The Ishikari plain is a typical coastal plain which is divided into major four geomorphic units (Ishikari beach, Ishikari sand dunes, Bannaguro sand bars and Momijiyama sand dunes) (Fig. 1). The purpose of this investigation is to clarify the difference of four geomorphic units in term of depositional environments and to distinguish grain-size distributions of sandy deposits in the different localities of the same type geomorphic unit.
In order to know the grain-size distribution and its relation to depositional environments, the author analyzed 66 samples using grain-size parameters and Q-mode factor analysis. The results are summarized as follows:
1. As for the mean-size of sediments, there are no distinct differences in the other three geomorphic units, except sands of the present beach having the largest value among them (Tables 1 and 2). Sands of the Momijiyama sand dunes are more poorly sorted than those of the other three environments. This fact means that sand deposits are getting to be more poorly sorted inlandwards in the Ishikari plain (Tables 1 and 2).
Although skewness and kurtosis usually indicate the difference of depositional environments, it is difficult to distinguish Ishikari sand dunes from Monijiyama's (Table 2).
Grain-size parameters merely show the trends of grain-size distributions and depositional environments. Thus, grain-size parameters are not useful to indicate the detailed characteristics of the geomorphology and the division of depositional environments.
2. Appling a Q-mode factor analysis, three basic kinds of energy which are responsible for the deposition of sediments are postulated (High-energy: Factor I, Medium-energy : Factor II, Low-energy: Factor III) (Fig. 5). These three eigenvalues account for 98% of total variability (Table 3).
In the Ishikari plain Factor II type sediments occur in the noutheastern part, while Factor III type sediments occur in the southwestern part (Figs. 4 and 5). The area of the strong westerly winds estimated by the wind-shaped trees and the wind data obtained at the meteorological stations correspond with the regional distributions of depositional environments estimated from the types of energy (Fig. 5).
This relationship implies that depositional environments at a given locality in the Ishikari coastal plain are deeply influenced by the strong westerly winds and strong wave actions. Therefore, it can be concluded that the Shakotan and the Takashima peninsulas which are located to the west of the Ishikari coast play an important role on the Ishikari coast, because they block the strong westerly wind from the southern part of the Ishikari coast.

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This article attempts to describe the regional distribution of foreign employees in the Federal Republic of Germany (FRG), and to explain its dynamics in terms of the social, political, and economic processes involved.
There are only a few works that have dealed with the dynamics of the regional pattern of foreign employees, such as Hottes and Meyer (1977), Giese (1978), and Leib and Mertins (1980). But each paper has its own shortcomings in some respects. The diffusion processes of Italian, Greek Spanish, Portuguese, Yugoslav, and Turkish workers that Hottes and Meyer (1977) describe are unreliable because of lack of evidences in the 1960 s.
Although Giese (1978) adopts a viewpoint of spatial diffusion, too, and analyzes it in more detail than Hottes and Meyer (1977), his basic assumptions are irrelevant. He insists that the information concerning foreign workers diffused from Swiss employees to German partners, and further from the Stuttgart Metropolitan Area to the northern part of the FRG. We must, however, comprehend that there was scarcely time lag of the information flow, because the German government, namely the Federal Labor Office (die Bundesanstalt für Arbeit), its local branches or the Employment Exchanges (die Arbeitsämter), and its abroad branches in this case, plays the most important role of recruiting foreign workers. Moreover it is also irrelevant that Giese (1978) underestimates an economic factor, because the variables in his non-linear multiple regression analysis do not represent the real economic situation.
Leib and Mertins (1980) criticize the Giese's conclusion, too. They analyze the dynamics of the regional distribution only of Spanish employees, and conclude that they have been pconcentrated in the Rhein-Main-Gebiet, the Hannover Metropolitan Area and so on since 1961 and that a diffusion process like a wave cannot be found out. They put this phenomenon down to the immigration of chain-process type. But their description concerning the recruiting route of foreign workers seems to be incorrect, so that they underestimate the Feconomic factor, too.
After such a critical review, the present author shows first of all in which district of Employment Exchange foreign employees have accumulated (Figs. 3 and 4). It is clear that a large number of foreign workers are employed principaly in the Rhein-Bergisch-Märkisches Land, the Rhein-Main-Gebiet, the Stuttgart Metropolitan Area and the München Metropolitan Area, followed by the south of Baden-Württemberg, the Nüurnberg Metropolitan Area, the Rhein-Neckar-Gebiet, the Hannover Metropolitan Area, the Hamburg Metropolitan Area, Berlin (West), and Saarbrücken. In spite of business fluctuations, this pattern has been maintained since 1965 at latest, while the rate of increase of foreign employees was higher in some metropolitan areas during the boom and Bielefeld, Bremen and so on have appeared later as accumulation region. Each national group displayed a similar pattern during the period of 1965_??_1979 (Figs. 5_??_14), although it seems that there are some particular relations between each national group and some regions. Such relations can be shown most clearly in the map of location quotient (Fig. 17). However the degrees of correlations between each pair of distribution patterns of Italians, Greeks, Spaniards, Yugoslavs, and Turks are very high (Table 1).
The above mentioned pattern results from the economic situation in each district of Employment Exchange and the recruitment system rather than the chain migration. There are four routes for recruiting foreign workers in the FRG. The first route is through the Federal.

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The Obitsu and the Yoro rivers are located in the central part of the Boso Peninsula. Meandsring valleys and many strath river terraces are developed well in the upper to middle courses of both rivers. On the basis of the topographic classification of those terracces by the aerial photo interpretation, the past developmental process of valley incision can be deduced from the distribution characters of those terraces. The past developmental process of the Alluvium deposition in the lower courses of both rivers can be reconstructed by the analysis of coring data and by the investigation about the continuity between the profiles of buried valley floor below the alluvial plain and those of river terraces.
The aim of this paper is to investigate the chronological relation between the developmental process of valley incision and that of the Alluvium deposition, and to discuss the effect of sea level change on the development of the river valley in the upper to middle courses.
The results obtained by this investigation on the geomorphic development of both rivers are summarized as follows.
1. In the upper to middle courses of both rivers, valley incision has continued at least since ca. 20, 000 Y. B. P., because no fill top terraces can be found along the courses. There are typical topographies which can be thought to be made by the past cuttings of meandering channels. Those cuttings had been formed frequently in the first half of the Holocene. This evidence shows that the lateral erosion of the river had been dominant over the down cutting in this period and the valley meander could have grown easily. In the latter half of the Holocene, however, the cutting of the meandering channel has hardly been made so that the deepning of the valley has been predominant, leaving the former meandering pattern.
2. In the lower course of each river, it is assumed that the sedimentation of the Alluvium had began at the end of the Pleistocene estimated from the radiometric datings of the lowest part of the Alluvium and the correlations between the profiles of burisd valley floors below the alluvial plain and those of river terraces. In the first half of the Holocene, the Alluvium had rapidly deposited with the rise of sea level, and the depositional area of the Alluvium had d the spred inland. The Alluvium deposition has been over about 6, 000_??_5, 000 y. B. P. an surface of the alluvial plain has gradually emergenced from the inland part of the plain. This retreast of the dePositional area of the Alluvium is thought to be caused by a little fall of sea level since ca. 6, 000_??_5 000 y. B. P..
3. The correlation of river terraces from the upper to lower courses shows that the change of the character of valley incision in the upper to middle course had begun at the same stage retreat of the depositional area of the Alluvium had started in the inland region of when the the plain. This phenomenon is considered to show that the change of base level of erosion, which have been caused by the sea level change since the Late Plesistocene, has effected on the process of valley incision in the upper to middle courses, because the pattern of crustal move ment in this area is thought to have hardly changed since the Late Pleistocene Juding from the distribution characters of the river terraces.

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Fluvial terraces are widely distributed along the lower stream of the Shinano River from Ojiya city to Nagaoka city, Niigata prefecture, northeast Japan. This area has experienced active crustal movement since the Tertiary period, and the deformations of terrace plains by active folds and faults are distinctly recognized. Therefore, this area is well known as one of the best fields in Japan for studies on active crustal movement, especially on active folds. Many works have been published about fluvial terraces and active crustal movement in this area since pioneer works by Ikebe (1942) and Otsuka (1942), but few detailed studies about formative age of fluvial terraces have been published except Ota (1969).
Tephrochronological approach is usually effective for regional geologic chronology. The purposes of this paper are to determine the formative age of fluvial terraces by means of tephrochronological approach, and to calculate the deformation rate of terrace plains. Main results are summarized as follows.
1. Three dated marker tephra layers were found out in this area. They are Aira-Tn ash (AT, ca. 21, 000 22_??_000 y. B. P.), Daisen Kurayoshi pumice (DKP, ca. 45, 000_??_47, 000 y. B. P.), and Nakago pumice layer (NG, ca. 130, 000_??_150, 000 y. B. P.).
2. Based on the stratigraphic relationships between terraces and these marker tephra layers, formative ages of fluvial terraces were determined as follows;
A Terrace (Koshijippara terrace): ca. 130, 000_??_150, 000 y. B. P., B Terrace (Kowadappara Terrace): ca. 50, 000_??_60, 000 y. B. P., C Terrace (Funaokayama Terrace): ca. 21, 000_??_25, 000 y. B. P., D_??_F Terraces: younger than 20, 000 y. B. P., perhaps Holocene.
3. The average rate of the northward tilting of the fluvial terraces in the region is recalculated as about 0.15_??_0.17mm/km•year during the past 130, 000_??_150, 000 years, and about 0.13_??_0.16mm/km•year during the past 50, 000_??_60, 000 years. Both values correspond well with the rate of the tilting deduced from the precise relevelings (0.19 or 0.15mm/km•year, Mizoue et at., 1980).
4. The average rates of the tilting at the west wing of the Ojiya syncline (Ikebe, 1940) during the past 130, 000_??_150, 000 years and 50, 000_??_60, 000 years are 0.4‰•1, 000 years and 0.4_??_0.5‰•1, 000 years, respectively.
5. The above-mentioned facts in 3 and 4 imply that the active folding in this area has proceeded at a nearly constant rate during at least the past 150, 000 years.
6. The Katakai faults (Ota, 1969) cutting A Terrace have displaced at the order of 0.01_??_0.1m/1, 000 years.

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