal area of Kitakami Mountains. It is generally said that terraces develop poorly along the Rias coasts. Along the coast near the Kesennuma Bay, however, terraces and constituting deposits are distributed rather well. The results of the author's study on terraces and relating matters are as follows.
1) Coastal terraces are classified into Mitsumine Terrace, Shinjo Terrace, Matsuiwa Terace, Iwatsuki Terrace and Katahama Terrace from the upper to the lower.
2) The terrace deposits excepting that of Katahama Terrace consist of gravels which are maturely weathered into Kusari (decayed) Gravel, and silt and sand lenses. Matsuiwa Terrace and Iwatsuki Terrace are composed of fluvial deposits iii the lower part and marine in the upper beds. Uncomformity between the bedrock surfaces and terrace deposits indicates valley forms like a buried valley beneath the alluvial plains.
Red weathered crusts and soils are observed on the terraces higher than Katahama Terrace. From the above mentioned facts the author estimated that Matsuiwa Terrace and Iwatsuki Terrace were formed at least during the stages of high sea levels which followed the low sea level stages.
3) Katahama Terrace surface is about 6m high above sea level, and a few meters higher than coastal lowland surface.
4) Recent drowned valley is shown along the To-wan which is embranced by the Karakuwa Peninsular and the Kesennuma Oshima island (Fig. 6). The embayment of Ria shoreline at the Kesennuma Bay had been formed before these terraces were built. From the distribution of Senganda Formation it is considered that the formation of Ria shoreline at this area is dated back to Plio-Pleistocene.

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The Ichihazama and the Nihazama rivers originate in the back-bone range of Tohoku, run through hilly area of Pleistocene Pyroclastic-flow deposits, and reach the Snauma lowland in the northern part of the Sendai plain.
The results of the author's study on the river terraces and hills along these rivers arc as follows;
1) The geomorphological surfaces are classified as in Fig. 1, and the relation between terraces and the lacustrine deposits is shown in Figs. 8, 9 and 10.
2) The western part of the hills is composed of dacite and tuff of Pleistocene (Kitamura 1956) and the hilltops in the eastern part of it are covered comformably with gravel bed (Hanzawa, Kitamura 1957). Fujiwara (1958) suggested that the hill surface is subdivided into two levels covered with different gravel layers without detailed description and mapping.
The present author has acertained that the eastern part of the hills consists of the remnant surface of terraces in two levels: the upper one 70 to 90m, and the lower 40 to 50m above sea level. The upper covers comformably the pumiceous tuff in the lower half of the middle reaches as was reported by Hanzawa and Kitamura (1957) and others, while in the upper half the surface of pumiceous tuff is terraced and the older alluvium underlies a lower level terrace surface in dendritic pattern. The longitudinal pattern of the older alluvium is shown schematically in Fig. 7. The levels of deposition and erosion on these two, therefore, are about 70m and 50m above sea level.
3) The upper Tsukidate surface is distributed widely in the middle reaches. The surface was reported hitherto as that of fluvial origin, however it is fill terrace formed at the time of the high sea level at the hieght less than 20m above sea level. Fujiwara (1958) suggested an uplift of the surface near Tsukidate by means of drainage pattern analysis. The author presumes that the terrace-building was influenced by a regression of sea, and in the development there may have been a tectonic movement.
4) Oide (1964) reported that certain deposits upvalley a gorge in the upper reaches of the Ichihazama river is lacustrine deposits lain in a lake basin produced by an uplfit of gorges of Miocene andesite. In his opinion the barrier is shown with the site of present gorges. Imaizumi (1966) supported his opinion. The present author thinks that the lacustrine deposits was lain through violent accumulation of voluminous sandy tuff in a short time, for the deposit scarcely shows lamination and has nodules, erected stumps and pisolite particles in non-stratified material. The heavy-mineral analysis reveals that the lacustrine deposits are same as the Kitagawa formation (dacite and its tuff) and the uppermost volcanic ash on the terrace and hill surfaces along the Eai river.
5) The gentle slopes of erosion cut terraces under-lain with so-called lacustrine deposits in the upper reaches of the Ichihazama river. Some of their lower flanks may have been buried beneath the alluvial plain surface in the middle reaches. Drift wood in the so-called lacustrine deposits was dated 27, 000±1, 700yrs B. P. by C-14 method (Oide 1964). Its form is very much akin to cryopediment (Wako 1960).

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The population of Sapporo City increased from 601, 151 to 795, 901 in the period of 1960-1965. The aereal differences of population change in this period shown in Fig. 1 reveals the population decrease in the central part, a high rate of increase in the outskirts and a low rate of increase in the middle zone. Fig. 2 shows the relationship between population change and its density. From these maps, a close relationship between these two elements are known.

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There is a series of distinct breaks of hillslopes at the height of 30-70m in the hills situated at the north and west suburbs of Sendai City, which consist of flattopped erosion surfaces (150-100m) cutting Pliocene sandstone and shale. Above these breaks develop the foregoing landforms, e. g. high level valleys, concave slopes, and erosion surfaces; below the breaks, on the other hand, predominate present landforms, e. g. V-shaped valleys, Sohlen-kerbtal, and valley plains. Separated by the breaks these two kinds of forms co-exist in the hills discontinuously adjacent to each other.
The breaks bring the slopes to have a two-cyclic form on their profiles, and indicate a front line of the area of fluvial erosion encroaching into the area of surface denudation. The breaks are favorably preserved in the hills near the main divide, due to a kind of locational conditions.

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Some terrace deposits have been found in Sendai Bay area in an occasion of a road cutting after the report by T. Wako (1964). Generally these are composed of gravels of andesite, gravels and water-worn breccia of tuffaceous siltstone and sandstone; from facies of deposits these are believed to be of marine origin. It is of great worth that the bases of terrace deposits are found in 95m, 90m, 55m, and 2m above sea level respectively. The plane of unconformity 2m high from sea level serves for the subdivision of so-called coastal lowland, and the upper ones guide the way of the study of hill land formation along Sendai Bay.

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In 1953, the author observed clear eye-blow fault scarps cutting new compound fans at the north-eastern foot of Mt. Koshiba in the southern margin of the Onikobe Basin, Miyagi Prefecture. The fault scarp runs about 1km from WNW to ESE and the maximum relative height of the scarp is 10m. Other parallel scarps are seen at the western end of that.
There are older fans at the upper part of new fans. The margins of the old fans are seemingly originated from old eye-blow fault scarps, because the end scarps of old fans are linear and are parallel to the former eye-blow fault scarps.

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