The results of a near shore survey conducted along the Ninomiya Coast during four periods in 1962, clarified the following facts regarding sediment circulation between inshore and offshore areas.
(1) Submarine Erosion
Submarine erosion during the summer is dependent on long wave action. Submarine erosion takes place only in restricted areas such as the seaward extension of giant cusps by convergence of wave energy by wave refraction. Such areas had been filled with fine sediments and are slightly elevated. Bottom currents transport fine sediments (less than 2φ median diameter) more readily than coarse materials (greater than 2φ median diameter). Fine sand particles behave similarly to medium and coarse sand particles in the threshold mean flow velocity, but the settling velocity is smaller for fine sand particles. Because the fine particles have been transported, only the coarse materials remain.
(2) Long Shore Current
Long shore currents with velocities of 40 cm/sec flow both eastward and westward along the Ninomiya Coast. The course of flow was near the shoreline near giant cusps and a considerable distance from the shore near bays. Such a meandering course illustrates the existence of normal onshore and rip currents as well as currents parallel to the shore. The normal currents transport suspended materials both onshore and offshore through giant cusps.
(3) Submarine Sedimentation
Due to turbulance caused by typhoons in late summer, sedimentation occurs in the near shore areas in contrast to the eroded beaches. Deposition of finer sediments (less than 2φ median diameter) takes place at the seaward extention of the giant cusps. The giant cusps tended to migrate and alter their form during the periods of survey. The deposits of fine sediments correspondingly migrated with the shifting of the giant cusps. Fine sediments that were deposited disappeared as inshore discharge of particles ceased. As beaches erode, submarine sedimentation takes place by means of rip currents in front of giant cusps.

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Northern part of Akita Prefecture, Northeast Japan, is the drainage basin of the Yoneshiro River, which rises from the Ôu Mountain Range and flows to the west to pour into Japan Sea, passing through Hanawa, Odate and Takanosu Basins and Noshiro Plain. At the northeast corner of its drainage basin, there is Towada Volcano whose double caldera is filled with water to form the Towada Lake.
Towada Volcano threw out pyroclastics several times at the last stage of the Quaternary period, and some of them went down as far as Japan Sea along the Yoneshiro River.
The author investigated the pyroclastic deposits distributed in the range from Hanawa Basin to Noshiro Plain and devided them into 8 members. They are (1)Nagadoro tuff, (2)Kosaka pumiceous ash, (3) Ogata lithic ash, (4)Takaichi pumiceous ash, (5)Torigoe pumiceous ash, (6)Sarugano pumiceous ash, (7)Ôyu A pumiceous lapilli, (8)Kemanai pumiceous ash from the older to the younger. Ôyu pumiceous lapilli is a pyroclastic fall deposit and others are pyroclastic low deposits. The last two (7, 8) are the deposits of the 2nd stage of Towada Volcano (the stage of a central cone in the older Towada Caldera) and others are ones of the 1st stage (the stage of a large strato volcano before the formation of Towada Caldera) or other volcano older than Towada Volcano.
Some terraces developing along the Yoneshiro River have intimate relations with the pyrcolastic deposits. For instance the depositional surfaces of Takaichi, Torigoe and Kemanai pumiceous ashes which are distributed more extensively than others can be recognized as terrace surfaces. Among them that of Torigoe pumiceous ash develops most extensively in Hanawa and Odate Basins. The depositional surface of Takaichi pumiceous ash is found only at the western part of Takanosu Basin and that of Kemanai pumiceous ash is distributed in the narrow belt along the Yoneshiro River in Odate and Takanosu Basins, Some interesting phenomena are recognized in the states of distributions of these pyroclastic flow deposits.
The height of the depositional surface of Torigoe pumiceous ash is lower at the central part than at the marginal part of the basins, and relative height from alluvial plain is almost constant. Accordingly it is said that the height of the depositional surface does not always become lower with the distance from the crater, but is influenced strongly by the existing land forms.
In Takanosu Basin, Takaichi and Torigoe pumiceous ashes cover the existing terraces of fluvial origin with almost equal thickness (less than 1.5 m), as if they were pyroclastic fall deposits. This phenomenon leads to the idea that the flowing cloud of pyroclastics covered the basin as far as a certain height and left thin deposits upon the terraces.
The relative height of the depositional surface of Kemanai pumiceous ash and the floor of the Yoneshiro River is 15 m at the gorge between Odate and Takanosu Basins, and about 8 m in both basins. It is presumed, therefore, that at this gorge Kemanai pyroclastic flow was obstructed to flow smoothly and left thicker deposits than in both basins.

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The land-value of streets is a useful criterion for the purpose of studying the locality of Central Business Districts (CBDs), as the core of the economic activities in the city region. Combining the area and the difference between the highest and the lowest land-value of CBDs, the types of CBDs are established according to the pattern, area and function of each CBDs:
(1) When the CBDs of the city region are situated further from main railway stations, the differences between the highest and the lowest land-value of CBDs diminish generally at a higher rate than the diminishing rate of the area of CBDs.
(2) Generally, the rank of CBDs is proportional to the city population, except for some industrial cities without prefectural governments : eg. Kawasaki, Hamamatsu, Himeji, and a city with geographical difficulty for its activities : eg. Kanazawa.
Obeserved from the distribution of CBDs, cities belonging to the lowest rank of CBDs dD type are distributed mainly in the Tohoku District and southern Kyushu District, while cities belonging to the higher rank of CBDs aA, aB and bA types are distributed in the Tokai District, Setouchi District and northern Kyushu District.
(3) “aA” type denotes the most extensive area and a noticeable difference between the highest and the lowest land-value of CBDs, and the CBDs of “aA” type consist of the streets with various functions, the maximum land-values being the business streets.
“dD” type denotes the smallest area and the lowest difference, and the CBDs of “dD” type are organized with the least and lowest functions, with shopping streets having the maximum land-values.
Each type between the largest “aA” and the smallest “dD” type is decided according to the relations between two elements—the area of CBDs and the difference between the highest and the lowest land-value of the established CBDs.

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The results of the investigation on the Ghanads or Qanats in the Qazvin Basin, locating in the northern part of Iran at the elevation of 1, 100 m to 1, 350 m, are summarized as follows :
The Qazvin Basin is surrounded by Elburz Mts., consisting of Palaeozoic, Mesozoic and Tertiary formations in the northern part, and mountains and hills, consisting of Igneous rocks and Tertiary formations in the western and southern parts, and is filled up with thick flood plain deposits. It has a triangular shape, at the northern apex of which the city of Qazvin is situated, and is roughly divided into two geo-morphological units ; fans and flood plains.
The land neighouring the city of Qazvin with approximately 1/200 gradient is characterized by the densely developed Ghanads (Fig. 2), average length of them is less than 3 km, and the longest one reaches 8.8 km. The most of them streches 1-3 km, as seen in Fig. 3. The amount of water from a Ghanad was 0.2-0.6 1/sec, when measured in November with less precipitation.
The amount of water of the Ghanads is decreasing year by year, due to the depression of ground water table. It is said that there is left no possibility of developing the Ghanads in future. Instead of the Ghanads, the developments of deep wells to pump up water by motors is now rapidly progressing at many places in the Qazvin Basin. Such development combined with water reservoirs by dam system will be recommendable for such arid regions in future.

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