東ポリネシアのラロトンガ島は南緯21度，西経160度に位置する．この島は周囲30kmで，前期更新世の玄武岩からなる開析されたカルデラと中央火口丘を中心に653ｍの最高峰を持つ山地が分布する．海岸沿いの低平地は平均幅400ｍほどのと700mほどの裾礁が縁どる．は更新世の離水扇状地・離水サンゴ礁と完新世の扇状地・砂堤列・湿地からなる．これまで，演者らは，こうしたを構成する地形について，地形と構成堆積物の観察，地形高度分布，C-14年代などの調査から，完新世海面変化，の離水過程が明らかにしてきた（Moriwaki et al., 2006; 森脇ほか，2009）．今回は，さらに追加したC-14年代資料や地形・堆積物の観察から，特に_丸1_の離水開始時期と_丸2_安定地域における完新世と更新世の地形形成の関係について報告する． 　の離水開始期：これまで，東岸においては詳しい年代測定がなされ，離水開始時期は約4,000 cal yr BPが得られている（Moriwaki et al., 2006）．今回，これに加えて，北岸の数地点において，最も内陸の浜堤堆積物のサンゴ礫のC-14年代測定を行った．もっとも古い年代は，北東岸において得られた 6,900 cal BPである．この年代は，旧ラグーンの海成堆積物の頂面6,300 cal yr BPとほぼ類似した年代となっている．北西岸では4,300 cal yr BPが得られ，東岸での離水年代と一致する．全体としては，ほぼ4000-5000年前ごろに海岸低地は離水を開始したものと推定される． 　完新世と更新世の地形の関係：サンゴ礁の礁原の幅は，南岸で広く，東岸から北岸で狭いので，サンゴ礁発達に違いがあるようにみえる．しかし，完新世のはサンゴ礁の礁原の発達度合いとは逆で，両者を合わせた幅は島全体を通じて1kmほどになり，ほぼ一定している．このことは，サンゴ礁は島全域にわたって類似した速さで発達し，完新世は完新世の礁原上において，東岸から北岸にかけてより広く発達したことを示唆する． 　東岸で砂堤列と堤間湿地が3列に分岐しているが，大部分は比較的広い1列の砂堤列と後背湿地が連続的に分布する．砂堤列は，標高の大きい北東岸では海抜6ｍに達する．他の海岸では海抜3－4ｍである．それらはサンゴ礫と砂から構成されている． 更新世の海岸地形は，最終間氷期の形成と考えられる離水した扇状地とサンゴ礁からなる．離水扇状地は山麓にほぼ連続的に分布する．完新世の扇状地より広く，連続性もよい．この海岸側にある更新世のサンゴ礁は露出が極めて限られる．現在は東岸と北岸の海岸と低地内に一部露出しているのみである．その高さは標高2ｍほどである．現在の海岸に露出する更新世サンゴ礁が内陸側では完新世の浜堤堆積物に覆われていくことや，完新世の砂堤堆積物が掘削された露頭観察によると，いくつかの場所では更新世のサンゴ石灰岩が現在の砂堤列堆積物の下に伏在していると考えられる．更新世の浜堤堆積物はみられない． 完新世の砂堤列地形は，一般には完新世のサンゴ礁の礁原上に形成されているとみられるが，更新世のサンゴ礁地形を核として形成されているところもある．完新世と更新世（最終間氷期）のとサンゴ礁は地形構成と配列が類似し，大局的には，類似した形成過程が同じ位置で生じ，現在の地形を形作っていると考えられる．

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宮城県の南部太平洋岸に発達する.宮城県の沖積層から, 軟体動物を主とする合計27種の海棲化石を採集し.それらの産状と現生生態に関する調査に基いて.化石群集の性格と当時の堆積環境とを考察した.

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By the C-14 method, a peat layer in the column of Loc. 2 is dated 15, 800±350 yrs. B. P. (GaK-3374). This is the first valid date about the Quaternary geology of Sendai Lowland and its vicinity.
This report is written to publish the date and to discuss on some relating informations. The subsurface geology and geomorphology of the area will be discussed in detail by Mr. Hiroaki Hase.

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中学・高校理科で津波の学習が行えるように，既存の組み立て式津波実験装置を改良した。この実験装置は海底面の隆起により津波を発生させるもので，とリアス式海岸の津波の比較，津波の波形の観察と波高の計測ができる。

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Quaternary deposits in the Atsumi region comprise six depositional sequences. Each sequence contains furthermore two facies associations relating to the glacio-eustatic sea-level changes. One is formed in barrier-island system during transgression and the other is in strand-plain system during regression.
The top of each sequence can be marked by the beach facies. The present altitude of the beach facies can be used as a marker of paleo-highstand sea-levels. Absolute crustal movement of the region has been inferred from the magnitude of the glacio-eustatic sea-level changes. The region had been subsided at the mean rate of 0.28m/ky.r. till 330Ka, and it abruptly turned to uplift at the mean rate of 0.17m/ky.r.
The level of each beach facies varies from place to place, probably reflecting differential crustal movements. Based on the difference in the elevation, wave length of the crustal bending is estimated to be 50 to 100km. Amplitude of the bending was less than 10m before 330Ka, while it was 50m after 330Ka.

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中国華北では水資源不足が問題となっており，それは食糧生産への負の制限要素となっている．これまで，千葉大学が地下水循環について研究を行ってきた中国華北平原において，統計資料から得た食糧生産量や社会経済指標の情報を用い，県スケールで，地形・地下水資源利用条件・社会経済要因や政策の影響を受ける人間活動・食糧生産量の相互作用を検討してきた．その中で，!)地形により地下水流動系の階層構造が形成され，おのおのの流動系の流出域に蒸発により高TDS区域が形成され，食糧生産性は制限される!)という地形・地下水流動系・TDS・食糧生産量の一連の関連が浮き彫りになってきた．今回は，コムギ・トウモロコシの生育時期のΣNDVI分布から，その複雑な空間分布と地形・地下水条件との関連性を再考察し，そして華北平原の地形により形成される地下水流動系階層構造を考察するため，華北平原の地理情報を用い地下水シミュレーションを行う．

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タイ国南部ナコンシタマラート

の砂州の形成と発達を，衛星画像，DEM，掘削調査，堆積物の年代測定結果などに基づいて明らかにした．砂州Iは長さ80 kmに及ぶ連続性の高い砂州で，砂州Iの背後にあたる砂州の西側には低湿地が広がり，泥炭層が形成されている．泥炭層基底付近の年代から砂州Iは7500年前頃形成されはじめたと考えられる．砂州Iの東側には砂州IIが発達し，最も新しい砂州IIIは現在の海岸線を縁取るように発達している．埋没砂州Yは南部のフラバット山付近から南に向けて延びており，の西縁付近には更新世に形成された砂州Xが顕著に発達している．これらのうち，砂州X，砂州I，砂州IIが北から南に向けて発達したと判断されるのに対し，砂州IIIは北のパクファナン入り江に向けて延びている．このような違いは1500年前頃以降の海況の変化を反映していると考えられる．

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In his previous papers, the writer has shown a peculiar contrast of the geoglogic structures of the lower Pliocene strata inn the Fossa Magna and in the outer zone of southwest Japan. And' he has concluded that. the structural lines of the.. lower Pliocene deposits do not conform with the general trend lines of the Honsyu arc or with the main structural lines of the outer zone of southwest Japan, but with the trend of the contour lines of the summit level in the outer zone of southwest Japan, and that the attitude of the lower Pliocene strata wasere made by the Pliocene crustal movements. From the above conclusions, . he has called in question that the crust deformation of the similar tendency as in the Pliocene crustal movements may have been continued during the later geologic period. In this paper he takes note of attitude of the. lower Pleistocene deposits and the inclinations of 4 coastal terraces arranged in step. on the southeastern coast of Kyûsyû. And he points out that the dips of strata and the inclinations of the terraces are the older, the steeper they incline towards E. or EES., and the crustal movements of the similar tendency have been continued or repeated in these districts since the early Pliocene age. And he inclines to conclude that the recent structural features of the lower Pliocene deposits in the outer zone of southwest Japan may represent the total result of the crust deformations accumulated slowly since the early Pliocene age.

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Pohang coastal plain, located along the Yeongil Bay, southeast coast of Korea Peninsula (Fig. 1), has marine and fluvial terraces, beach ridges, natural levee and back marsh. The writer tried to clarify the geomorphic development of this area.
Marine terraces along the coast of Yonghan-Ri are classified into three levels according to their altitude and continuity, namely surfaces I, II, and III in deceding order. These surfaces are originally abrasion benches cut into Tertiary bedrock, and covered with terrace veneers of gravel and sand bed of marine origin. Surface I is dissected by shallow channels and its surface soil is a little reddishly weathered. But surfaces II and III are scarcely dissected.
Fluvial terraces along the Neng-Cheon River are classified into three levels according to their relative height above river bed and continuity, namely surfaces I, II and III in desending order. Surfaces II and III are submerged by alluvium near the coast.
Two rows of beach ridges are recognized along the shore line. The outer one is continuous and relatively higher and the inner one is uncontinous.
Three groups of the natural levees are recognized along the Hyungsan River. The first group is scattered at the north side of river. The second group is well continued at the south side of river. The third one has been formed by the present course of Hyungsan River.
The writer measured radiocarbon dates of 7 samples from boring core and alluvium outcrops (Fig. 5), and analyzed grain side distribution of deposit from boring core No. 13 (Fig. 6). Based on the radiocarbon dates and grain size distribution, the writer drew the transition curve of sedimental environment in Pohang area (Fig. 7).
On the consideration of land classification and transition curve of sedimental environment, experienced the geomorphic development this coastal plain as follows:
1) The marine terrace surface I was formed at the high sea level during Last Interglacial. Surfaces II and III were formed at any stable period of lowering sea level to Würm or at the relatively high sea level in Würm Glacial.
2) The fluvial terrace surface I was formed at the same period of marine surface III formatioon. Surfaces II and III were formed at Würm maximun or at any stable period of rising sea level of Post Glacial.
3) Concerned with the Post Glacial word wide transgression, the sedimental environment in Pohang coastal plain changed as follow:
There was a stabe period about 10, 000 y. B. P. in rising sea lfvel of Post Glacial transgression, when the old valley of Neng-Cheon River was submerged and deposited by lower gravel bed (MG) shown at 20m below sea level in boring column.
The sea level about 6, 000 y. B. P. was fairly close to the present sea level, and since then it has been relatively stable with slight oscillation until the present, and natural levee and beach ridge have been formed during that time.

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Based on about 170 boring data, the author found the following points.
1) The base of the deposits underlying the coastal plain have valley forms under the Nanakita, the Umeda, the Hirose and the Natori Rivers. The depth of these valleys is -60m below the present sea level. The author assumes that these valleys were formed by fluvial erosion at the time of low sea level during the Würm ice age.
2) There are three flat surfaces ranging -10m to -20m, -30m to -40m and -50m to -60m respectively, below the present sea level. The first surface can be correlated with the Sendai Shitamachi river terrace (IV Surface). All the three surfaces are cut by the -60m valleys and their tributaries.
3) From such a form and the depositional features (Fig. 2), it is concluded that the gravel beds and other sediments were deposited after the maximum retreat of the Würm sea. This conclusion differs from the assumption of H. Okutsu (1964) who correlated the whole gravel beds underlying the coastal plain to the early Pleistocene Aobayama Formation which is distributed widely on the hilly part in Sendai.
4) It is presumed that the swelling of the flat surfaces have a causal relationship with the Nagamachi-Rifu tectonic line and that the movement along the tectonic line was not so influential on the formation of valleys during the Würm regression.

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