高知から室戸岬にかけての土佐湾北東部の海岸に沿って，標高数百m以下に海成段丘がよく発達している．特に室戸岬に近い半島南部では，段丘面の幅が広くなり，発達高度がより高いことから，切り立った海食崖と平坦な段丘面のコントラストが印象的であり，海成段丘地形の模式地として地理や地学の教科書等に頻繁に取り上げられてきた．本コースの見どころは，室戸沖で発生する地震性地殻変動と海成段丘形成史とのかかわりについて，これまでの研究成果をふまえて，傾動隆起などを実際に観察できることにある．さらに，ここ数千年間の地震隆起様式について，地形・地質学的証拠と測地・地球物理学的な見解に相違点があることを，現地を見ながら確認できる．

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The aims of the symposium “Termination of Last Glaciation and the Formation and Development of Jomon culture in Japan” are to clarify (1) what changes have occurred in natural environments in and around the Japanese Islands from the Last Glacial Maximum to the Postglacial periods, (2) what changes have occurred from Late Paleolithic culture to Jomon culture in terms of the relationship between natural and cultural environments, in paticular changes in coastal and land ecosystems and ways of human life, and (3) how and when the Jomon culture was established in terms of natural environmental changes.
The symposium consisted of three different parts: (1) Last Glacial Maximum (the age of upper Paleolithic culture, 20-15ka), (2) a transition period from Late Glacial to Postglacial (the age of formation of Jomon culture, 15-10ka), and (3) Postglacial period (the age of the development of Jomon culture, after 10ka). The topics were presented by three speakers for each part from the viewpoints of geology, paleoecology, pedology, and archeology.
The topics of presentations in the symposium are the following: Upper Paleolithic culture in Japan and East Asia (Masao Ambiru); Spatial distribution of the vegetation around the Last Glacial Maximum in Japan (Mutsuhiko Minaki); Paleoenvironmental changes of the Japan Sea since the Last Glacial period (Ryuji Tada); A land ecosystem in the transition to the Jomon age (Sei-ichiro Tsuji); The formation of Jomon culture in the Southern and Northern parts of Japanese Islands (Michio Okamura); Soil formation and the environmental change (Kan-ichi Sakagami); Development of Jomon villages (Yasuhiro Okada); Forest vegetation and utilization of wood during the Jomon period in Japan (Mitsuo Suzuki and Shuichi Noshiro), and Jomon agriculture: retrieval of evidence (Masakazu Yoshizaki). The discussions in the symposium have focused on the relationship between the changes in natural environments and ways of human life, in particular the change of land ecosystems and the utilization of natural resources.
The state of the art in studies of the natural environmental changes from the termination of the Last Glacial to the Postglacial and their relations to the regional development from the upper paleolithic culture to the Jomon culture in Japan are reviewed from various viewpoints, and future tasks of research are presented.

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Prominent emerged beachrock found at Shiomi, Tateyama City, Boso Peninsula is situated about 1m above present sea-level and its original extent is estimated 100m long and 20m wide.
Judging from the elevation, the beachrock is considered to have been formed during comparatively stable period between Genroku Earthquake (1703) and Taisho Earthquake (1923).
Discovery of this beachrock confirms the northern limit of its distribution in Japanese Islands.

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On several coastal terraces along the northeastern margin of Kitakami Massif, it is observed that a certain tephra deposit was transported on slope surfaces and then buried by the younger tephra. The lowermost horizon of the covering younger tephras is stratigraphically settled at the upper part of Takadate Volcanic Ash and Haehinohe Pumice.
Such disturbed layer showing active movement of materials on the former slope surfaces is not observed in other horizons of the tephra sequence in the area.
From this fact, it is surmised as follows : there existed some conditions that caused slope-instability concurrent with Upper Takadate Ash fall and preceding Haehinohe Pumice fall. Slopes were disturbed in different periods in accordance with their topographic sites.
Upper Takadate Ash, covering the deposits of the coastal terrace of about 10m a.s.l, partly includes angular boulders splitted from the stacks on former abrasion platform and is partly varied in mxied deposits of clayey ash and breccia. There is organic clay directly overlain with Haehinohe Pumice of which C-14 age was dated to 12700±270 yrs. B.P. This clay is abundant in pollens of Picea. These data may suggest the age and environment in the period of slope-instability.

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能登半島南西岸地域の隆起の原因を明らかにするため，沿岸の変動地形調査を実施した．本地域の海成段丘面は，高位のものからH1面～H4面，M1面・M2面，A面に区分できる．また，岩石海岸には離水ベンチが認められる．M1面はMIS 5eに形成された海成段丘面である．それより古いH1面～H4面には赤色風化殻が認められる．A面は，11世紀以前に離水した完新世段丘面（ベンチ）であると考えられる．これらの段丘面の高度には，累積的な南への傾動が認められる．調査地域北部では，富来川南岸断層が海成段丘面を変位させており，MIS 5e以降の累積鉛直変位量は約30 mである．その活動性はMIS 5e以降に高まったと考えられる．複数のベンチは間欠的な隆起を意味しており，調査地域の隆起運動は，南東～東傾斜の逆断層運動によってもたらされたと考えられる．このため，富来川南岸断層は沿岸から3～4 km沖合にある海底活断層に連続する可能性がある．

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御前崎周辺には,御前崎段丘(高度48～25m,三崎面相当の海成段丘)と4段の完新世海成段丘(高度15m以下)が分布する.御前崎段丘は,全体として西-南西に向かって傾動し,小規模な活断層,撓曲崖および背斜構造を伴う.御前崎段丘を開析する水系の分布形態および駿河湾側の海食崖上にみられる風隙の存在は,旧汀線が北西に位置することと不調和で,段丘形成後の変形を示している.御前崎段丘上にみられる東西方向に延びる低崖は,更新世段丘上に残された地震性隆起の記録である可能性がある.完新世海成段丘は4段に区分され,I面は後氷期海進最盛期直後,II面は約3,500cal BP以前,III面は2,150cal BP以前にそれぞれ離水したと考えられる.I面の内縁高度は14mに達するが,既存のボーリングコア解析から推定される海成層の上限高度は約3mにすぎない.これらの段丘の形成過程を,海溝型の活動間隔の短い地震による隆起と,地震間における沈降および活動間隔の長い地震による大きな隆起との和として解釈した.

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The Cordillera Blanca of the Peruvian Andes is a glaciated mountain range, the highest peak of which is Nevados Huascaran, 6768 meters high above sea level. The Cordillera Blanca is composed mainly of a batholith dating from 3 to 12 million years ago. The southwest slopes of the Cordillera are steep fault scarps developed in the Quaternary (WILSON et al., 1967 DALMAYRAC, 1974). These fault scarps are developed along what is here termed the Cordillera Blanca Fault. To the southwest, the Cordillera Blanca is bounded by the fault and the valley of Rio Santa, while to the northeast of the Cordillera, no notable active fault appears in the Mesozoic fold belt (Figs. 1 and 2).
The Cordillera Blanca Fault is easily recognized even on the LANDSAT images (Photo. 1). The total length of the fault is about 180-200 km and the relative height of fault scarps is over 4000 meters in muximum near Nevados Huascaran. The topographic features of the fault change from north to south. In the northern part, the fault scarp is high and steep and the fault line is simple. In the central part, the fault line waves and a cusp is formed to the northeast of Huaraz city. In the southern part, the relative heights of fault scarps become smaller and many fault scarplets run discontinuously in échelon (Figs. 3 and 5).
Two regions in the southern part of the Cordillera Blanca Fault were investigated in November, 1970. The amount of fault displacements at the Queroccocha Valley and the Tuco Valley were measured using correlative moraine ridges in the valley sides and surfaces of fluvial terraces in the valley floors (Figs. 5-12). Unfortunately, data on the absolute ages of these landforms was unobtainable. They were estimated by comparing the succession of moraines with the age-known moraines formed from the last glacial expansion to the present in the Chilean Andes (for example, MERCER, 1976).
Our investigation demonstrates that the Cordillera Blanca Fault is an active normal fault and that faulting has occurred progressively in the late Quaternary. The main results obtained follow :
1) Faulting has occurred progressively at least during the last 20, 000 years. The outermost morain ridge estimated about 20, 000 years ago (M₁) has a vertical offset of 57 meters at the Tuco Valley. The second ridge estimated about 13, 000 years ago (M₂) has a vertical offset of 25 meters at the Queroccocha Valley.
2) The average rate of vertical displacement along the fault is estimated to be 2 meters at the Queroccocha Valley and 3 meters at the Tuco Valley per one thousand years.
3) The values of vertical offsets which occurred during the different ages suggest that the amount of vertical displacements at one event of the faulting may be 2 and 3 meters at the Queroccocha and Tuco Valleys, respectively.
4) These results imply that the Cordillera Blanca Fault has a recurrence interval of about one thousand years.
5) If the faulting has continued at the same rate as in the late Quaternary, the amount of vertical displacement ranges from 2, 000 or 3, 000 meters for one million years. These values are of the same order as the relative heights of fault scarps at the western slope of the Cordillera Blanca. This means that the Cordillera Blanca Fault has been playing an important role in relief forming of the Cordillera Blanca and the Santa Valley.

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