フォッサマグナ西縁の糸魚川～静岡構造線(糸静線)に沿った長野県冨士見地域・山梨県白州地域の活断層の調査を行ない,新期断層変位地形を記載し,糸静線中部における第四紀後期の活動を考察した.その結果,富士見地:域(北部)と白州地域(南部)では,同じ糸静線活断層系に属しながら,断層変位様式がまったく異なることが明らかになった.
活断層は,西方の釜無山地・巨摩山地の走向と平行な北西～南東・北北西～南南東方向の走向を持つ.活断層は,位置・変位の方向・変位地形の形態的特徴から, Aタイプ:山麓線や糸静線に沿い西上りのもの,Bタイプ:逆向き(東上り)で断層線の形態が直線的なもの, Cタイプ:山麓線より数100m～数km東側に位置する西上りのもの,の3つに分類される. A・Cタイプは,地形面の擁曲や膨らみを伴うので逆断層,Bタイプは,変位地形が直線的に連続し,その横断面形が急傾斜なので,高角度の断層と考えられる.富士見地域には,A・Cタイプも分布するが, Bタイプが形成した逆向き断層崖と,その背後に続く小丘が顕著である.白州地域には, Bタイプはまったく分布せず,Aタイプが多い.
富士見地域北端の下蔦木において,1本の小河川が左横ずれするが,ほかでは河川の系統的屈曲のような左横ずれを示す地形は見られない.しかし,富士見地域には,Bタイプの断層と関連した杉の字雁行を示す小丘列が見られ,左横ずれを強く示唆する.富士見地域と白州地域北端の下蔦木の活断層は,中部日本の東西圧縮応力下で主圧縮軸と斜交する.このような条件のもとで,富士見地域の最北端ではA・Cタイプの断層が北に屈曲して収れんするため,A・Cタイプの断層での横ずれ変位が困難となる.その結果,地塊中,に歪が集中し,そこで左横ずれが発生し,Bタイプの断層によって形成された杉の字雁行の小丘列が現われる・J方,下蔦木より南方の白州地域の活断層は,東西方向の主圧縮応力軸とほぼ直交するため,Ru断応力が少なく,西上りの縦ずれ変位が顕著で,左横ずれは認められない.

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本研究では,仙台市における小売商業地の分布状況を1972年と1981年について比較し,その間に生じた変化を検討した.その結果は9次のとおりである.
1.特定の小売業の集積が極度に特化するという特異な業種構成を示す小売商業地は,両年ともにCBD内にのみ分布するが,その特徴を持つ地区数は7から9に増加し, CBD内のほぼすべてを占有するに至った.2.CBD以外で買回品(衣料品・文化品)小売業・歓楽関係業種が平均以上に集積する小売商業地は,198.年には仙台市から消失した.これは,買回品(衣料品・文化品)小売業・歓楽関係業種が市全域に広く散在するようになり,小売商業地間で業種構成に差がみられなくなる一方,CBDではこの種の小売業の集積が一層進み,その集積量に関してCBDとそれ以外の小売商業地との間で,格差が拡大したためと考えられる.

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River Maruyama and River Wada are located in southern part of Boso Peninsula, Along both rivers, One Pleistocene terrace and three Holocene terrace series can be observed. Upper Holocene terrace (Maruyama I terrace) is distributed widely from the upper to lower course. By field observations of terrace deposits, Maruyama I terrace is thought to be the fluvial fill-top terrace. Only in the lower course, drowned valley had been formed and marine silt and clay with shell fragements had been deposited from about 10, 000 y. B. P. till 0, 000y. B. P., But, before the emergence of Maruyama I terrace, this drowned valley had been filled by fluvial materials from both rivers.
Mid and Lower Holocene terraces (Maruyama IT and Maruyama III terraces) are distributed from the upper to lower courses. But distribution area of each terrace is smaller than that of Maruyama I terrace. From theupp er to middle course Maruyama II and III terraces are thought to be fluvial strath terraces because terrace deposits are composed of granule and sand whose thickness is less than 2m. But in the lower course those terrace are thought to be fluvial fill-top terrace because thickness of those terrace deposits is more than 5m.
Those evidences show that the terrace topography of this area had been formed by three cyclic changes of depositional and erosional processes of both rivers in the Holocene. And those changes were persumed to be caused by rapid sea level rise in early Holocene and seismo-tectonical movement during the Holocene.

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The purposes of this paper are to grasp the spatial structure of retail activities in the Tokyo commuting area and to consider its structure from a view point of activity space. In order to delimit the study area where commuting flows to the downtown Tokyo are dominant, principal component analysis was applied to commuting flow OD matrix of the Kanto Region.
By factor analysis on the geographical matrix of cities by workers of each retailing sectors, three factors were extracted and they were interpreted as “eating and drinking services, ” “shopping goods sales” and “convenience goods sales” (Table 1). Cluster analysis was adopted to find seven types of cities in retailing activities (Fig. 2). These seven types were regrouped to three major groups, namely, CBD location group, commercial center location group, and residential area location group. The commercial location group is developed along the commuter lines, especially in sub-centers and in suburban centers. The residential location group forms three concentric zones (Figs. 3 and 4).
The concept of “wedge shaped activity space” is based on consumer behavior and space cognition. It is useful to explain the spatial structure of retail activity in areas where coreoriented preference of inhabitants is quite notable. The metropolitan dominance in retailing and superiority of intervening opportunities on traffic link nodes were recognized.

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