The buried topographies and paleo-environments were investigated in and around the Kuromegawa valley plain facing to the Arakawa lowland, in the central part of the Kanto Plain. Stratigraphic examination shows that two river terrace surfaces had been constructed before 20, 000-30, 000y. B. P., in the lower drainage of the Kuromegawa river incising into the Musashino upland. Although the Arakawa lowland was deeply dissected at the later maximum stage of the Last Glacial Age, the Kuromegawa valley was not eroded to that level.
It is clear that the post-glacial Jomon transgression invaded these areas and subsequently filled them with younger deposits, based on ¹⁴C datings and vertical changes of fossil diatom assemblages. The sea-level reached to its maximum height about 7, 000y. B. P. In the early stage of the transgression, fresh water sediments were deposited mainly in the lowland. As the sea-level continued to arose, an inner bay was formed extending about 1.7-2.0km into the valley at the maximum stage. Because the Arakawa river could transport larger amount of materials, natural levees and/or delta developed over the marine deposits at the mouth of the valley. However, it does not seem like that the valley was dammed by these fluvial deposits and a deep lake was created. The inner valley bottom had been dominated by maddy tidal flat. The marine regression resulted in marsh deposits resting on these sediments at most places.

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The age of accumulation of the Onikobe lacustrine sediments, and the ages of formations of fluvial terraces and alluvial fans in the Onikobe Basin, were estimated using field investigations and radiocarbon datings carried out by the present author. The results are summarized as followings.
1. The first wood sample collected from the Onikobe lacustrine sediments was radiocarbon dated to be 27, 100±2, 270 1, 745y. B. P. (TH-032). But ten further materials collected later from the Onikobe lacustrine sediments were older than 30, 740-35, 810y. B. P.. Judging from this evidence, the Onikobe lacustrine sediments began accumulating before 35, 810y. B. P..
2. In the Onikobe Basin, fluvial terraces have developed at four levels along the Araogawa river. Based on the radiocarbon dates of materials collected from some terrace deposits, the third river terrace surface, named Hara surface, was formed during 1, 100-1, 400y. B. P., while the lowest Kuze surface was formed about 800y. B. P.
3. In the southern and the western parts of the Onikobe Basin, many dissected valleys have formed on the alluvial fans. In order to estimate formative ages of the alluvial fans, a black humic soil sample was collected from one of the bottom of such dissected shallow valleys. The materials were radiocarbon dated, and showed 5, 170±90y. B. P. (NU-086). The age indicates that the alluvial fans were formed earlier than 5, 200y. B. P..

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The authors interested in the selective occurrence of the earth hummocks along the former river channels of the flood plain near the junction of the Harh river (_??__??__??__??__??__??_-_??__??__??_) and the Onon river (_??__??__??__??_-_??__??__??_), northeast Mongolia.
Some hand-bore tests and the small trench excavations had revealed the coincidence between the occurrence of frost involution and the belted existence of the clayey fine sand layer along the former river course, which might controlled the beginning of the earth hummmock formation. The earth hummocks are not found on the natural levee surface of gravels. The micro-relief formed by frost action may not be a fossil one but a current. The center of former Bindel-Som (village) had moved from the flood plain to the present site on the hill-foot gravelly surface some decades ago, as we heard, to avoid the frost heaving.

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Many landslides have developed at the end of low relief surface consisting of soft clay deposit (Late Pleistocene) in Onikobe basin, northwestern area of Miyagi Prefecture. In this paper the authors report microlandforms, landform process, occurrence condition and age, and indicate one of the landslide types, such as multiple slump.
The results are summarized as follows.
1) Landslide in northwest of Kitataki consists of microlandform units such as main scarp, some blocks (Kimata and Miyagi 1985) and secondary scarps. It is clarified that blocks have been formed by slumping and this landslide is multiple rotational slips (Hutchinson 1968) or multiple slump (Hatano et. al. 1974) type.
2) The ¹⁴C age of wood which was obtained from landslide deposit of Kitataki is 3, 130±240y. B. P.. And some lower terrace surfaces in this area which have emerged in 1, 400-500y. B. P. (Omoto 1992) are overlain by landslide deposits. It appears from the above that landslides in and around Kitataki have been mainly active since middle Holocene, 4, 000-3, 000y. B. P. and have continued.
3) Soft clay deposits in this area are high moisture content and slope of this clay was expected to be unstable once lateral support had been lost resulting from downward erosion.

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With the increment of transport demands, new construction and improvement of roads are being progressed. At the same time, traffics have been increased in periods of the rapid economic growth since 1962 in Korea. With the increment of automobiles, regional connection by the flow of automobiles is recognized as important research theme. Inter-city bus service as public transportation is the important means of passenger transport to serve for short and middle distance in Korea.
As regional characteristics are clarified by passenger transport business of inter-city bus, it is very important for us to explain the regional structure by the progression of transport industry.
Through this study, I attempt to clarify spatial patterns of the development of service network and competition among inter-city bus firms in Chungchong buk-do.
I used the data of Inter-city Bus Service published by the Ministry of Transportation and the data of the Lists of membership published by the Association of National Bus Transportation Business in 1990. The number of firm in this study is 6 in Chungchong buk-do and 32 in other provinces.
The analysis runs as follows: (1) Bus service network of inter-city bus was analysed to classify intra-province service and inter-province service. (2) The comparison with an inter-city bus and a cross-country bus of Chungchong buk-do and those of the others was analysed to understand the competition of route networks.
The results are as follows:
1. Route networks of intra-province bus service are concentrately established between Chongju (the largest city and the seat of provincial government in Chungchong buk-do) and Chongju (secondary city). Service network between Poun and Okchon county, between Poun and Youngdong county is established by intra-county bus in southern Chungchong buk-do, because service route network by inter-city bus is nearly not established in southern Chungchong buk-do.
2. Service network by inter-city bus between Chungchong buk-do and other provinces largely means that the extension of intra-province route to major city and town of contiguous provinces. And the extension of service route toward Chungchong buk-do by the bus firms of other provinces is based on the alienation among firms. And each firm has the vested rights with the relationship to service route in the time acquisition of permission and license in given route.
3. In Chungchong buk-do, the competition among buk firms between Chongju and Chungju is embarked by bus firms in Chungchong buk-do. And in southern Chungchong buk-do, the competition of bus routes appeared between bus firms of Chungchong nam-do (southern province) and Chungchong buk-do, and in northern Chungchong buk-do, the competition of bus routes appeared among Kyunggi do, Kyungsang buk-do and Chungchong buk-do. These phenomena are based on following reasons i) the geographical site of Chungchong buk-do, ii) route extension of cross-country bus firm of Kyunggi do which has many passengers demand, iii) neighboring Taejeon, and iv) decreasing population in Chungchong buk-do.

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