By “shima-batake” landscape is meant landscape in which upland fields of various shapes, approximately 50-80 cm. above the ground of paddy-fields, are distributed among paddy-Melds, much as micro-buttes are scattered over a plain, or numerous small flat islands are scattered over the sea. In regions where “shima-batake” are densely distributed, there are cases in which the area of upland fields is larger than that of paddy-fields. The purpose of the present paper is to clarify in which regions such landscapes are found. In the first place, after making a detailed inquiry into the relationship between the distribution of “shima-batake” and micro-land forms as well as irrigation in the Hamana and Iwata Plains in the downstream region of the Tenryu River, consideration was given to the origin of “shima-batake.” By a similar method of investigation, inquiry was made into the downstream plains of the Kiso River, the Yahagi River, the Toyo River, the Sagami River, the Kuji River, the Naka River, the Shinano River, the Agano River, the Kariyata River, etc., and also the coastal plains of the Tone River, the Kinu River, and the Naka River, as well as the downstream plains of the Yoro River, the Obitsu River, and the Koito River, on the west coast of the Boso Peninsula, the Kujukuri coastal plain, and two other regions.
Approximately 40 years ago, Prof. Glenn T. Trewartha expressed his opinion concerning the “shima-batake” in the downstream plain of the Tenryu River (Annals of American Geographers, Vol. 18, 1928, pp. 127-257). In a recent work, he has expressed the same opinion as before (Japan, a Geography, 1965, p. 652). His opinion is as follows: As a result of the flooding of the Tenryu River, large deposits of detritus were made in the paddy-fields, and the irrigation canals were buried. In their work of restoration following the disaster, the farmers removed the detritus from the paddy-fields and irrigation canals, and piled it up in one part of the paddy-fields, which they later leveled out to make upland fields. These up-land fields formed the “shima-batake.” The present writer, however, cannot agree with this opinion in view of the fact that “shima-batake” are distributed even in diluvial tablelands that are entirely free from any danger of flooding, as well as for other reasons.
The present writer holds the following view: In regions where “shima-batake” are distributed, the slope of the land surface is extremely gentle, and the surface abounds in micro-relief. (In general, the difference in height between the high parts and the low parts is less than about 80cm.) Again, the water-level of the irrigation canals in such regions is approximately the same as the height of the lowest part. Moreover, the source of irrigation water is far from abundant. In such a region, in the days before pumps could be used, the farmers had no choice but to level down the high parts and make paddy-fields in order to expand their paddy-fields. The present writer thinks that it was as a result of the expansion of paddy-fields in these regions by individual farmers that the complex distribution pattern of paddy-fields and upland fields was formed.
Recently, in regions where plentiful irrigation water has been made available by the use of pumps, “shima-batake” have been leveled out, and the whole region has been made into paddy-fields. Again, in regions where the area of paddy-fields cannot be expanded because of the limitation of irrigation water, and in other places where it was felt desirable that the upland fields should be left as they were, numerous small “shima-batake” have been combined to form upland fields with large areas.

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Mt. Fuji and Mt. Hakone volcanoes lie in the south-west of the Kanto plain and supplied a vast amount of tephras (pyroclastic-fall deposits) through late Quaternary times. The tephras deposited are thicker near the volcanoes and are considered as useful key beds for analysing the history of the volcanoes and the development of terraces.
The present paper is devoted primarily to a study of the history of the volcanic activities of Mt. Fuji and Mt. Hakone from the tephrochronological study in the Ooiso hills, where abundant tephra layers and Quaternary sediments are found.
In the first place, the most important key bed, “Tokyo pumice”, about which we have as yet very little information in the studied area, has been discovered as a conspicuous pumice bed accompanied with the younger pumice flow deposit of Mt. Hakone volcano. As the Tokyo pumice is a useful horizon marker of the lower Musashino loam formation, the younger pumice flow deposit is placed stratlgraphlcally in this horizon, which is different from those which were reported before.
In the next place, the Pleistocene tephra layers in the Ooiso hills are divided into three formations ; the Younger loam, the Kissawa loam and the Tsuchizawa loam. These results are obtained from the relation between tephras and geomorphic surfaces.
An idealized geological section of the north-east of the Ooiso hills is shown in Fig. 7.
The Kissawa loam, the Kissawa formation and the Kissawa surface are the new geological names. The latter two may have been formed under a remarkable transgression prior to the Holocene epoch, which can be correlated to the Sangamon interglacial.
Fig. 8 shows the relationship between the thickness of a tephra and the geological age. The former is expressed by relative figures measured at a certain distance from the crater along the axis of distribution, because this is considered to represent the total volume of a fall unit which is in turn a function of explosivity of an eruption.
The tephras of the two volcanoes are interbedded each other., but can be distinguished from the petrological point of view; those of Mt. Hakone are pumiceous deposits of two pyroxene andesitic compositions, and those of Mt. Fuji are scoriaceous of olivine basalt.
As shown in this figure, the following results are to be found.
1) The activity of Mt. Fuji started later than that of Mt. Hakone.
2) Mt. Fuji successively erupted through the time of late Pleistocene until about the beginning of the Holocene. This period of activity was called the “Older Fuji I” as compared with the period of the “Older Fuji II”, the effluent time producing lava flows, and with the “Younger Fuji” of middle to late Holocene (Machida, 1967).
3) The activity of Mt. Hakone volcano continued for a long time gradually decreasing in explosivity. From the precise interpretation, the several periods of activity are recognized; I, II (the Older Somma stage I and II), III (the Younger Somma stage) and IV (the Younger Pumice flow and the Central Cone stages accompanying the caldera depression in the younger stage). Those results are obtained from the correlation between the stratigraphy of tephra and the development of the volcanic edifice.
And then it is clear that the three greatest explosions occurred after each long quiescent period of activity shown by the Tsuchizawa pumice, the Kissawa A-pumice and the Tokyo pumice. The volcanic activity became less explosive as well as less frequent in the IV stage, while several central cones were constructed.

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Two rainy periods might be identified in this country, occurring before and after fairly dry summer season. The former one is the Bai-u season which persists from the beginning of June to the middle of July and prevails mostly in southwestern parts of the country. And the latter one is the autumnal rainy period which starts from the end of August and lasts to the middle of October. In northern Japan, this rainy period is more remarkable than the Bai-u season and records heavier rainfall. It is generally believed that autumn is the fine and refreshing season in this country, but statistically as is shown on Fig. 1, early autumn is an obvious rainy period.
[1] Climatological Aspects.
The geographical distribution of total amounts of rainfall in September and October (1931-60) is demonstrated on Fig. 2. On this map, the following distribution characteristics might be pointed out:
1) Heavy rainfalls of more than 400mm have been reported along the coastal regions of the Pacific and also Japan Sea sides. At certain stations along the Pacific, they have measured heavier rainfall than 600mm for the total of these two months.
2) Along the central axis of the Japanese Islands, there has been a prolongation of fairly dry belt having less rainfall than 300mm.
3) Hokkaido, the northern island, is a rainless area in the country and reports only about 200-300mm of rainfall.
Fig. 3 illustrates geographical distribution of the ratios of September and October rains against annual amounts. This ratio might serve as an index of the degree of concentration of autumnal rains. Almost all stations, except the southern island, Kyushu, have registered higher ratios than 61/365 (supposed even occurring probability). Then, they suggest that the rainfall concentrations in September and October at various places are high and these two months may be regarded as the autumnal rainy period.
The geographical distribution of the ratio of the autumnal (September & October) rains against the Bai-u (June & July) rains is indicated on Fig. 4. The areas which the autumnal rains predominate more than the Bai-u rains are figured out along the coastal regions and in the northern parts of the country. And the Bai-u areas are distributed mainly in Kyushu and along the central axis of the Japanese Islands.
September and October in this country is also the period of typhoons. Therefore, the amounts of rainfall of these two months definitely include typhoon rains, besides of non-typhoonal rains. On this paper, it has been devoted to analyse principal characteristics of such non-typhoonal rains. Thus, typhoon rains and non-typhoon rains have been separated on these two months, based on synoptic analysis. Their amounts and ratios against total rainfall have been tabulated on Tab. 1, at 16 selected weather stations representing various climatic regions in the country. Typhoon rains reach 30-50% of total amounts for this season at almost all stations. The distribution of typhoon rains in September and October during the periods of 1956-60 have been demonstrated on Fig. 5.
Along the Pacific coasts and in the southern Japan, it has been observed heavy typhoon rains of more than 150mm. And this distribution pattern suggests complex distribution characteristics of the orographic band-structure and the coastal-rain type. These two are typical distribution patterns of daily typhoon rains.
Non-typhoonal rains which occupy 50-70% of total amounts of September and October rains are mainly caused by cyclones and frontsmeteorologically. Their occurring frequencies are tabulated on Tab. 2 and the geographical distribution of total amounts of the non-typhoonal rains is illustrated on Fig. 7.
The most remarkable characteristic of the distribution is few regional diversities. Almost every station has reported about the same amounts of rainfall around 200-300mm.

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