The author tired to restore the geomorphic development of alluvial coastal plains, related to the Holocene sea-level change. The Holocene shoreline had advanced seaward during the progressing period of coastal plain, since about 6, 500-7, 500yBP to the present (Matsumoto 1981a, 1981b).
This paper examined the difference of the size frequency distribution between aeolian and marine sand deposits in coastal areas, to estimate the changing altitude of the former shoreline based on the grain size analysis. The samples were collected from some coastal areas in northeastern part of Honshu Island, i. e. Sendai, Ishinomaki, Akita and Shoai coastal areas (Fig. 1). Each coastal area has a long sandy bach. The sampling sites are shown in Figs. 3, 6, 8 and 10.
The aeolian sands were sampled from modern sand dunes and the marine sands were sampled from swash zone and shollow marine (see Fig. 2). In the laboratory, grain size determinations were made on these smaples by conventional sieving methods, using 1/2φ sive intervals. The difference of size frequency distribution was examined in each locality. The results are shown in Figs. 4, 5, 7, 9 and 11. Aeolian sands are clearly distinguished from marine sands on each coastal area. For example, at Sendai and Ishinomaki coastal areas, the two kinds of sands are separated by the value of skewness, and at Akita and Sonai coastal areas the two kinds of sands have no difference in skewness, but they have difference in standard deviation. Statistical parameters such as mean, standard deviation and skewness of the two kinds of sands have particular boundary values in each coastal area. Then the differentiation between aeolian and marine sands should be recognized under the unique rule on each coastal area.

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Relative changes of sea-level during late-Holocene time were restored in Tanabe Bay, the southwestern part of the Kii Peninsula, though geomorphological-stratigraphical analysis of erosional features such as wave-cut benches, notches and caves, and depositional ones such as raised sand bars and delta surfaces, which are developed on several levels and partially occupied by prehistoric sites of respective ages.
Immediately after the highest sea-level phase which is indicated by the 6.0-6.5m benches on rocky coast, Sand bar I was developed in the middle Jomon period (around 4, 300yrs. B. P.) in the mouth of drowned river valleys at the innermost part of the bay. It was followed by the 3.5-4.0m sea-level phase indicated by the higher benches, notches and caves. The middle benches and notches. Sand bar II, and wide beaches which are developed even on rocky coast indicate the next phase of stable sea-level at 2.0-2.5m above the present level which seems to have been preceded by a regression attending to a little lower than 2m above the present. It is estimated to be around 2, 400yrs. B. P. The following rapid regression in the Yayoi period provided the sea-level lower than 2m below the present, as suggested by the facts that Sand bar I, Sand bar II and the upper delta are dissected by shallow troughs and the lower delta was formed.

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This study attempts to clarify the detailed wind system of the Nasu-oroshi in the northwestern part of the Nasu alluvial fan as revealed by wind-shaped trees and windbreaks. In addition, to clarify the characteristics of the Nasu-Oroshi, field observations were made by using meterological instruments.
The results obtained can be summarized as follows.
1) By means of prevailing wind distribution as revealed by wind-shaped trees and windbreaks, strong westerly winds were discovered along the Sabi and Hohki rivers. The revealed winds are particularly strong at the head of the alluvial fan, from where they spread out following the pattern of the alluvial fan.
2) When the strong westerly winds blow, the air temperature decreases, as shown in Fig. 4. In otherwords, it can be considered that the Nasu-Oroshi displays a property of a Bora.

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